wind loading - 966

59
IMPLEMENTATION OF EUROCODES WIND LOADING FOR SIGNS TO BS EN 12899 PHASE 2 REPORT Parsons Brinckerhoff Ltd. Queen Victoria House Redland Hill Bristol BS6 6US

Upload: st6812

Post on 07-Apr-2015

1.263 views

Category:

Documents


24 download

DESCRIPTION

WIND LOADING FOR SIGNS

TRANSCRIPT

IMPLEMENTATION OF EUROCODES

WIND LOADING FOR SIGNS TO BS EN 12899

PHASE 2 REPORT

Parsons Brinckerhoff Ltd. Queen Victoria House

Redland Hill Bristol

BS6 6US

DOCUMENT CONTROL SHEET

Title: Implementation of Eurocodes Wind Loading for Signs to BS EN 12899

Document No. Final Version

Originator: Client:

Parsons Brinkerhoff Ltd. Queen Victoria House Redland Hill Bristol BS6 6US

Highways Agency City Tower Piccadilly Plaza Manchester M! 4BE

AUTHORISATION

Prepared by:

Tony Harris Associate Signature Date

Checked by:

Kelly Croke Assistant Engineer Signature Date

Approved by:

Tony Harris Associate Signature Date

DISTRIBUTION AND REVISION STATUS

Date Description Issue

April ‘05 Draft for Comment A

April ‘05 Draft for Comment B

Sept ‘05 Final Version C

Copy No. Issued to:

1 Highways Agency Task Sponsor 1 1 1

2 PB Record Copy 1

Copy number: 1

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899

Wind Loading fir Signs to BS EN 12899

EXECUTIVE SUMMARY

Parsons Brinckerhoff, in association with their specialist sub-consultant Flint and Neill Partnership, were originally appointed by the Highways Agency to undertaken a review of BS EN 12899-1:2001 and provide UK specific advice on loadings to be used for the design of traffic signs in the UK. They were subsequently engaged to provide guidance on planted sign foundations and establish the scope of possible further guidance on the design of concrete foundations and also review the Phase 1 Report in the light of the production of a draft revised standard prEN 12899-1: 2005(E) and associated National Annex. The results of the main study are presented in the body of this report with proposals for the text of a future advice note presented in Annex A. Example design calculations have been prepared and are presented in Annex B. A series of trial calculations have been undertaken in order to assess the likely effect of the introduction of BS EN 12899 on the design of sign supports. The calculations do not cover the design of the signage itself or its attachment to the supports. A summary of the results of these calculations is presented in Annex C. The calculations show that wind loading governs the design of the sign supporting structures for all the configurations considered. Two loading classes are recommended for the design of signs in the UK, one applicable to England and Wales (WL7) and another to Northern Ireland and Scotland (WL9). WL7 results in design loads 7% less than that specified in the existing standard and WL9 leads to a 7% increase. The effects of the changes will therefore be regionally based with the majority of sign designs falling into the lower WL7 grouping, however the minor reduction in load effects is unlikely to have a net effect on the sizing of sign supports. It is therefore not anticipated that the net effect on the cost of the provision of signage within the UK will be significant. It is however clear that significant cost savings can be realised by designing signage supports for site-specific wind loads where signs are sited below the proposed limiting altitude. A supplementary report on foundations is included in Annex D. A summary of recommendations for the further development of the National Annex to prEN 12899-1: 2005(E) are presented in Annex E.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899

Wind Loading fir Signs to BS EN 12899

CONTENTS

1 INTRODUCTION ...............................................................................................................................1 2 REFERENCE DOCUMENTS ............................................................................................................1

2.1 Standards ..................................................................................................................................1 2.2 Information provided by the Highways Agency....................................................................2

3 TASKS...............................................................................................................................................2 3.1 Selection of Design Wind Pressures......................................................................................2 3.2 Identification of Exposed and Sheltered Areas.....................................................................6 3.3 Deflection Classes....................................................................................................................8 3.4 Advice on loading other than wind loading.........................................................................10 3.5 Example calculations .............................................................................................................12 3.6 Trial calculations ....................................................................................................................13 3.7 Foundation study....................................................................................................................15 3.8 Review of Draft National Annex ............................................................................................15

4 CONCLUSIONS ..............................................................................................................................18 APPENDIX I – LIMITING ALTITUDES AT STANDARD WIND LOAD CLASSES TO BS EN 12899-1 ANNEX A – RECOMMENDATIONS FOR TEXT FOR INCORPORATION INTO A TA ADVICE NOTE ANNEX B – EXAMPLE CALCULATIONS ANNEX C – SUMMARY OF TRIAL CALCULATIONS ANNEX D – SUPPLIMENTARY REPORT ON FOUNDATIONS ANNEX E – RECOMMENDATIONS FOR DRAFT NATIONAL ANNEX

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899

Wind Loading fir Signs to BS EN 12899

1 INTRODUCTION

Parsons Brinckerhoff (PB) and their specialist sub-consultant Flint & Neill Partnership (FNP) were appointed by the Highways Agency (HA) to provide advice on the loading of traffic signs designed in accordance with BS EN 12899-1:2001. Our Phase 1 Final Report summarised the tasks undertaken under the Phase 1 Study and provided text for incorporation into a TA advice note for the design of traffic signs within its Annex 1. In the interim, a revised version of BS EN 12899-1 was published (as prEN 12899-1: 2005(E)) and a draft National Annex for this standard was prepared. PB and FNP were subsequently re-appointed by the HA to review their earlier work against these new documents. This report incorporates the Phase 1 Final Report and amends it to reflect the results of the Phase 2 review. The key elements of the Phase 2 study were:

Review the Phase 1 Report considering the latest draft of BS EN 12899; additional wind load categories have been added and it may be possible to better reflect current designs carried out to BS 873;

Amend the requirements relating to loading/deflection to reflect the difference between standard and passively safe sign supports;

Review the structural requirements set out in the draft National Annex and provide advice/commentary.

2 REFERENCE DOCUMENTS

2.1 Standards

BS 449: Part 2: 1969: Specification for the use of structural steel in building. BS 873: Part 1: 1983: Road traffic signs and internally illuminated bollards. Methods of test. BS 873: Part 7: 1984: Road traffic signs and internally illuminated bollards. Specification for posts

and fittings. BS 6399: Part 2: 1997: Loading for buildings. Code of practice for wind loads. BS EN 40-7: 2002: Lighting columns. Requirements for fibre reinforced polymer composite

lighting columns. BS EN 1995-1.2: 2004: Design of timber structures. General – Common rules and rules for

buildings. BS EN 12899-1: 2001: Fixed, vertical road traffic signs. Part 1: Fixed signs (incorporating

corrigendum No.1) CP 118: 1969: The structural use of aluminium. BS EN 12767: 2000: Passive safety of support structures for road equipment – requirements and

test methods. prEN 12899-1: 2005(E): Fixed vertical road traffic signs. Part 1: Fixed signs. CP3: Chapter V: Part 2: 1972: Basic data for the design of buildings. Wind loads ENV 1991-2-4: Eurocode 1: Basis of design and actions on structures. Wind actions. prEN 1991-1-4: Eurocode 1: Actions of structures – General actions – Part 1.4: Wind Actions,

dated 2004-01 (to be known as BS EN 1991-1-4). TA 89/04 – Use of passively safe signposts to BS EN 12767. UK National Annex to BS EN 1991-1-4, Draft 4.5, August 2004

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 1

Wind Loading fir Signs to BS EN 12899

2.2 Information provided by the Highways Agency

Traffic sign example dimensions (sign sizes 01.xls) prEN 12899-1: 2005: National Foreword and National Annex (undated)

3 TASKS

3.1 Selection of Design Wind Pressures

Advice was required on the selection of a wind load class, in accordance with BS EN 12899-1 using the provisions of BS EN 1991-1-4, the Eurocode on wind actions, covering the majority of the UK that could be applied to the design of traffic signs. BS EN 12899-1: 2001 contained seven wind load classes whilst prEN 12899-1; 2005(E) contains nine wind load classes. These are reproduced in Table 1.

BS EN 12899-1: 2001 prEN 12899-1: 2005(E)

Class Wind Loads1 (kN/m2) Class Wind Pressure (kN/m2)

WL0 No performance determined WL0 No performance

determined

WL1 0.40 WL1 0.40

WL2 0.60 WL2 0.60

WL3 0.80 WL3 0.80

WL4 1.00 WL4 0.90

WL5 1.20 WL5 1.00

WL6 1.40 WL6 1.20

WL7 1.60 WL7 1.40

WL8 1.50

WL9 1.60

Table 1

National climatic information for use with BS EN 1991-1-4 must be obtained from the appropriate National Annex. Work proceeded using the draft listed in Section 2.1. At the time of preparation of this report BS EN 1991-1-4 had been published but the UK National Annex to this standard was still being prepared by the BSI B/525/1 Working Group 2 committee. Work proceeded using the draft listed in Section 2.1; it is understood that a draft for public comment will be issued early in 2006. The UK National Annex to BS EN 1991-1-4 requires determination of the following parameters in order to calculate a site wind speed. 1 Note that BS EN 12899-1:2001 incorrectly labelled ‘wind pressure’ as ‘wind load’. This has been corrected in prEN 12899-1: 2005(E).

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 2

Wind Loading fir Signs to BS EN 12899

(i) Wind direction (to apply a direction factor to produce a site wind speed with equal risk of

being exceeded from any direction); (ii) Distance from the site to the sea in the wind direction (to account for the effect of ‘country’

terrain on the mean wind and turbulence in the atmospheric boundary layer); (iii) Distance from the site to the edge of town, for sites in ‘town’ terrain (to account for the effect

of rough terrain immediately upwind of the site on the mean wind and turbulence in the atmospheric boundary layer);

(iv) Site altitude (to account for increases in wind speed due to large scale gentle topographic features); and

(v) Site topography (to account for acceleration of flow by local significant topographic features). In order to derive a wind pressure applicable to the design of road signs for the majority of the UK, it is necessary to make a number of simplifying assumptions. These assumptions will ensure a conservative result provided the design wind pressure is applied correctly to appropriate sites. The assumptions adopted may be summarised as follows: Information provided by the HA indicates that traffic signs in current use are no higher than 9 metres. Hence, the design wind pressure shall be calculated at 9 metres above ground level. It follows that this approach is conservative for signs where the centre of wind loading is less than 9 metres above ground level. The wind direction shall always be taken as 240º ETN as this is the prevailing wind direction in the UK and the corresponding wind direction factor of 1.0 applies. Note that the direction factor for other wind directions is always less than 1.0. When wind passes from the sea over land, the rougher terrain modifies the variation of wind speed and wind turbulence with height. In general terms, the wind speed reduces and the turbulence increases; the net effect of these two contradictory factors is to reduce the dynamic wind pressure. With increasing distance from the coast, the effect of the surface roughness of the sea diminishes until the wind speed and turbulence profiles are in equilibrium with the country terrain. Changes to the wind speed and turbulence profiles start at ground level and grow upwards through the atmospheric boundary layer. Thus, for short structures, the wind appears to be in equilibrium with country terrain within several kilometres of the sea. The UK National Annex to BS EN 1991-1-4 already simplifies the treatment of the roughness of the ground surface by only including a ‘country’ and ‘town’ category. In nature, there is greater variation, for example, from mudflats, to farmland, to woodland, to domestic housing, to cities. Also, the UK National Annex only includes the transition from ‘sea’ to ‘country’ (to ‘town’). In practice, other sequences will occur although they are unlikely to result in higher design wind pressures. The transition from ‘country’ to ‘town’ terrain has the same effect as the transition from ‘sea’ to ‘country’ terrain; wind speeds reduce and turbulence increases with the net effect of a reduction in the dynamic wind pressure. Hence, the effect of town terrain shall not be included in the calculation of a wind pressure applicable to the majority of the UK. The UK National Annex includes a wind speed map for the UK, corrected to mean sea level. An altitude factor is then applied to the wind speed for a particular site and is given by the expression (1 + 0.001∆) where ∆ is the site altitude (in meters). To enable the derivation of a wind pressure applicable to the majority of the UK, a limiting altitude shall be set which incorporates the majority of conurbations and A-class roads and above (the majority of expected traffic sign sites). The design wind pressure shall be applicable below this limiting altitude. It should be noted that specifiers and designers of traffic signs will need to know the altitude of the proposed site. This information is readily available; for example the

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 3

Wind Loading fir Signs to BS EN 12899

Ordnance Survey’s “Get a Map” service (www.ordnancesurvey.co.uk/oswebsite/getamap) will provide a map of a 4km square with altitude contours at a scale of 1:50,000 centred on a place name, postcode or grid reference. A review was undertaken for each county, council and unitary authority in the UK. The greatest basic wind speed at mean sea level within each county / council /unitary authority was identified from the wind speed map in the UK National Annex. A limiting altitude was set to include the majority of expected traffic sign sites across the UK; the peak velocity pressure at the limiting altitude was then calculated for each county / council /unitary authority. The different classes of wind pressure given in Table 1 above are equivalent to the peak velocity pressure given in equation NA3 of the UK National Annex. Peak wind load has units of force and is obtained by multiplying the peak velocity pressure by the projected area, the appropriate drag factor and the appropriate partial safety factor on wind load. As a result of the above review, it was concluded that use of a single wind load class for the whole of the UK would be unduly conservative. Thus, it was decided to recommend different wind load classes for England, Northern Ireland, Scotland and Wales. As the underlying wind loading provisions in BS EN 1991-1-4 and the draft UK National Annex have not changed since the issue of the Phase 1 Final Report, it is considered that the peak velocity pressures previously calculated should still apply. However, it can be seen from Table 1 that the names of the classes need to be amended. This is summarised in Table 2.

Wind Load Class Country BS EN 12899-1:

2001 prEN 12899-1:

2005(E)

Peak velocity pressure (kN/m2)

Limiting altitude

(m)

England WL6 WL7 1.40 250

Northern Ireland WL7 WL9 1.60 250

Scotland WL7 WL9 1.60 250

Wales WL6 WL7 1.40 250

Table 2

It should be noted that these pressures do not apply to exposed areas or sites with significant local topography; these cases are discussed in Section 3.2. Other limitations must also be applied to account for regions of the UK with high wind speeds and high altitudes. In England, the Isle of Man should be wind load class WL8 with a limiting altitude of 250m. In Scotland, the peak velocity pressure at the limiting altitude of 250m exceeded 1.60kPa (for WL9, the highest class in BS EN 12899-1) in the following Councils:

Western Isles Highland Argyll & Bute Orkney

Shetland Moray Perth & Kinross

In these Councils, a wind pressure of 1.60kPa corresponded to a much lower site altitude than 250m and is lower than a significant number of expected traffic sign sites. Thus, in these Councils, it is suggested that wind loads are calculated by direct application of BS EN 1991-1-4 and the UK National Annex.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 4

Wind Loading fir Signs to BS EN 12899

Comparison between the wind speed maps in BS6399: Part 2 (the current lead UK wind loading code) and the UK National Annex shows that design wind speeds in Scotland have increased, with the greatest increases in the north. The wind speed map in the UK National Annex may be considered as statistically more reliable, as it has been derived from 30 years of wind speed measurements, whilst the map in BS6399: Part 2 was derived from only 11 years of data. It is important to understand the conservatism introduced to the design process by the adoption of a single wind load class for each country within the UK. This is illustrated by the histogram for England in Figure 1 below.

EnglandHistogram of peak velocity pressures at a limiting altitude of 250m or below

0

2

4

6

8

10

12

14

16

18

20

600

700

800

900

1000

1100

1200

1300

1400

1500

Peak velocity pressure (kPa)

Num

ber o

f Cou

ntie

s/Un

itary

Aut

horit

ies

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

FrequencyCumulative %

Figure 1

It can be seen that one location (the Isle of Man) falls above the wind pressure of 1.4kPa corresponding to wind load class WL7 – this is dealt with as a special case. One county (Cornwall) has a wind pressure of 1.4kPa at the limiting altitude of 250m. All the remaining counties or unitary authorities have “wind loads” of less than 1.4kPa at the limiting altitude of 250m or below. Some designers may wish to take advantage of this conservatism. Thus separate tables have been prepared, giving the limiting altitude at which the wind pressure is 1.4kPa for England and Wales and 1.6kPa for Northern Ireland and Scotland. These are presented in Appendix I; it should be noted that they have been rounded down to the nearest 10 metres. For example, a designer of a traffic sign for a site in Hampshire with an altitude of 100m could simply decide to select a standard sign designed for a wind pressure of 1.4kPa as the site is below the general limiting altitude of 250m for England. Alternatively he could look at the data in Appendix I. This shows that the limiting altitude corresponding to a wind pressure of 1.4kPa in Hampshire is 400m. This is comfortably in excess of the limiting altitude of 250m set for England. Thus, it may be worthwhile

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 5

Wind Loading fir Signs to BS EN 12899

calculating the wind pressure at the site using BS EN 1991-1-4 and the UK National Annex. This would give a wind pressure significantly lower than 1.4kPa which, when considered with other design criteria (e.g. deflection), may result in a more economic design. As a second example, a designer of a traffic sign for a site in Cheshire with an altitude of 300m would look at the data in Appendix I. This shows that the limiting altitude corresponding to a wind pressure of 1.4kPa in Cheshire is 340m. The site altitude falls between the general limiting altitude of 250m applicable to the whole of England and the specific limiting altitude for Cheshire of 340m. Thus, the designer knows that a sign designed for the standard wind pressure of 1.4kPa would be safe. As a third example, a designer of a traffic sign for a site in Neath Port Talbot with an altitude of 330m would look at the data in Appendix I. This shows that the limiting altitude corresponding to a wind pressure of 1.4kPa in Neath Port Talbot is only 280m. Thus, the designer would have to calculate a higher wind pressure at the site using BS EN 1991-1-4 and the UK National Annex.

3.2 Identification of Exposed and Sheltered Areas

Advice was required on the identification of both exposed areas (including other locations) where full wind calculations are required for safety, and sheltered areas where significant economies may be made by calculation to BS EN 1991-1-4. It should be noted that exposed sites have been defined in HA Departmental Standard BD26/04 (for the design of lighting columns) as follows:

Sites at high altitude, above 250m; Sites closer than 5km from the coast; and Sites subject to significant local funnelling.

The first two of these categories shall not be adopted for traffic signs. The matter of site altitude has already been discussed in section 3.1 of this report and is addressed in the recommendations for design wind pressure given in section A1 of Appendix A. Proximity to the coast is of concern in the design of lighting columns as they are predominantly of circular cross-section. Under smooth, laminar flow conditions they can be prone to aerodynamic instabilities giving rise to significant dynamic response. This is not considered a significant issue for traffic signs where the predominant area presented to the wind is a flat plate. Sites subject to significant local funnelling remain relevant to the design of traffic signs. As an example, funnelling can occur in valleys where the windward end is wider than the rest of the valley. Wind along the axis of the valley will be accelerated by the reduction in volume as the valley narrows; if the valley is of constant width, then the flow will not be accelerated. In valleys where local funnelling of the wind occurs, the design wind pressure shall be multiplied by a funnelling factor that shall not be less than 1.2. It should be noted that high motorway embankments might form a similar topographic feature, resulting in funnelling. A further category of exposed site needs to be included. This covers sites where local topography accelerates the flow (note that the altitude factor discussed in Section 3.1 only allows for gradual large scale changes in altitude). This category is also required for lighting columns and is included in BS EN 40-3-1: Annex B (to which BD26/04 refers). For consistency with the other recommendations in this report, it is considered that the provisions for topography given in BS EN 1991-1-4 should be adopted, rather than those in BS EN 40-3-1. It should also be noted that topography is called “orography” in BS EN 1991-1-4. The UK National Annex to BS EN 1991-1-4 states that the procedure given in the Eurocode should be used for sites that lie within the shaded zones shown in Figure NA2. Outside these zones, the effect of

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 6

Wind Loading fir Signs to BS EN 12899

topography (or “orography”) need not be considered. Figure NA2 is reproduced in Figure 2 for information:

Figure 2

It can be seen from this figure that topography (or “orography”) is only considered significant where the upwind slope is greater than 0.05 (this is approximately equal to 3º). Increases in wind speed resulting from a change in altitude due to shallower slopes are covered by the altitude factor (refer to section 3.1). Advice was also required for sites where full calculation of wind loading to BS EN 1991-1-4 may give significant economy. It is considered that the greatest economy may be obtained where:

The specific limiting altitude for a particular county, council or unitary authority is significantly greater than the general limiting altitude of 250m;

The specific site altitude is significantly lower than the general limiting altitude of 250m; or The distance to the centre of pressure of a sign is significantly less than the value of 9 metres

used in the derivation of standard design pressures. These matters have already been addressed in Section 3.1 and Section A1 of this report. Reduced wind pressures may also be calculated for sites in “town” terrain (note that the standard design pressures were derived in “country” terrain). The rougher ’town‘ terrain has the effect of reducing wind speeds and increasing turbulence with the net effect of reducing dynamic wind pressures. In “town” terrain, the effective aerodynamic ground plane will be displaced upwards by closely packed buildings. The aerodynamic ground plane is the height above ground level at which the atmospheric boundary layer starts. Wind pressures calculated by BS EN 1991-1-4 apply above this height. The region between the aerodynamic ground plane and ground level is called the interfacial layer. The wind still flows within this region, but in many directions so that the total net flow is zero. Local flows in the interfacial layer will be channelled and funnelled by the layout of the buildings. This is a complex situation and no specific guidance can be given to provide economy in design (however, it is considered that the “country” terrain standard design pressures provide a safe basis for design within this region). BS EN 1991-1-4 provides design wind speeds within the interfacial layer in “town” terrain by assuming a constant value from 10 metres above the aerodynamic ground plane down to ground level.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 7

Wind Loading fir Signs to BS EN 12899

The height of the aerodynamic ground plane is typically 80% of the average height of the buildings and thus it can be seen that the majority of traffic signs will fall within the interfacial layer. The effect is illustrated in Figure 3:

Wind direction

ABL wind profile

Aerodynamic ground plane Local flow

between buildings

GL

Figure 3

3.3 Deflection Classes

Advice was required on the selection of suitable deflection classes in BS EN 12899-1 for application in the UK. Additional advice was sought on appropriate requirements for more flexible passively safe signposts in aluminium or fibre reinforced plastic. Historically, BS 873: Part 7 required that, for steel and aluminium posts, “The horizontal deflection measured at the centre of the sign shall not exceed 1/40th of the distance from the centre of the sign to the ground when either the face or the rear of the sign assembly is subjected to a uniform pressure of 1kPa ± 2.5%”. It should be noted that a slope of 1/40th is equivalent to a deflection of 25mm/m. Furthermore, it follows that this is a hypothetic deflection as it is linear (it is simply the slope between the base and the point under consideration); in reality deflected shapes will be curved. It is understood from the HA that there have been no reported problems with the application of existing requirements for the horizontal deflection of traffic signs and they have resulted in satisfactory performance. Thus, the intention is to select a deflection class from BS EN 12899-1 that gives a similar level of performance. As set out in section 3.1, it is proposed that the majority of regions in England and Wales will use wind load class WL7 with a wind pressure of 1.4kPa. Similarly, Scotland and Northern Ireland will use wind load class WL9 with a wind pressure of 1.6kPa. Furthermore, prEN 12899-1: 2005(E), clause 5.4. specifies that “The wind load for calculating the temporary deflection shall be based on the wind loads multiplied by 0.56, and no partial action and material factors are applied…”, reflecting the fact that temporary deflections are based on a one year return period load event. Thus, the wind load for calculating temporary deflections in England and Wales becomes 0.784kPa (= 1.4 x 0.56). Similarly, in Scotland and Northern Ireland the value becomes 0.9kPa (= 1.6 x 0.56).

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 8

Wind Loading fir Signs to BS EN 12899

As the “wind loads” for calculating deflections to BS EN 12899-1 are lower than those historically used in the UK, then the deflection limits should be reduced pro-rata. Thus, in England and Wales, the deflection limit for bending should be 20mm/m and in Scotland and Northern Ireland should be 22.5mm/m. prEN 12899-1: 2005(E) contains seven maximum temporary deflection classes for bending and torsion; they are reproduced in Table 3 below:

Class Maximum temporary deflection – bending

(mm.m-1) Class

Maximum temporary deflection – torsion

(degree.m-1)

TDB0 No performance determined TDT0 No performance

determined

TDB1 2 TDT1 0.02

TDB2 5 TDT2 0.06

TDB3 10 TDT3 0.11

TDB4 25 TDT4 0.29

TDB5 50 TDT5 0.57

TDB6 100 TDT6 1.15

Table 3

It can be seen that the closest class is TDB4 with a limit of 25mm/m. If this class were adopted, it would represent a relaxation of current requirements of 25% for England and Wales and 11% for Scotland and Northern Ireland. The HA has already set deflection requirements for passively safe signs meeting the requirements of BS EN 12767; these are currently defined in Departmental Standard TA 89/04 as 1/25th of the overall sign height for a uniform wind pressure of 1 kPa. This is equivalent to a deflection of 40mm/m. However, this limit needs to be adjusted for the reduced wind pressure to prEN 12899-1: 2005(E) for calculating temporary deflections, giving a limit of 31.5mm/m for England and Wales and 36mm/m for Scotland and Northern Ireland. Again it can be seen that the closest class is TDB5 with a limit of 50mm/m. This would represent a relaxation of current requirements of 59% in England and Wales and 39% for Scotland and Northern Ireland. Thus, to achieve the same requirements as currently used, the parameters given in Table 4 should be adopted:

Sign Class Uniform wind pressure Deflection Class

Not passively safe 1 kPa TDB4

Passively safe 0.625 kPa TDB4

Table 4

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 9

Wind Loading fir Signs to BS EN 12899

However, this approach is not in accordance with the provisions of prEN 12899-1: 2005(E); the wind load for calculating temporary deflections should be taken as 0.56 times the un-factored design wind load. Thus, compliance with prEN 12899-1: 2005(E) will result in a relaxation of deflection limits currently used in the UK, as discussed above. Text recommended in Annex A for inclusion in a TA Note complies with the provisions of prEN12899-1 and gives different deflection classes for passively safe and non passively safe posts; this will result in a relaxation of deflection limits. No guidance is given in BS 873 for limits on torsion. However, it is considered that deflection of a point on a structure should take account of all strains induced. It may be accepted for a traffic sign that axial and shear deformations are insignificant, but deflections due to bending and torsion should be taken into account. Thus, for compatibility, class TDT4 shall also be specified. It should be noted that the wind pressure for calculating deflections is the same across the UK. It follows that the deflection limits will be exceeded more frequently in areas with higher basic design wind speeds. This is not considered an issue as motorists are expected to use the same threshold to decide whether they will make their journey. In windier parts of the UK, the decision not to travel will be made more often. The equivalences noted above assume that the same force co-efficients (Cf) are used for traffic signs designed to BS 873-7 and BS EN 12899-1. BS 873-7 does not specify force coefficients nor does it give references for selecting suitable design values. However, the wind loading standard at the time of publication of BS873-7 was CP3: Chapter V: Part 2. This standard does not give specific guidance for sign boards, but, it is reasonable to assume that a value of Cf = 2 would have been adopted for a flat rectangular plate perpendicular to the wind. CP3 also gave reduction factors for members of finite length; a flat plate with an aspect ratio of 3 would have a reduction factor of 0.63, giving a net drag factor of 1.27. Conversely, specific guidance is given on force co-efficients for flat rectangular signboards in EN 1991-1-4. For the ground clearances and sign sizes provided by the Highways Agency, it follows that a value of Cf = 1.8 would apply. This value is based on specific wind tunnel tests in turbulent flow of scale models of signboards undertaken by BRE and Oxford University 2. It should be noted that different force co-efficients would apply to other sign shapes, such a triangles or circles.

3.4 Advice on loading other than wind loading

Advice was required on the selection of suitable classes in BS EN 12899-1 for loads other than wind loads. These included dead loads, point loads and dynamic loads from snow clearance.

3.4.1 Dead Load

No classes are specified for dead loads in prEN 12899-1: 2005(E). Instead, it is stated that “Dead loads are the weight of the individual components of the finished sigh such as substrate, sign housing, protective edge, stiffeners, luminaires, supports, fixings etc..”. It is considered that these words are adequate and no additional advice is necessary.

2 Refer to The designer’s guide to wind loading of structures. Part 2 – static structures. N.J. Cook

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 10

Wind Loading fir Signs to BS EN 12899

3.4.2 Point Loads

Six classes of point load are given in prEN 12899-1: 2005(E); they are reproduced in Table 5 below:

Class Point Load (kN)

PL0 No performance determined

PL1 0.15

PL2 0.30

PL3 0.50

PL4 0.75

PL5 1.00

Table 5

It is considered that the purpose of the point load is to ensure that the fixing of the sign to the post is adequate to prevent twisting about any axis of rotation. This is implied by the position of the loads indicated in the illustrations in BS EN 12899-1: Annex C. BS 873 does not include a theoretical point load to be included in the design calculation process. However, BS 873-1 includes a physical load test to determine resistance to twisting. This involves application of “a force of 625N at a rate of 6 N/s to 8 N/s at the extremity of the sign or luminaire so as to provide maximum torque about any possible axis of rotation”. It can be seen that the test load of 625N falls exactly midway between point load classes PL3 and PL4. However, the point loads given in BS EN 12899-1 are for inclusion in a theoretical calculation to determine whether a twisting moment exceeds a design twisting resistance (i.e. a characteristic twisting resistance divided by a partial safety factor). Thus comparable performance between BS EN 12899-1 and BS 873 is more likely to be achieved by specifying load class PL3. It should be noted that the copy of prEN 12899-1: 2005(E) provided for this work did not include figures in Annex A. As some of these figures describe the positioning of point loads, it is proposed that the advice given above is reviewed once a full copy of the standard can be made available.

3.4.3 Dynamic Loads from Snow Clearance

Five classes of dynamic snow loads are given in prEN 12899-1: 2005(E);; they are reproduced in Table 6 below:

Class Dynamic Snow Loads (kN/m2)

DSL0 No performance determined

DSL1 1.5

DSL2 2.5

DSL3 3.0

DSL4 4.0

Table 6

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 11

Wind Loading fir Signs to BS EN 12899

Guidance on sign areas for load application is given in BS EN 12899-1: Annex A2. It should be noted that the copy of prEN 12899-1 provided for this work did not include figures in Annex A. As some of these figures describe the positioning of dynamic snow loads, it is proposed that the advice given above is reviewed once a full copy of the standard can be made available. This load represents the effect of snow being thrown sideways by clearance vehicles. Guidance on selection of appropriate levels of load has been obtained from the Finnish Road Administration (FINRA). This is summarised in the Figure 4, which gives the magnitude of the dynamic load from snow clearance (p) as a function of clearance vehicle speed and distance of the sign from the edge of the carriageway (e).

Figure 4

It should be noted that the magnitude of the load is not a function of the depth of snow being cleared. In the UK, traffic signs are commonly placed closer than 3.5 metres from the edge of the carriageway. Thus, it can be seen that the appropriate load class is DSL4 where the clearance speed is 60 km/h (37.3 mph) or more and DSL2 where the clearance speed is less than 60km/h. For application within the UK, it is suggested that the separator between the two classes is set at 40mph as this corresponds with a commonly used speed limit and will be easier to implement. The decision to design for dynamic snow clearance loads may rest with the Overseeing Organisation. However, where consideration of this load case is necessary, it is considered that the classes recommended above are adopted.

3.5 Example calculations

3.5.1 Approach

Example calculations have been undertaken to illustrate the typical design processes associated with the application of BS 12899, which also include an illustration of the data required to undertake the detailed derivation of the site-specific wind load in accordance with BS EN 1991-1-4. The calculations illustrate the structural design of the supporting post and consider the following:

Sign and post size definition; Partial factors;

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 12

Wind Loading fir Signs to BS EN 12899

Material and section properties; Derivation of wind loading (including consideration of eccentricity); Post design (based on wind load); Deflection check; Snow loading check; Point load check; and Illustration of derivation of wind loading to BS EN 1991-1-4.

3.5.2 Commentary

BS 873 contained very little by way of design requirements or guidance. The amount of calculation required when applying BS EN 12899 is therefore significantly greater. Having said this, the adoption of standard loading classes eliminates the most involved and specialised area of the design, i.e. the derivation of site-specific wind loads. The remaining calculations are relatively straightforward and lend themselves to simple programming by spreadsheet. From this point of view, once a designer has appreciated the processes involved, the applications of the requirements of the standard are relatively straightforward. The derivation of site-specific wind loading using BS EN 1994-1-1 is considerably more involved than the application of standard loading classes and our calculations show that significant economies can be derived. However, it is not anticipated that signage designers will be familiar with or confident in the use of this standard and will only therefore resort to this in occasional, exceptional cases. It should be highlighted that, in such cases, expert advice be sought.

3.6 Trial calculations

3.6.1 Approach

A series of trial calculations were undertaken following the same methodology set out in the example calculations described in section 3.5. A range of sign sizes was selected from the matrix of example sign dimensions provided by the HA which covered what was considered to be the spectrum of typical sign sizes encountered on UK trunk roads. To allow comparisons to be made to existing practice, example designs were prepared to both BS EN 12899 and its predecessor BS 873. A summary of the results of the calculations undertaken can be found in Table B1 of Annex B. In addition to this a series of standard designs currently in use in HA Area 2 were obtained and comparative designs were undertaken, again to both BS 873 and BS EN 12899. A summary of the results of these calculations undertaken can be found in Table B2 of Annex B. However, a particular concern was raised because BS 873 made no mention of the use of a pressure coefficient, there was a risk that some designers might have interpreted that to mean that the sign loading should be based simply on the prescribed wind pressure of 1.5kN/m2. To investigate the potential consequences of this, parallel designs were prepared to that standard, both with and without the application of the pressure coefficient. Designs were undertaken to BS EN 12899 based on the proposals for both WL7 (England and Wales) and WL9 (Northern Ireland & Scotland) wind loads. Design calculations also considered eccentricity of wind loading, deflection criteria, snow and point load requirements. As outlined in 3.1 above, where signs are to be sited at levels significantly below the limiting altitude or where sign heights are significantly less than 9m, there is the potential benefit in undertaking the calculations necessary to derive a site-specific wind load in order to take advantage of the economies that can be achieved by considering a reduction in wind loads. Our calculations have therefore included the

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 13

Wind Loading fir Signs to BS EN 12899

derivation of wind loads using BS EN 1991-1-4 for a similar site location to that used in the example in BS EN 12899, based on an altitude of 50m. The HA Area 1 standard designs were based on the use of steel sections with a yield stress of 275MPa. This grade was therefore adopted throughout the calculations. For any given sign size, a series of designs were undertaken using a variety of post diameters and wall thicknesses in order to minimise the final weight of steel used for the posts. While this was a convenient measure of design optimisation for this study, it is recognised that in practice, a limited range of the more popular section sizes are likely to provide the most economic solutions.

3.6.2 Commentary

In the following comparisons drawn using Table C1, which compares designs undertaken using both BS 873 and BS EN 12899, the base calculations against which comparisons are made (Case 2) assumes that a pressure coefficient (Cf) has been applied, as required by the previous wind loading standard BS 6399. The wind loads derived by ignoring Cf (Case 1) were 44% lower. It can be seen that the WL7 loading class (Case 3) resulted in wind loads 7% lower than those derived using the base case whereas those in the WL9 class (Case 4) result loads 7% higher. Use of class WL8 for the whole of the UK was not deemed appropriate and so a direct match would clearly not be achieved (refer to Section 3.1 above for a more detailed discussion). In terms of material utilizations however, the WL7 class posts were identical to the base case and the WL9 post material usage increased by between zero and 24%. The primary reason for this disparity was the step-change caused by selecting the number, diameter and thickness of posts. Therefore, if existing designs are undertaken by correctly applying Cf, there should not be significant effects on design economics. Case 5 clearly illustrates the scales of economy that can be achieved by using a site-specific wind load. Table C2 compares designs undertaken to BS 873 (Cases 1 & 2) and BS EN 12899 (Cases 3, 4 & 5) to standard solutions used for signage installed within HA Area 1 (Case 0). It can be seen that there is generally agreement between the Case 2 and Area 1 results, which suggests that, in this case, at least Cf has been taken into account. The other cases show a similar relationship to that already noted in Table C1 but with some minor discrepancies. These small differences are likely to be a result of a combination of a slight difference between the Cf value used in the Area 1 and PB calculations and the step change resulting from increasing the posts by a serial size to cater for a small increase in load effect.

3.6.3 Implications for Design Input

Indicative figures for the relative level of input required to undertake the design of signage supports are given in Table 7 for the following cases:

Case 1 - using BS873 criteria Case 2 - using EN12899 standard loading classes Case 3 - using EN12899 with site specific wind loads derived using BS EN 1991-1-4.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 14

Wind Loading fir Signs to BS EN 12899

BS 873 EN 12899

Using Wind Load Classes

EN 12899 Calculating wind load

for specific site

Time Required 15 - 20 min 40-45 min 1.5 -2 hours

Checks Undertaken • Bending Moment• Shear • Deflection

• Moment • Shear • Deflection • Torsion

• Moment • Shear • Deflection • Torsion

Loads Applied • Wind UDL • Wind UDL • Snow • Point Load

• Wind UDL • Snow • Point Load

Table 7

The times noted above are typical of those required for a reasonably experienced graduate engineer to undertake the necessary design calculations by hand. The modest increase between cases 1 and 2 reflects the increased number of basic checks required by EN 12899. It is likely that in practice, designers will automate the calculation process by developing spreadsheet based solutions and in that instance, it seems likely that the additional effort associated with the use of EN12899 will be minimal. The calculation of site specific wind loads will result in significant additional design effort. While the process can be assisted by the use of bespoke spreadsheet based tools, their development would involve quite significant effort and the application and interpretation of EN 1991-1-4 will require a higher level of skills than the basic calculations involved in cases 1 and 2.

3.7 Foundation study

Refer to Annex D.

3.8 Review of Draft National Annex

3.8.1 Introduction

The structural requirements of the UK National Annex to prEN 12899-1: 2005(E) are taken to be those given in Table NA 1 under the heading of Physical Performance / Design, with the exception of:

Piercing of sign face; Edges of sign plates; and Corrosion protection.

A review of each requirement is given in the following sections.

3.8.2 Partial Action Factor

The partial action factor class is given as PAF1 in accordance with prEN 12899-1: 2005(E): Table 6; this defines the safety factors for ‘live’ and dead loads. Safety factors for materials are given in prEN 12899-1:

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 15

Wind Loading fir Signs to BS EN 12899

2005(E): Table 7. As the design of traffic signs is generally governed by ‘live’ loads, it is instructive to consider the overall factor of safety obtained by calculating the product of the partial factors on ‘live’ load and material strength (= γF.γm), as given in Table 8 below:

Material γF for PAF1 γm Overall FOS (γF.γm)

Steel 1.35 1.15 1.55

Aluminium 1.35 1.15 1.55

Timber 1.35 1.35 1.82

Fibre reinforced 1.35 1.50 2.03

Plastics 1.35 1.80 2.43

Table 8

An overall factor of safety for steel of 1.55 is consistent with the requirements of BS873: Part 7, which required steel to be designed in accordance with the requirements of BS449. Similarly, an overall factor of safety for aluminium of 1.55 is consistent with the requirements of BS873: Part 7, which required aluminium to be designed in accordance with the requirements of CP118. BS 873 did not cover signs made from timber. For comparison, reference was made to BS EN 1995-1.2: 2004 for the design of timber structures. Table 2.3 of this standard gave values of γm ranging from 1.2 for plywood to 1.3 for particleboard, fibreboard and solid timber. It is expected that traffic signs would be manufactured from solid timber and so the partial factor on material strength proposed in prEN 12899-1: 2005(E) appears slightly conservative. Similarly, BS 873 did not cover signs made from fibre reinforced polymer composite materials. For comparison with current UK practice, reference was made to BS EN 40-7 for the design of reinforced polymer composite lighting columns. Here, a partial factor on material strength of 1.5 is specified. BS EN 40-3-3, covering design and verification of lighting columns by calculation, specifies a partial factor on wind load of either 1.2 or 1.4, depending on structure class. This gives an overall factor of safety of between 1.80 and 2.10 for reinforced polymer composite lighting columns, which is comparable with the value of 2.03 given in Table 8. Finally, it should be noted that the ‘live’ loads given in prEN 12899-1: 2005(E) are based on a return period of 50 years. Care should be exercised when comparing the overall factors of safety for traffic signs to those for other highway structures where ‘live’ loads may be based on other return periods (e.g. 120 years for highway bridges).

3.8.3 Wind Load

Table NA 1 states that wind load with either be obtained from EN 1991-1-4 or by use of the appropriate wind pressure class. It is a minor point, but it should be noted that BS EN 1991-1-4 does not include meteorological information for the UK; this will be given in the UK National Annex to BS EN 1991-1-4, when published. For completeness, it is considered that the reference to the UK National Annex to BS EN 1991-1-4 should be included in Table NA 1.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 16

Wind Loading fir Signs to BS EN 12899

Table NA 1 recommends wind classes as follows:

Country Wind Class

England WL7

Northern Ireland WL8

Scotland WL8

Wales WL9

It is considered that: All of the classes given should only apply up to a limiting altitude of 250m above mean sea level. The classification for England is satisfactory, with the exception of the Isle of Man, where Class WL8

should apply; The classification for Northern Ireland should be WL9; The classification for Scotland should be WL9, subject to the exceptions given in Section 3.1 of this

report; and The classification for Wales is satisfactory.

3.8.4 Point Loads

The recommended Point Load Class is PL3. This is considered satisfactory.

3.8.5 Dynamic Snow Loads

Table NA 1 gives the following recommendations for Dynamic Snow Load Classes:

If snow blowers are not used Class DSL 0

When snow blowers are used class must depend on machinery used

(Highway Authority decision)

It is considered unwise to link the design of traffic signs to the use of snow blowers. Instead, it is considered that the decision whether to design for dynamic snow loads should be based on the following factors:

The likely occurrence of snow requiring clearance; and Whether clearance will be required in the event of significant snow fall (e.g. if the road is an

important transport link). The decision whether to use snow blowers may change several times during the design life of a traffic sign as a result of financial constraints on maintenance budgets or political decisions. However, the underlying climatic justification for designing for dynamic snow clearance loads is unlikely to change. It is considered that the HA should decide whether snow requiring clearance is likely to occur and whether the road is important enough to require clearance. If this is the case, then the classes recommended in

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 17

Wind Loading fir Signs to BS EN 12899

Section 3.4.3 should apply to the design of traffic signs. For clarity, these classes are reproducedat the top of the following page:

Road classification Dynamic snow load class (kN/m2)

Speed limit of 40mph or less DSL2

Speed limit greater than 40mph DSL4

3.8.6 Temporary Deflections

The recommended performance level for temporary deflections given in Table NA 1 are summarised below:

Product Bending Class Torsion Class

Support – Not passively safe (Class 0 in BS EN 12767)

TDB4 TDT4

Support – passively safe (Compliant with a performance class from BS EN 12767)

TDB5 TDT4

These match the text suggested for incorporation in a TA note, given in Annex A, Section A3. They will result in a relaxation of the temporary deflection requirements currently in use in the UK, as described in Section 3.3. above.

4 CONCLUSIONS

The principal conclusions drawn from the study are:

On the basis of the wind loading groups defined in BS EN 12899-1:2001, the most appropriate loading groups for application to UK conditions are WL7 for England and Wales and WL9 for Northern Ireland and Scotland based on a limiting altitude of 250m.

The design of support structures for the majority of typical signs encountered on the UK trunk road network will be governed by wind loading but it is clearly important to check that other defined loads are not more onerous.

The majority of signs erected on the UK trunk road network will be subject to WL7 loading. While the load effects generated will be marginally lower than those derived using the existing design standards, this is unlikely to result in a significant change in the size of the supporting post member selected during design.

Signs designed to WL9 loading will generate marginally higher load effects than those derived using the existing design standards. While this may result in slightly heavier post sections being selected, it is likely that the overall net increase to signage costs will be marginal.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 18

Wind Loading fir Signs to BS EN 12899

Significant economies can be made in the design of supporting structures where signs are sited at levels considerably below the limiting altitude by deriving site-specific wind loads.

The requirements given in prEN 12899-1: 2005(E) for temporary deflections are unchanged from those given in BS EN 12899-1: 2001. However, the recommended deflection classes have been revised so that they comply with the requirements of the standard. This will result in a relaxation of deflection limits when compared to previous designs to BS 873. Refer to Section 3.3.

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Page 19

Wind Loading fir Signs to BS EN 12899

Appendix I

Limiting Altitudes at Standard Wind Load Classes to BS EN 12899-1

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

FLINT & NEILL PARTNERSHIP PARSON'S BRINCKERHOFF

These tables give the limiting altitude below which a traffic sign designed to the standard "wind load" of either 1.4kPa or 1.6kPa is structurally acceptable.

Limiting Limiting Limiting Limiting Limiting Altitude (m) Altitude (m) Altitude (m) Altitude (m) Altitude (m)

at 1.4kPa at 1.4kPa at 1.6kPa at 1.4kPa at 1.6kPa(WL6) (WL6) (WL7) (WL7) (WL6)

Bath & North East Somerset 400 … Aberdeen 270 Blaenau Gwent 340 Antrim 250Bedfordshire 430 North East Lincolnshire 400 Aberdeenshire 240 Bridgend 320 Armagh 290Blackburn with Darwen 310 North Lincolnshire 400 Angus 290 Caerphilly 340 Down 290Blackpool 310 North Somerset 370 Argyll & Bute 150 Cardiff 340 Fermanagh 270Bournemouth 400 North Yorkshire 310 Clackmannanshire 320 Carmarthenshire 280 Londonderry 250Bracknell Forest 430 Northamptonshire 430 Dumfries & Galloway 280 Ceredigion 280 Tyrone 270Brighton & Hove 400 Northumberland 270 Dundee 330 Conwy 260Bristol 400 Nottingham 400 East Ayrshire 290 Denbighshire 280Buckinghamshire 430 Nottinghamshire 400 East Dunbartonshire 290 Flintshire 310Cambridgeshire 400 Oxfordshire 430 East Lothian 340 Gwynedd 250Channel Islands 280 Peterborough 400 East Renfrewshire 290 Isle of Anglesey 230Cheshire 340 Plymouth 280 Edinburgh 340 Merthyr Tydfil 320Cornwall 250 Poole 400 Falkirk 320 Monmouthshire 370Cumbria 260 Portsmouth 430 Fife 320 Neath Port Talbot 280Darlington 310 Reading 430 Glasgow 290 Newport 370Derby 400 Redcar & Cleveland 310 Highland 130 Pembrokeshire 260Derbyshire 400 Rutland 400 Inverclyde 270 Powys 310Devon 280 Shropshire 310 Midlothian 340 Rhondda Cynon taff 320Dorset 340 Slough 430 Moray 220 Swansea 300Durham 310 Somerset 310 North Ayrshire 250 Torfaen 370East Riding of Yorkshire 350 South Gloucestershire 400 North Lanarkshire 290 Vale of Glamorgan 320East Sussex 400 South Yorkshire 380 Orkney 120 Wrexham 340Essex 400 Southampton 430 Perth & Kinross 220Gloucestershire 400 Southend 400 Renfrewshire 270Greater London 430 Staffordshire 370 Scottish Borders 340Greater Manchester 340 Stockton-On-Tees 310 Shetland 70Halton 340 Stoke-On-Trent 370 South Ayrshire 280Hampshire 400 Suffolk 370 South Lanarkshire 290Hartlepool 310 Surrey 430 Stirling 270Herefordshire 340 Swindon 430 West Dunbartonshire 270Hertfordshire 430 Telford & Wrekin 310 West Lothian 320Isle of Wight 400 Thurrock 430 Western Isles 70Isles of Scilly 230 Torbay 310Kent 370 Tyne & Wear 280Kingston Upon Hull 370 Warrington 340Lancashire 280 Warwickshire 430Leicester 430 West Berkshire 430Leicestershire 420 West Midlands 430Lincolnshire 400 West Sussex 430Luton 430 West Yorkshire 370Medway 400 Wiltshire 420Merseyside 310 Windsor & Maidenhead 430Middlesbrough 310 Wokingham 430Milton Keynes 430 Worcestershire 370Norfolk 370 York 340

NB: The Isle of Man is a special case; the limiting altitude is 290m at 1.6kPa (WL7).

County/Unitary Authority Council County CountyCounty/Unitary Authority

England Scotland Wales Northern IrelandEngland (continued)

Task TC1/15 December 2004

Wind Loading fir Signs to BS EN 12899

ANNEX A

RECOMMENDATIONS FOR TEXT FOR INCORPORATION INTO A TA ADVICE NOTE

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

Wind Loading fir Signs to BS EN 12899

A.1 Selection of Design Wind Pressures

Traffic signs up to 9 metres in height should be designed to the following wind load classes given in Table A1, as given in BS EN 12899-1, provided the site is below the limiting altitude and the site is not classified as exposed:

Country Wind Load

Class to BS EN 12899-1

Limiting altitude (m AMSL)

England *1 WL7 250

Northern Ireland WL9 250

Scotland *2 WL9 250

Wales WL7 250

*1: With the exception of the Isle of Man, where wind load class WL8 shall apply. *2: With the exception of Argyll & Bute, Highland, Moray, Orkney, Perth & Kinross, Shetland and the Western Isles where wind loads shall be calculated for individual sites by application of BS EN 1991-1-4 and the UK National Annex.

Higher specific limiting altitudes may apply for individual Counties, Councils or Unitary Authority by reference to the tables in Appendix I. Site-specific wind load calculations to BS EN 1991-1-4 and the UK National Annex may be used if required. Examples where calculation may be required include:

Where the site altitude is higher than the specific limiting altitude given in Appendix I for the individual County, Council or Unitary Authority under consideration – site specific wind load calculations will be required to produce a safe design;

Where the site altitude is significantly below 250m – site specific wind load calculations may provide economy in design;

Where the site altitude is significantly below the specific limiting altitude given in Appendix I for the individual County, Council or Unitary Authority under consideration – site specific wind load calculations may provide economy in design;

Where signs are taller than 9 metres – site specific wind load calculations will be required to produce a safe design; or

Where signs are shorter than 9 metres – site-specific wind load calculations may provide economy in design.

A.2 Identification of Exposed and Sheltered Areas

Where local topography is significant (i.e. the upwind slope is greater that 0.05) then the provisions of BS EN 1991-1-4 and the UK National Annex for ‘orography’ shall apply and site-specific wind loads shall be calculated.

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

Wind Loading fir Signs to BS EN 12899

Where funnelling occurs, wind loads shall be factored accordingly. In valleys or high motorway embankments where local funnelling occurs, the wind load shall be multiplied by a funnelling factor, the value of which shall not be less than 1.2.

A.3 Deflection Classes

The revised text given below complies with the requirements of BS EN 12899-1. However, it will result in a relaxation of the deflection requirements currently used in the UK, as described in Section 3.3 of the Phase 2 Report: Traffic sign deflections shall meet the performance requirement classes of BS EN 12899-1 as given in Table A2 below:

Maximum temporary deflection class

Traffic Sign Type Bending (mm/m)

Torsion (degree/m)

Passively safe TDB5 TDT4

Not passively safe TDB4 TDT4

Table A2

Wind loads for calculating temporary deflections shall be in accordance with the requirements of BS EN 12899-1. Shape factors shall be determined from BS EN 1991-1-4 and the UK National Annex appropriate to the shape of the sign and post under consideration. To be considered as passively safe, a traffic sign shall comply with the requirements of TA 89/04 and BS EN 12767.

A.4 Advice on Loading Other Than Wind Loading

Point load class PL3 shall apply, as given in BS EN 12899-1. The decision to design for dynamic snow clearance loads shall rest with the Overseeing Organisation. However, where consideration of this load case is necessary, dynamic loads from snow clearance given in Table A3 below shall apply, as given in BS EN 12899-1: Clause 5.3.2. and Table 9.

Road classification Dynamic snow load class (kN/m2)

Speed limit of 40mph or less DSL2

Speed limit greater than 40mph DSL4

Table A3

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

Wind Loading fir Signs to BS EN 12899

ANNEX B

EXAMPLE CALCULATIONS

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

Design Calculations for a 750x450 signpost in accordance with BS EN 12899-1:2001

1. Sign and post sizes

h’

w

Ground Clearance (h’) 2300 mm

Sign Height (h) 450 mm

Sign width (w) 700 mm

No of posts 1

Post Diameter 76.1 mm

Post thickness 3.2 mm

h

2. Partial Factors

EC3 – table 1

γG, inf 1 Permanent actions favourable

γG, sup 1.1 Permanent actions favourable

γG, sup 1.35 Variable actions

γM0 1.1 Material Strength

3. Material and Sections Properties

fyd 250 MPa Steel grade

E 210000 N/mm2 Modulus of elasticity

G 81000 N/mm2 Shearing modulus

Z 12.8 cm3 Elastic modulus

I 48.8 cm4 Second moment of area

M 5.75 Kg/m Mass per meter

A 7.33 cm2 Cross sectional area

J 97.6 cm4

Where:

MPaf

fM

yyd 250

0

==γ

and

fy = 275 MPa (for this example)

1

4. Wind Loading

Wind Load class (WL)

As used for England

WL6 (1400) N/m2

Signboard: Cf = 1.8 *EN 1991-1-4 clause 7.4.3

Post: cf = 0.74 *EN 1991-1-4 clause 7.9.3

Where: κψ λ ⋅⋅= 0,ff cc

κ = 1 *EN 1991-1-4 table 7.14

ψλ = 0,91 *EN 1991-1-4 figure 7.36

φ = 1, λ = 36 *EN 1991-1-4 table 7.16

cf, 0 = 0.88 (for k = 0.02) *EN 1991-1-4 figure 7.28

5104.2Re ⋅=

⋅D=

vV

Where: 22 /140021 mNV =ρ smV /8.4714002

=⋅

and ν = 15 ⋅105, ρ = 1.226 Kg/m3

For L < 15 m, λ is:

bL

=λ or λ = 70

(whichever is larger)

Load on sign face: Wsign face = 1400 * 1.8 = 2520 kN/m2

Load on post: Wpost = 1400 * 0.74 = 1036 kN/m2

*This is the correct procedure to Eurocode. Alternatively (and conservatively) Cf,0 may be taken as 1.2 for circular posts, and 2.0 for rectangular posts.

Note: The pressure coefficient of 1.8 applies only to rectangular signs. If other shapes of signs are used, refer to EN 1991-1-4

bL

gallaj1
Highlight
gallaj1
Highlight
gallaj1
Highlight

5. Design Loads (for design of post)

W’post =Wpost * γG, sup 1890 N/m2

W’sign face =Wsign face * γG, sup 3402 N/m2

Moment max 3.1 kNm

Shear max 1.40 kN

Torsion 0.19 kNm

Torsional stress 7.30 N/mm2

Bending stress 241.1 N/mm2

Av 4.67 cm2

Shear Stress 3.00 N/mm2

Where, in this case: w

( EC3 – 5.4.6)

4maxbWhwTorsion signface ⋅⋅⋅= *

where: r = 76.1/2 mm

*Load accordingly applied as prescribed in EN 1991-1-4 c7.4.3

Moment capacity utilisation 96 %

Shear capacity utilisation 2.08%

Mmax

Smax

πAA 2

=v

( ) ( )

2''

2/''2

)(

max

hdw

hhwhwM

post

signface

⋅⋅

++⋅⋅⋅=

w/4

''' )()(max hdwwhwShear postsignface ⋅⋅+⋅⋅=

svAV

JrM

+⋅

⎟⎟⎠

⎞⎜⎜⎝

⎛=⎟

⎟⎠

⎞⎜⎜⎝

3 where y

y

y

ττ

=

6. Temporary Deflection of sign

W’sign face = Wsign face * 0.752 = 1417.5 N/m2

δ = 23.38 mm Where: (for current example)

or IE ⋅

⋅=3

δ LQ ⋅ 31

9.26 mm/m (δ/h) δ P

h

Classification: TDB3

(BS EN 12899 table 16)

Which satisfies the proposed (TDB4)

classification for the UK.

7. Design of post for Snow Loading

For the current example, the maximum shear 700

and moment would be:

2500

2000

( )

⎥⎦⎤

⎢⎣⎡ +

−⋅⋅⋅−

+⎥⎦⎤

⎢⎣⎡ +

−⋅⋅⋅−=

'2

'5.2)'5.2(

5.02

5.0')5.0'(max

hhwwh

hwdhM

s

s

ss wwhwdhShear ⋅⋅−+⋅⋅−= )'5.2()5.0'(max

Where: ws = 4 kN/m2 (DSL4)

The moment and shear capacity are:

19.30

==m

yuzfM

γ kNm > Mmax = 2.11 kNm Utilisation: 66%

==0m

vyu

AfVγ

67.38 kN > Vmax = 1.10 kN

Note: In the current example, the width of the sign is less than 2m, so the snow load is applied at the middle of the sign, for checking moment capacity. According to EN 12899 – ANNEX C the post should be checked for torsion as well.

( ) swwwhT ⋅⋅⋅−=42

'2500 700

2500

)'2500(2

hwwV s −⋅⋅=h

2/3.2 mmNAV

JrM

v

=+⋅

h’ 2max /32.145

3mmN

f yd ==σ

Where ws = 4 kN/m

2/275 mmNf yd =

Utilisation : 52%

Classification: DSL4 BS EN 12899 table 15

(As proposed for use in the UK)

8. Point Load

The point load of 1kN (PL5) is less Torsionthan the wind load, there is no need

to check the bending capacity of the post. 1 kN

Shear Force: V = 1 kN

Torsion: T = 1*(0.75/2) = 0.375 kNm

Shear Stress: 76.16max =+⋅

=vA

VJ

rMσ N/mm2

and

Shear Capacity of the post: 32.1453max == ydfσ N/mm2

Classification: PL5

* The calculated torsion value (T = 0.375 kNm) should also be used to check connection between signboard and post.

Calculation of wind load using EN 1991-1-4

Vb, map 22 m/s Fundamental wind velocity National Annex NA1

Site Altitude 50 m

calt 1.05 Altitude factor National Annex NA 2.4

Vb, 0 23.1 m/s Basic wind velocity National Annex NA 2.3

qb 327.1 Basic wind velocity pressure EN 1991-1-4 Eqn 4.10

cseason 1 Season factor National Annex NA 2

cdir 1 Direction factor National Annex NA 2.5

cr 0.75 Roughness factor National Annex NA 2.10

co 1 Orography factor National Annex NA 2.12

Iv (z) 0.195 National Annex NA 2.15

Vm (z) 17.325 m/s Mean wind velocity EN 1991-1-4 Eqn 4.3

qp 463.24 N/m2 Wind pressure National Annex NA 2.16

Note: cdir = 1 applies only to wind from the (SW) direction, so taking cdir equal to unity is

considered conservative.

cr = 0.75 is for a sign 2.75 m tall where the distance to the sea in the wind direction is

100 Km, and the terrain is classified as “ country terrain”

co = 1 considering that topography is not significant

Where: ρ = 1.226 Kg/m3 ( ) ( )[ ] ( ) bmvzp qzzvzI ⋅=⋅⋅+= 22 10,31 ρ

( )scq2

Vb,0 = vb,map * calt

2

21

bb vq ⋅⋅= ρ

borm vzczczv ⋅⋅= )()()(

Wind Loading fir Signs to BS EN 12899

ANNEX C

SUMMARY OF TRIAL CALCULATIONS

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

BS 873 BS EN 12899

Case 1 (No Cf) Case 2 (With Cf) Case 3 (WL6) Case 4 (WL7) Case 5 (At 50 altitude)

Size

Load

(KN

)

Load

Bas

e R

atio

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Mat

eria

l Rat

io

Load

(KN

)

Load

Bas

e R

atio

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Mat

eria

l Rat

io

Load

(KN

)

Load

Bas

e R

atio

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Mat

eria

l Rat

io

Load

(KN

)

Load

Bas

e R

atio

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Mat

eria

l Rat

io

Load

(KN

)

Load

Bas

e R

atio

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Mat

eria

l Rat

io

700x450 0.472 0.556 1 76.1 3.2 15.8 1.00 0.85 1.0 1 76.1 3.2 15.8 1.0 0.793 0.933 1 76.1 3.2 15.8 1.00 0.907 1.067 1 76.1 4 19.6 1.24 0.15 0.176 1 76.1 3.2 15.8 1.00

1250x1550 2.906 0.556 2 88.9 5 79.3 0.76 5.23 1.0 2 114.3 5 104 1.0 4.881 0.933 2 114.3 5 104 1.00 5.579 1.067 2 139.7 5 127 1.22 0.9 0.172 2 76.1 4 54.7 0.53

2300x4500 15.5 0.556 2 168.3 10 530 0.57 27.9 1.0 3 193.7 10 928 1.0 26.04 0.933 3 193.7 10 928 1.00 29.76 1.067 3 193.7 10 928 1.00 4.79 0.172 2 168.3 6.3 342 0.37

2900x2100 9.111 0.556 2 139.7 6.3 182 0.71 16.4 1.0 2 193.7 6.3 256 1.0 15.31 0.933 2 193.7 6.3 256 1.00 17.49 1.067 2 193.7 6.3 256 1.00 2.82 0.172 2 114.3 6.3 147 0.57

4000x3700 22.17 0.556 2 193.7 10 546 0.54 39.9 1.0 3 193.7 12.5 1006 1.0 37.24 0.933 3 193.7 12.5 1006 1.00 42.56 1.067 4 193.7 10 1092 1.09 6.85 0.172 2 193.7 6.3 349 0.35

5000x6500 48.72 0.556 4 193.7 16 1967 0.46 87.7 1.0 7 193.7 16 4318 1.0 81.85 0.933 7 193.7 16 4318 1.00 93.55 1.067 8 193.7 16 4935 1.14 15.1 0.172 3 193.7 12.5 1476 0.34

Table C1 - Comparison of Design Approaches of BS873 and BSEN 12899

BS 873 BS EN 12899 Proposals

Case 0 (Area 1)Case 1 (No Cf) Case 2 (With Cf) Case 3 (WL6) Case 4 (WL7) Case 5 (At 50 altitude)

Sign Dimensions (mm)

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Load

(KN

)

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Stee

l / A

1 st

eel (

1)

Load

(KN

)

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Stee

l / A

1 st

eel (

1)

Load

(KN

)

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Stee

l / A

1 st

eel

Load

(KN

)

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Stee

l / A

1 st

eel

Load

(KN

)

No

of p

osts

Sect

ion

DIA

(mm

)

Thic

knes

s (m

m)

Stee

l use

d (K

g)

Stee

l / A

1 st

eel

1650x1150 114.3 5 93.2 2.844 2 88.9 4 57.8 0.62 5.12 2 114.3 5 93.2 1 4.779 2 114.3 5 93.2 1.00 5.461 2 114.3 5 93.2 1.00 1.58 2 76.1 3.2 39.7 0.426

1750x1200 114.3 5 94.5 3.15 2 88.9 5 72.1 0.763 5.67 2 114.3 5 94.5 1 5.292 2 114.3 5 94.5 1.00 6.048 2 139.7 5 116.0 1.23 1.75 2 76.1 4 49.8 0.527

1825x1250 114.3 5 95.8 3.422 2 114.3 3.6 69.8 0.729 6.16 2 114.3 5 95.8 1 5.749 2 139.7 5 117.9 1.23 6.571 2 139.7 5 117.9 1.23 1.91 2 76.1 4 50.5 0.527

2000x1250 114.3 5 95.8 3.75 2 114.3 3.6 69.8 0.729 6.75 2 139.7 5 117.9 1.231 6.3 2 139.7 5 117.9 1.23 7.2 2 139.7 5 117.9 1.23 2.1 2 76.1 4 50.5 0.527

Table C2 - Comparison of Area 1 Standard Solutions

Wind Loading fir Signs to BS EN 12899

ANNEX D

SUPPLIMENTARY REPORT ON FOUNDATIONS

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

Flint & Neill Partnership Consulting Engineers

ww

w.f

lintn

eill.

co.u

k

PARSONS BRINCKERHOFF

Implementation of Eurocodes Wind Loading for Signs to BS EN 12899 Foundations

Task Report 970-3-Rp02-v1 April 2005

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 i April 2005

Document Control Sheet Rev. Status Date By Check Approved

0 Draft for comment 14-March-05 EJR BWS DKM

1 Minor revisions 19-Apr-05 EJR DKM DKM

Flint & Neill Partnership Stone, Berkeley, Gloucestershire GL13 9LB Tel: +44 (0) 1454 260910 Fax: +44 (0) 1454 260784 Email [email protected] Web: www.flintneill.co.uk Table of Contents:

1 Introduction ...................................................................................................................1 2 References ...................................................................................................................1

2.1 Standards ............................................................................................................1 2.2 Information Provided by Parsons Brinckerhoff .....................................................1

3 Tasks ............................................................................................................................2 3.1 Design of Planted Foundations ............................................................................2

3.1.1 Task Report............................................................................................2 3.1.2 Text for Incorporation into a TA Advice Note ..........................................4

3.2 Scope of Work – Concrete Block Foundations. ....................................................6 3.2.1 Overall Stability ......................................................................................6 3.2.2 Requirements for Concrete ....................................................................7 3.2.3 Connection to the Foundation ................................................................7

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 1 April 2005

1 Introduction

Flint & Neill Partnership were appointed by Parsons Brinckerhoff to provide advice

on the loading of traffic signs designed in accordance with BS EN 12899-1:2001.

A final version of Task Report 970-3-Rp01-v2 was submitted to Parsons Brinckerhoff

on the 11th January 2005. Following review of this report, Parsons Brinckerhoff

extended the scope of the original study to include advice on the design of planted

foundations and to prepare a scope of work for advice on the design of concrete

block foundations.

This report summarises the additional tasks undertaken and provides text for

incorporation in a TA advice note for the design of traffic signs.

2 References

2.1 Standards

• BD 26/04: Design of Lighting Columns (DMRB Volume 2, Section 2, Part 1)

• BS 5649: Part 2: 1978: Specification for lighting columns – dimensions and

tolerances

• BS EN 40-2: 2004: Lighting Columns – general requirements and dimensions

• BS EN 12899: Part 1: 2001: Fixed vertical road traffic signs

• PD 6547: 2004: Guidance on the use of BS EN 40-3-1 and BS EN 40-3-3

2.2 Information Provided by Parsons Brinckerhoff

• Area 1 Term Maintenance Contract - Table TS/2, Typical post types and

foundations;

• Standard traffic sign post & foundation sizes for small signs.

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 2 April 2005

3 Tasks

3.1 Design of Planted Foundations

3.1.1 Task Report

Highways Agency Departmental Standards and Advice Notes do not currently

contain guidance on the design of planted foundations for traffic signs. It was

considered that advice currently given in PD 6547 for the design of planted

foundations for lighting columns may be suitable. It should be noted that the advice

in PD 6547 was taken directly from BS 5649: Part 2: 1978 (also known as EN 40-2).

Planting of traffic signs is similar to planting of lighting columns in that the post

inserted in the ground is cylindrical (or polygonal) and the structure is cantilevered

above ground level. Although traffic signs can have multiple posts, they can still be

considered as individual cantilevers for the critical direction of load applied

perpendicular to the face of the signboard. Differences arise in the size of the post.

Lighting column bases are typically 168mm diameter or larger; this allows space for

electrical equipment at the lighting column base (and access to it through a cut-out in

the cross-section). Traffic sign posts are typically 76mm diameter or larger; they

generally only need to satisfy strength and stiffness requirements and do not have

cut-outs near the base. Thus, for a given overturning moment, the diameter of a

traffic sign post is likely to be smaller than the diameter of a lighting column. It

follows that traffic sign posts will need to be planted to a greater depth than lighting

columns or require an increase in the effective diameter of the planted section.

However, it is considered that the design guidance in PD 6547 for planting of lighting

columns can be applied to planting of traffic sign posts.

The proposed rules are included in Section 3.1.2; they have been taken directly from

PD 6547 with the following minor amendments:

• For lighting columns, the planting depth should be selected from the centre

column of BS EN 40-2: 2004: Table 7. Given that road sign posts will

generally be of a smaller diameter and require a greater planting depth, the

guidance in Section 3.1.2 states that the planting depth should be selected

from the right-hand column of this table, where planting depths are greater.

• The requirement for a duct in the back-fill material to provide access for

electrical cable has been removed.

• A number of minor grammatical changes have been made to improve clarity.

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 3 April 2005

In order to test the proposed rules, they were applied to a representative sample of

66 traffic signs. These were selected from standard designs; a copy of the data

forming the sample set is included in Appendix I. Calculations were performed on

the following basis:

• A design wind pressure of 1.6kPa was used (corresponding to BS EN 12899-

1 Class WL7). This is the recommended value for Scotland and Northern

Ireland.

• A drag factor of 1.8 was applied – it is considered that this is an upper bound

value given the aspect ratio of most traffic signboards.

Calculations were undertaken for the following combination of planted depths and

increase to the diameter of the planted post; a summary of the results is included in

Appendix II:

Combination Planted depth Increase to diameter of post

1 0.8m 0

2 0.8m +0.1m

3 0.8m +0.2m

4 1.0m 0

5 1.0m +0.1m

6 1.0m +0.2m

It should be noted that a planted depth of 0.8m corresponds to the value that would

be used for a lighting column of height up to 5m (centre column of BS EN 40-2:

2004: Table 7). A planted depth of 1.0m corresponds to the value recommended for

a traffic sign post of height up to 5m (right-hand column of BS EN 40-2: 2004: Table

7).

The proportion of the sample resulting in adequate planted foundations can be

summarised as follows:

Combination % of Adequate Planted Foundations

1 3%

2 30%

3 55%

4 20%

5 69%

6 87%

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 4 April 2005

Closer examination of the results in Appendix II shows that enhancement of the

effective diameter will be required in the majority of cases to achieve an adequate

foundation. Combination 1, 2 and 3 show that a planted depth of 0.8m will usually

be inadequate. Combination 4 shows that an enhancement of the effective diameter

will be required in all but the smallest and shortest traffic signs. Combination 5 gives

acceptable results in all ‘good’ ground conditions and most ‘average’ ground

conditions. Unacceptable results occur in ‘poor’ ground conditions and for large, tall

signs where a concrete base is likely to be the preferred solution. Combination 6

shows the benefit of increasing the effective diameter of the planted post, even

giving an acceptable solution in most ‘poor’ ground conditions.

3.1.2 Text for Incorporation into a TA Advice Note

Planting Depth:

Where a traffic sign is to be planted in the ground, the planting depth shall be

selected from the right-hand column of BS EN 40-2: 2004: Table 7, taking into

account the height to the top of the traffic sign.

To check the adequacy of the selected planting depth, taking account of the ground

conditions at the site, it is recommended that the calculation procedure given below

is adopted.

Calculation of Applied Moment and Ground Resistance Moment:

The greatest overturning moment, MOT, arising from application of the un-factored

design loads (e.g. wind load or dynamic load from snow clearance) to the traffic sign

and its supports should either be calculated or obtained from the traffic sign

designer. The overturning moment shall be calculated about a fulcrum point located

at 1/√2 of the planting depth.

The overturning moment shall be multiplied by a factor of safety, γF, of 1.25.

The ground resistance moment, Mg, should be calculated using the following

formula:

10

PDGM

3

g××

=

Where:

G is a factor dependent on the ground in which the column is planted (in kN/m2 per m). Refer to the table below for typical values of G.

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 5 April 2005

D is the minimum diameter (or minimum distance across flats for multi-sided sections) of the traffic sign in the ground (in m).

P is the planting depth.

The planting depth is satisfactory if γF .MOT < Mg

If this criterion is not satisfied then the planting depth shall be increased and/or the

effective diameter of the traffic sign post shall be increased. The latter can be

achieved by backfilling the excavation hole with mass concrete or an appropriate fill

material (refer to ‘Back-filling’ below); the effective diameter of the traffic sign post

may then be taken as the minimum diameter of the excavation hole.

Table: Ground Factor G:

G (kN/m2 per m)

Quality of soil

630 Good: Compact, well-graded sand and gravel, hard clay, well-graded fine and coarse sand, decomposed granite rock and soil.

Good soils drain well.

390 Average: Compact fine sand, medium clay, compact well drained sandy loam, loose coarse sand and gravels.

Average soils drain sufficiently well that water does not stand on the surface.

230 Poor: Soft clay, clay loam, poorly compacted sand, clays containing a large amount of silt and vegetable matter, and made-up ground.

Poor soils are normally wet and have poor drainage.

Back-filling:

The calculation of ground resistance moment, Mg, is based on the excavated hole

into which the traffic sign post is planted being back-filled with the excavated

material or material of better quality.

The following should be specified to the installer:

a) All back-filling material shall be placed in 150mm thick layers and well

compacted;

b) During compaction, care shall be taken to ensure that the corrosion protection

system for the traffic sign post is not damaged;

c) Where the excavated hole is back-filled with concrete, the concrete shall extend

from the base of the traffic sign post to ground level; and

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 6 April 2005

d) Where paving or bituminous surfacing is to be applied around the lighting column,

the top level of the concrete may be lowered by the thickness of the surfacing.

3.2 Scope of Work – Concrete Block Foundations.

Highways Agency Departmental Standards and Advice Notes do not currently

contain guidance on the design of concrete block foundations for traffic signs.

Furthermore, design guidance is not given for other similar structures that could be

adapted for traffic signs. Thus, a scope of work is presented to establish the steps

required to draft adequate design guidance. They fall under the following headings:

3.2.1 Overall Stability

A concrete block foundation supporting a cantilevered structure such as a traffic sign

will need to provide adequate stability against overturning. Also, the bearing

pressure beneath the block must not exceed the capacity of the ground. Given the

form of loading, uplift will not occur and sliding is highly unlikely to govern.

Design guidance on stability should include:

• Clear guidance on the calculation of overturning moments (it is a common

error to calculate moments at the base of the traffic sign rather than at the

assumed level of the point of rotation).

• A simple and conservative method of calculating resistance to overturning. It

is expected that this will be based on the mass of the block and an assumed

point of rotation.

Uplift Sliding

Overturning Bearing Pressure

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 7 April 2005

• Reference to standard methods for calculating bearing pressures (note that

the method used depends on whether the bearing pressure becomes zero on

the upwind side – as illustrated above).

• Guidance on allowable bearing pressures, appropriate to the ‘good’,

‘average’ and ‘poor’ ground classifications given for the design of planted

foundations (refer to Section 3.1.2).

Guidance will need to be reviewed for compliance with the forthcoming Eurocodes

(in particular EN1997-1).

3.2.2 Requirements for Concrete

It is considered that minimum requirements should be given for:

• Grade of concrete (use of standard mix designs would be preferable); and

• Reinforcement.

The need of reinforcement will depend on the size of the block, the imposed loads

and the method of attachment of the post. It is likely that the smallest blocks (e.g. for

speed limit repeater signs) will not require reinforcement at all. Larger blocks may

require anti-crack reinforcement and the largest blocks may require structural

reinforcement. Guidance should be given on determining what reinforcement is

required to allow it to be designed.

3.2.3 Connection to the Foundation

It is essential that the connection of the traffic sign post to the concrete block

foundation is structurally sound. It is understood that cast-in sockets are commonly

used and it is expected that the largest sign posts may use flange plate connections:

Cast-in sockets:

Guidance will be needed on the following aspects:

• The depth of the socket;

• End bearing on the underside of the post;

• Provision of service ducts, where the signs carry electrical services (e.g. for

lighting); and

• Corrosion protection at the post/foundation interface.

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 Page 8 April 2005

Flange Plates:

There is considerable guidance given in BD26/04 for the design of lighting column

flange plate connections. It is considered that this may be used as an appropriate

basis for the development of design guidance on flange plate connection for traffic

sign posts. Guidance will be needed on the following aspects:

• Design for vehicle impact;

• Design of the post to flange-plate connection, with guidance on both static

strength and providing a good fatigue resistant design;

• Design of the holding down bolts, including their anchorage in the concrete

block;

• Design of the grout beneath the flange plate;

• Corrosion protection to the holding down bolts and the flange plate;

• Use of levelling nuts and the implications for design of the flange plates and

the holding down bolts.

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 April 2005

Appendix I

Sample Traffic Signs

Standard Sign Area GuideSign Areas ( Sq M )

Size (mm) Square Circle Triangle450 0.2 0.16 0.12600 0.36 0.28 0.21750 0.57 0.44 0.33900 0.81 0.64 0.47

1200 1.44 1.13 0.831500 2.55 1.76 1.33

Single Post FoundationsPost Size Foundation Size ( mm )Dia (mm) Width Length Depth76.1 x 3.2 900 900 60088.9 x 4 1000 1000 600114.3 x 5 1100 1100 700139.7 x 5 1400 1400 800168.3 x 5 1000 1800 1000

Combined Foundations Dependant On Post Spacing

Post SizesHeight To Area Of Sign ( Sq Metre )Centre Of 0.25 0.50 0.80 1.00 1.50 2.00Sign (M) One Post One Post One Post Two Posts One Post Two Posts One Post Two Posts One Post Two Posts

1.2 1 x 76.1 1 x 76.1 1 x 76.1 2 x 76.1 1 x 76.1 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 76.1(1 x 88.9)

1.4 1 x 76.1 1 x 76.1 1 x 76.1 2 x 76.1 1 x 76.1 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9(2 x 76.1)

1.6 1 x 76.1 1 x 76.1 1 x 76.1 2 x 76.1 1 x 76.1 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9

1.8 1 x 76.1 1 x 76.1 1 x 76.1 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 88.9(1 x 88.9)

2.0 1 x 76.1 1 x 76.1 1 x 76.1 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 88.9

2.2 1 x 76.1 1 x 76.1 1 x 88.9 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 114.3

2.4 1 x 76.1 1 x 76.1 1 x 88.9 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 114.3

2.6 1 x 76.1 1 x 76.1 1 x 88.9 2 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 114.3

2.8 1 x 76.1 1 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 88.9 1 x 114.3 2 x 114.3(1 x 88.9)

3.0 1 x 76.1 1 x 76.1 1 x 88.9 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 88.9 1 x 139.7 2 x 114.3(1 x 114.3)

3.2 1 x 76.1 1 x 88.9 1 x 114.3 2 x 76.1 1 x 114.3 2 x 88.9 1 x 114.3 2 x 114.3 1 x 139.7 2 x 114.3(1 x 88.9)

Table is based on wind loading of 1.5Kn/M2 & combined factor of safety of 1.5Figures in bracketed Italics based on a reduced wind loading of 1.2 Kn/M2See foundation size table for post wall thickness

Socket SizesPost Size Socket SocketDia (mm) Dia (mm) Depth

140 300 900194 350 950219 375 975244 400 1000273 425 1025

Flint & Neill Partnership Parsons Brinckerhoff

970-3-Rp02-v1 April 2005

Appendix II

Calculations for Planted Foundations

Client: PB Planted Foundations for Traffic Signs

Assessment of Rules in PD6547

Job 970/314/03/2005

EJR

Addition to diameter to account for augered hole: 0 m

Sign Drag Wind FOS Wind Planting Height to Lever No. of Moment Post EffectiveArea Factor Pressure Load Depth Centre of Arm Posts about Dia Dia Good Average Poor Good Average Poor(m2) (kPa) (kN) (m) Sign (m) fulcrum (m) Dia (630) (390) (230) (630) (390) (230)

(m) (kNm) (m)

0.25 1.8 1.6 1.25 0.9 0.8 1.2 1.77 1 1.59 0.076 0.076 2.451 1.518 0.895 OK Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 1.4 1.97 1 1.77 0.076 0.076 2.451 1.518 0.895 OK Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 1.6 2.17 1 1.95 0.076 0.076 2.451 1.518 0.895 OK Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 1.8 2.37 1 2.13 0.076 0.076 2.451 1.518 0.895 OK Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 2 2.57 1 2.31 0.076 0.076 2.451 1.518 0.895 OK Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 2.2 2.77 1 2.49 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 2.4 2.97 1 2.67 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 2.6 3.17 1 2.85 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 2.8 3.37 1 3.03 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 3 3.57 1 3.21 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.25 1.8 1.6 1.25 0.9 0.8 3.2 3.77 1 3.39 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails

0.5 1.8 1.6 1.25 1.8 0.8 1.2 1.77 1 3.18 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 1.4 1.97 1 3.54 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 1.6 2.17 1 3.90 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 1.8 2.37 1 4.26 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2 2.57 1 4.62 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.2 2.77 1 4.98 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.4 2.97 1 5.34 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.6 3.17 1 5.70 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.8 3.37 1 6.06 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 3 3.57 1 6.42 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 3.2 3.77 1 6.78 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails

0.8 1.8 1.6 1.25 2.88 0.8 1.2 1.77 1 5.09 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.4 1.97 1 5.66 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.6 2.17 1 6.24 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.8 2.37 2 3.41 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2 2.57 2 3.69 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.2 2.77 2 3.98 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.4 2.97 2 4.27 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.6 3.17 2 4.56 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.8 3.37 2 4.85 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 3 3.57 2 5.13 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 3.2 3.77 2 5.42 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails

1 1.8 1.6 1.25 3.6 0.8 1.2 1.77 2 3.18 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 1.4 1.97 2 3.54 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 1.6 2.17 2 3.90 0.076 0.076 2.451 1.518 0.895 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 1.8 2.37 2 4.26 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 2 2.57 2 4.62 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.2 2.77 2 4.98 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.4 2.97 2 5.34 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.6 3.17 2 5.70 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.8 3.37 2 6.06 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 3 3.57 2 6.42 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 3.2 3.77 2 6.78 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails

1.5 1.8 1.6 1.25 5.4 0.8 1.2 1.77 2 4.77 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.4 1.97 2 5.31 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.6 2.17 2 5.85 0.089 0.089 2.868 1.775 1.047 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.8 2.37 2 6.39 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2 2.57 2 6.93 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.2 2.77 2 7.47 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.4 2.97 2 8.01 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.6 3.17 2 8.55 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.8 3.37 2 9.09 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 3 3.57 2 9.63 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 3.2 3.77 2 10.17 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails

2 1.8 1.6 1.25 7.2 0.8 1.2 1.77 2 6.36 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.4 1.97 2 7.08 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.6 2.17 2 7.80 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.8 2.37 2 8.52 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2 2.57 2 9.24 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.2 2.77 2 9.96 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.4 2.97 2 10.68 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.6 3.17 2 11.40 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.8 3.37 2 12.12 0.114 0.114 3.687 2.282 1.346 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 3 3.57 2 12.84 0.140 0.140 4.506 2.790 1.645 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 3.2 3.77 2 13.56 0.140 0.140 4.506 2.790 1.645 Fails Fails Fails

Number of "OK" foundations: 5 3%Number of "Failed" foundations: 193 97%

Ground resistance moment, Mg Ground resistance moment, Mg

FLINT & NEILL PARTNERSHIP Page 1 of 1 Planting depths

Client: PB Planted Foundations for Traffic Signs

Assessment of Rules in PD6547

Job 970/314/03/2005

EJR

Addition to diameter to account for augered hole: 0.1 m

Sign Drag Wind FOS Wind Planting Height to Lever No. of Moment Post EffectiveArea Factor Pressure Load Depth Centre of Arm Posts about Dia Dia Good Average Poor Good Average Poor(m2) (kPa) (kN) (m) Sign (m) fulcrum (m) Dia (630) (390) (230) (630) (390) (230)

(m) (kNm) (m)

0.25 1.8 1.6 1.25 0.9 0.8 1.2 1.77 1 1.59 0.076 0.176 5.677 3.514 2.073 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 1.4 1.97 1 1.77 0.076 0.176 5.677 3.514 2.073 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 1.6 2.17 1 1.95 0.076 0.176 5.677 3.514 2.073 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 1.8 2.37 1 2.13 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 2 2.57 1 2.31 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 2.2 2.77 1 2.49 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 2.4 2.97 1 2.67 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 2.6 3.17 1 2.85 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 2.8 3.37 1 3.03 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 3 3.57 1 3.21 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.25 1.8 1.6 1.25 0.9 0.8 3.2 3.77 1 3.39 0.076 0.176 5.677 3.514 2.073 OK OK Fails

0.5 1.8 1.6 1.25 1.8 0.8 1.2 1.77 1 3.18 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 1.4 1.97 1 3.54 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 1.6 2.17 1 3.90 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 1.8 2.37 1 4.26 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2 2.57 1 4.62 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.2 2.77 1 4.98 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.4 2.97 1 5.34 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.6 3.17 1 5.70 0.076 0.176 5.677 3.514 2.073 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.8 3.37 1 6.06 0.076 0.176 5.677 3.514 2.073 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 3 3.57 1 6.42 0.076 0.176 5.677 3.514 2.073 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 3.2 3.77 1 6.78 0.089 0.189 6.093 3.772 2.224 Fails Fails Fails

0.8 1.8 1.6 1.25 2.88 0.8 1.2 1.77 1 5.09 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.4 1.97 1 5.66 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.6 2.17 1 6.24 0.076 0.176 5.677 3.514 2.073 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.8 2.37 2 3.41 0.076 0.176 5.677 3.514 2.073 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 2 2.57 2 3.69 0.076 0.176 5.677 3.514 2.073 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.2 2.77 2 3.98 0.089 0.189 6.093 3.772 2.224 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.4 2.97 2 4.27 0.089 0.189 6.093 3.772 2.224 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.6 3.17 2 4.56 0.089 0.189 6.093 3.772 2.224 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 2.8 3.37 2 4.85 0.089 0.189 6.093 3.772 2.224 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 3 3.57 2 5.13 0.089 0.189 6.093 3.772 2.224 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 3.2 3.77 2 5.42 0.089 0.189 6.093 3.772 2.224 OK Fails Fails

1 1.8 1.6 1.25 3.6 0.8 1.2 1.77 2 3.18 0.076 0.176 5.677 3.514 2.073 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 1.4 1.97 2 3.54 0.076 0.176 5.677 3.514 2.073 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 1.6 2.17 2 3.90 0.076 0.176 5.677 3.514 2.073 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 1.8 2.37 2 4.26 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 2 2.57 2 4.62 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.2 2.77 2 4.98 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.4 2.97 2 5.34 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.6 3.17 2 5.70 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 2.8 3.37 2 6.06 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 3 3.57 2 6.42 0.089 0.189 6.093 3.772 2.224 Fails Fails Fails1 1.8 1.6 1.25 3.6 0.8 3.2 3.77 2 6.78 0.089 0.189 6.093 3.772 2.224 Fails Fails Fails

1.5 1.8 1.6 1.25 5.4 0.8 1.2 1.77 2 4.77 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.4 1.97 2 5.31 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.6 2.17 2 5.85 0.089 0.189 6.093 3.772 2.224 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.8 2.37 2 6.39 0.114 0.214 6.912 4.279 2.524 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2 2.57 2 6.93 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.2 2.77 2 7.47 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.4 2.97 2 8.01 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.6 3.17 2 8.55 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.8 3.37 2 9.09 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 3 3.57 2 9.63 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 3.2 3.77 2 10.17 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails

2 1.8 1.6 1.25 7.2 0.8 1.2 1.77 2 6.36 0.114 0.214 6.912 4.279 2.524 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.4 1.97 2 7.08 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.6 2.17 2 7.80 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.8 2.37 2 8.52 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2 2.57 2 9.24 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.2 2.77 2 9.96 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.4 2.97 2 10.68 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.6 3.17 2 11.40 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.8 3.37 2 12.12 0.114 0.214 6.912 4.279 2.524 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 3 3.57 2 12.84 0.140 0.240 7.732 4.786 2.823 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 3.2 3.77 2 13.56 0.140 0.240 7.732 4.786 2.823 Fails Fails Fails

Number of "OK" foundations: 59 30%Number of "Failed" foundations: 139 70%

Ground resistance moment, Mg Ground resistance moment, Mg

FLINT & NEILL PARTNERSHIP Page 1 of 1 Planting depths

Client: PB Planted Foundations for Traffic Signs

Assessment of Rules in PD6547

Job 970/314/03/2005

EJR

Addition to diameter to account for augered hole: 0.2 m

Sign Drag Wind FOS Wind Planting Height to Lever No. of Moment Post EffectiveArea Factor Pressure Load Depth Centre of Arm Posts about Dia Dia Good Average Poor Good Average Poor(m2) (kPa) (kN) (m) Sign (m) fulcrum (m) Dia (630) (390) (230) (630) (390) (230)

(m) (kNm) (m)

0.25 1.8 1.6 1.25 0.9 0.8 1.2 1.77 1 1.59 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 1.4 1.97 1 1.77 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 1.6 2.17 1 1.95 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 1.8 2.37 1 2.13 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 2 2.57 1 2.31 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 2.2 2.77 1 2.49 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 2.4 2.97 1 2.67 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 2.6 3.17 1 2.85 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 2.8 3.37 1 3.03 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 3 3.57 1 3.21 0.076 0.276 8.903 5.511 3.250 OK OK OK0.25 1.8 1.6 1.25 0.9 0.8 3.2 3.77 1 3.39 0.076 0.276 8.903 5.511 3.250 OK OK Fails

0.5 1.8 1.6 1.25 1.8 0.8 1.2 1.77 1 3.18 0.076 0.276 8.903 5.511 3.250 OK OK OK0.5 1.8 1.6 1.25 1.8 0.8 1.4 1.97 1 3.54 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 1.6 2.17 1 3.90 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 1.8 2.37 1 4.26 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 2 2.57 1 4.62 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 2.2 2.77 1 4.98 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 2.4 2.97 1 5.34 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.5 1.8 1.6 1.25 1.8 0.8 2.6 3.17 1 5.70 0.076 0.276 8.903 5.511 3.250 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 2.8 3.37 1 6.06 0.076 0.276 8.903 5.511 3.250 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 3 3.57 1 6.42 0.076 0.276 8.903 5.511 3.250 OK Fails Fails0.5 1.8 1.6 1.25 1.8 0.8 3.2 3.77 1 6.78 0.089 0.289 9.319 5.769 3.402 OK Fails Fails

0.8 1.8 1.6 1.25 2.88 0.8 1.2 1.77 1 5.09 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 1.4 1.97 1 5.66 0.076 0.276 8.903 5.511 3.250 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.6 2.17 1 6.24 0.076 0.276 8.903 5.511 3.250 OK Fails Fails0.8 1.8 1.6 1.25 2.88 0.8 1.8 2.37 2 3.41 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 2 2.57 2 3.69 0.076 0.276 8.903 5.511 3.250 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 2.2 2.77 2 3.98 0.089 0.289 9.319 5.769 3.402 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 2.4 2.97 2 4.27 0.089 0.289 9.319 5.769 3.402 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 2.6 3.17 2 4.56 0.089 0.289 9.319 5.769 3.402 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 2.8 3.37 2 4.85 0.089 0.289 9.319 5.769 3.402 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 3 3.57 2 5.13 0.089 0.289 9.319 5.769 3.402 OK OK Fails0.8 1.8 1.6 1.25 2.88 0.8 3.2 3.77 2 5.42 0.089 0.289 9.319 5.769 3.402 OK OK Fails

1 1.8 1.6 1.25 3.6 0.8 1.2 1.77 2 3.18 0.076 0.276 8.903 5.511 3.250 OK OK OK1 1.8 1.6 1.25 3.6 0.8 1.4 1.97 2 3.54 0.076 0.276 8.903 5.511 3.250 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 1.6 2.17 2 3.90 0.076 0.276 8.903 5.511 3.250 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 1.8 2.37 2 4.26 0.089 0.289 9.319 5.769 3.402 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 2 2.57 2 4.62 0.089 0.289 9.319 5.769 3.402 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 2.2 2.77 2 4.98 0.089 0.289 9.319 5.769 3.402 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 2.4 2.97 2 5.34 0.089 0.289 9.319 5.769 3.402 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 2.6 3.17 2 5.70 0.089 0.289 9.319 5.769 3.402 OK OK Fails1 1.8 1.6 1.25 3.6 0.8 2.8 3.37 2 6.06 0.089 0.289 9.319 5.769 3.402 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 3 3.57 2 6.42 0.089 0.289 9.319 5.769 3.402 OK Fails Fails1 1.8 1.6 1.25 3.6 0.8 3.2 3.77 2 6.78 0.089 0.289 9.319 5.769 3.402 OK Fails Fails

1.5 1.8 1.6 1.25 5.4 0.8 1.2 1.77 2 4.77 0.089 0.289 9.319 5.769 3.402 OK OK Fails1.5 1.8 1.6 1.25 5.4 0.8 1.4 1.97 2 5.31 0.089 0.289 9.319 5.769 3.402 OK OK Fails1.5 1.8 1.6 1.25 5.4 0.8 1.6 2.17 2 5.85 0.089 0.289 9.319 5.769 3.402 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 1.8 2.37 2 6.39 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2 2.57 2 6.93 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.2 2.77 2 7.47 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.4 2.97 2 8.01 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.6 3.17 2 8.55 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 2.8 3.37 2 9.09 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 3 3.57 2 9.63 0.114 0.314 10.138 6.276 3.701 OK Fails Fails1.5 1.8 1.6 1.25 5.4 0.8 3.2 3.77 2 10.17 0.114 0.314 10.138 6.276 3.701 Fails Fails Fails

2 1.8 1.6 1.25 7.2 0.8 1.2 1.77 2 6.36 0.114 0.314 10.138 6.276 3.701 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.4 1.97 2 7.08 0.114 0.314 10.138 6.276 3.701 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.6 2.17 2 7.80 0.114 0.314 10.138 6.276 3.701 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 1.8 2.37 2 8.52 0.114 0.314 10.138 6.276 3.701 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 2 2.57 2 9.24 0.114 0.314 10.138 6.276 3.701 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.2 2.77 2 9.96 0.114 0.314 10.138 6.276 3.701 OK Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.4 2.97 2 10.68 0.114 0.314 10.138 6.276 3.701 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.6 3.17 2 11.40 0.114 0.314 10.138 6.276 3.701 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 2.8 3.37 2 12.12 0.114 0.314 10.138 6.276 3.701 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 3 3.57 2 12.84 0.140 0.340 10.957 6.783 4.000 Fails Fails Fails2 1.8 1.6 1.25 7.2 0.8 3.2 3.77 2 13.56 0.140 0.340 10.957 6.783 4.000 Fails Fails Fails

Number of "OK" foundations: 109 55%Number of "Failed" foundations: 89 45%

Ground resistance moment, Mg Ground resistance moment, Mg

FLINT & NEILL PARTNERSHIP Page 1 of 1 Planting depths

Client: PB Planted Foundations for Traffic Signs

Assessment of Rules in PD6547

Job 970/314/03/2005

EJR

Addition to diameter to account for augered hole: 0 m

Sign Drag Wind FOS Wind Planting Height to Lever No. of Moment Post EffectiveArea Factor Pressure Load Depth Centre of Arm Posts about Dia Dia Good Average Poor Good Average Poor(m2) (kPa) (kN) (m) Sign (m) fulcrum (m) Dia (630) (390) (230) (630) (390) (230)

(m) (kNm) (m)

0.25 1.8 1.6 1.25 0.9 1 1.2 1.91 1 1.72 0.076 0.076 4.788 2.964 1.748 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.4 2.11 1 1.90 0.076 0.076 4.788 2.964 1.748 OK OK Fails0.25 1.8 1.6 1.25 0.9 1 1.6 2.31 1 2.08 0.076 0.076 4.788 2.964 1.748 OK OK Fails0.25 1.8 1.6 1.25 0.9 1 1.8 2.51 1 2.26 0.076 0.076 4.788 2.964 1.748 OK OK Fails0.25 1.8 1.6 1.25 0.9 1 2 2.71 1 2.44 0.076 0.076 4.788 2.964 1.748 OK OK Fails0.25 1.8 1.6 1.25 0.9 1 2.2 2.91 1 2.62 0.076 0.076 4.788 2.964 1.748 OK OK Fails0.25 1.8 1.6 1.25 0.9 1 2.4 3.11 1 2.80 0.076 0.076 4.788 2.964 1.748 OK OK Fails0.25 1.8 1.6 1.25 0.9 1 2.6 3.31 1 2.98 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.25 1.8 1.6 1.25 0.9 1 2.8 3.51 1 3.16 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.25 1.8 1.6 1.25 0.9 1 3 3.71 1 3.34 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.25 1.8 1.6 1.25 0.9 1 3.2 3.91 1 3.52 0.076 0.076 4.788 2.964 1.748 OK Fails Fails

0.5 1.8 1.6 1.25 1.8 1 1.2 1.91 1 3.43 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.5 1.8 1.6 1.25 1.8 1 1.4 2.11 1 3.79 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.5 1.8 1.6 1.25 1.8 1 1.6 2.31 1 4.15 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.5 1.8 1.6 1.25 1.8 1 1.8 2.51 1 4.51 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.5 1.8 1.6 1.25 1.8 1 2 2.71 1 4.87 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 1 2.2 2.91 1 5.23 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 1 2.4 3.11 1 5.59 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 1 2.6 3.31 1 5.95 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 1 2.8 3.51 1 6.31 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 1 3 3.71 1 6.67 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.5 1.8 1.6 1.25 1.8 1 3.2 3.91 1 7.03 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails

0.8 1.8 1.6 1.25 2.88 1 1.2 1.91 1 5.49 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 1 1.4 2.11 1 6.07 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 1 1.6 2.31 1 6.64 0.076 0.076 4.788 2.964 1.748 Fails Fails Fails0.8 1.8 1.6 1.25 2.88 1 1.8 2.51 2 3.61 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 2 2.71 2 3.90 0.076 0.076 4.788 2.964 1.748 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 2.2 2.91 2 4.19 0.089 0.089 5.601 3.467 2.045 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 2.4 3.11 2 4.47 0.089 0.089 5.601 3.467 2.045 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 2.6 3.31 2 4.76 0.089 0.089 5.601 3.467 2.045 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 2.8 3.51 2 5.05 0.089 0.089 5.601 3.467 2.045 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 3 3.71 2 5.34 0.089 0.089 5.601 3.467 2.045 OK Fails Fails0.8 1.8 1.6 1.25 2.88 1 3.2 3.91 2 5.63 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails

1 1.8 1.6 1.25 3.6 1 1.2 1.91 2 3.43 0.076 0.076 4.788 2.964 1.748 OK Fails Fails1 1.8 1.6 1.25 3.6 1 1.4 2.11 2 3.79 0.076 0.076 4.788 2.964 1.748 OK Fails Fails1 1.8 1.6 1.25 3.6 1 1.6 2.31 2 4.15 0.076 0.076 4.788 2.964 1.748 OK Fails Fails1 1.8 1.6 1.25 3.6 1 1.8 2.51 2 4.51 0.089 0.089 5.601 3.467 2.045 OK Fails Fails1 1.8 1.6 1.25 3.6 1 2 2.71 2 4.87 0.089 0.089 5.601 3.467 2.045 OK Fails Fails1 1.8 1.6 1.25 3.6 1 2.2 2.91 2 5.23 0.089 0.089 5.601 3.467 2.045 OK Fails Fails1 1.8 1.6 1.25 3.6 1 2.4 3.11 2 5.59 0.089 0.089 5.601 3.467 2.045 OK Fails Fails1 1.8 1.6 1.25 3.6 1 2.6 3.31 2 5.95 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails1 1.8 1.6 1.25 3.6 1 2.8 3.51 2 6.31 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails1 1.8 1.6 1.25 3.6 1 3 3.71 2 6.67 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails1 1.8 1.6 1.25 3.6 1 3.2 3.91 2 7.03 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails

1.5 1.8 1.6 1.25 5.4 1 1.2 1.91 2 5.15 0.089 0.089 5.601 3.467 2.045 OK Fails Fails1.5 1.8 1.6 1.25 5.4 1 1.4 2.11 2 5.69 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 1.6 2.31 2 6.23 0.089 0.089 5.601 3.467 2.045 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 1.8 2.51 2 6.77 0.114 0.114 7.201 4.458 2.629 OK Fails Fails1.5 1.8 1.6 1.25 5.4 1 2 2.71 2 7.31 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 2.2 2.91 2 7.85 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 2.4 3.11 2 8.39 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 2.6 3.31 2 8.93 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 2.8 3.51 2 9.47 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 3 3.71 2 10.01 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails1.5 1.8 1.6 1.25 5.4 1 3.2 3.91 2 10.55 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails

2 1.8 1.6 1.25 7.2 1 1.2 1.91 2 6.87 0.114 0.114 7.201 4.458 2.629 OK Fails Fails2 1.8 1.6 1.25 7.2 1 1.4 2.11 2 7.59 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 1.6 2.31 2 8.31 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 1.8 2.51 2 9.03 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 2 2.71 2 9.75 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 2.2 2.91 2 10.47 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 2.4 3.11 2 11.19 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 2.6 3.31 2 11.91 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 2.8 3.51 2 12.63 0.114 0.114 7.201 4.458 2.629 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 3 3.71 2 13.35 0.140 0.140 8.801 5.448 3.213 Fails Fails Fails2 1.8 1.6 1.25 7.2 1 3.2 3.91 2 14.07 0.140 0.140 8.801 5.448 3.213 Fails Fails Fails

Number of "OK" foundations: 40 20%Number of "Failed" foundations: 158 80%

Ground resistance moment, Mg Ground resistance moment, Mg

FLINT & NEILL PARTNERSHIP Page 1 of 1 Planting depths

Client: PB Planted Foundations for Traffic Signs

Assessment of Rules in PD6547

Job 970/314/03/2005

EJR

Addition to diameter to account for augered hole: 0.1 m

Sign Drag Wind FOS Wind Planting Height to Lever No. of Moment Post EffectiveArea Factor Pressure Load Depth Centre of Arm Posts about Dia Dia Good Average Poor Good Average Poor(m2) (kPa) (kN) (m) Sign (m) fulcrum (m) Dia (630) (390) (230) (630) (390) (230)

(m) (kNm) (m)

0.25 1.8 1.6 1.25 0.9 1 1.2 1.91 1 1.72 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.4 2.11 1 1.90 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.6 2.31 1 2.08 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.8 2.51 1 2.26 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2 2.71 1 2.44 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.2 2.91 1 2.62 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.4 3.11 1 2.80 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.6 3.31 1 2.98 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.8 3.51 1 3.16 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 3 3.71 1 3.34 0.076 0.176 11.088 6.864 4.048 OK OK OK0.25 1.8 1.6 1.25 0.9 1 3.2 3.91 1 3.52 0.076 0.176 11.088 6.864 4.048 OK OK OK

0.5 1.8 1.6 1.25 1.8 1 1.2 1.91 1 3.43 0.076 0.176 11.088 6.864 4.048 OK OK OK0.5 1.8 1.6 1.25 1.8 1 1.4 2.11 1 3.79 0.076 0.176 11.088 6.864 4.048 OK OK OK0.5 1.8 1.6 1.25 1.8 1 1.6 2.31 1 4.15 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 1.8 2.51 1 4.51 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 2 2.71 1 4.87 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 2.2 2.91 1 5.23 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 2.4 3.11 1 5.59 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 2.6 3.31 1 5.95 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 2.8 3.51 1 6.31 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 3 3.71 1 6.67 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 3.2 3.91 1 7.03 0.089 0.189 11.901 7.367 4.345 OK OK Fails

0.8 1.8 1.6 1.25 2.88 1 1.2 1.91 1 5.49 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 1.4 2.11 1 6.07 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 1.6 2.31 1 6.64 0.076 0.176 11.088 6.864 4.048 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 1.8 2.51 2 3.61 0.076 0.176 11.088 6.864 4.048 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2 2.71 2 3.90 0.076 0.176 11.088 6.864 4.048 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2.2 2.91 2 4.19 0.089 0.189 11.901 7.367 4.345 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2.4 3.11 2 4.47 0.089 0.189 11.901 7.367 4.345 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 2.6 3.31 2 4.76 0.089 0.189 11.901 7.367 4.345 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 2.8 3.51 2 5.05 0.089 0.189 11.901 7.367 4.345 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 3 3.71 2 5.34 0.089 0.189 11.901 7.367 4.345 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 3.2 3.91 2 5.63 0.089 0.189 11.901 7.367 4.345 OK OK Fails

1 1.8 1.6 1.25 3.6 1 1.2 1.91 2 3.43 0.076 0.176 11.088 6.864 4.048 OK OK OK1 1.8 1.6 1.25 3.6 1 1.4 2.11 2 3.79 0.076 0.176 11.088 6.864 4.048 OK OK OK1 1.8 1.6 1.25 3.6 1 1.6 2.31 2 4.15 0.076 0.176 11.088 6.864 4.048 OK OK Fails1 1.8 1.6 1.25 3.6 1 1.8 2.51 2 4.51 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 2 2.71 2 4.87 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 2.2 2.91 2 5.23 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 2.4 3.11 2 5.59 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 2.6 3.31 2 5.95 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 2.8 3.51 2 6.31 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 3 3.71 2 6.67 0.089 0.189 11.901 7.367 4.345 OK OK Fails1 1.8 1.6 1.25 3.6 1 3.2 3.91 2 7.03 0.089 0.189 11.901 7.367 4.345 OK OK Fails

1.5 1.8 1.6 1.25 5.4 1 1.2 1.91 2 5.15 0.089 0.189 11.901 7.367 4.345 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 1.4 2.11 2 5.69 0.089 0.189 11.901 7.367 4.345 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 1.6 2.31 2 6.23 0.089 0.189 11.901 7.367 4.345 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 1.8 2.51 2 6.77 0.114 0.214 13.501 8.358 4.929 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2 2.71 2 7.31 0.114 0.214 13.501 8.358 4.929 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2.2 2.91 2 7.85 0.114 0.214 13.501 8.358 4.929 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2.4 3.11 2 8.39 0.114 0.214 13.501 8.358 4.929 OK Fails Fails1.5 1.8 1.6 1.25 5.4 1 2.6 3.31 2 8.93 0.114 0.214 13.501 8.358 4.929 OK Fails Fails1.5 1.8 1.6 1.25 5.4 1 2.8 3.51 2 9.47 0.114 0.214 13.501 8.358 4.929 OK Fails Fails1.5 1.8 1.6 1.25 5.4 1 3 3.71 2 10.01 0.114 0.214 13.501 8.358 4.929 OK Fails Fails1.5 1.8 1.6 1.25 5.4 1 3.2 3.91 2 10.55 0.114 0.214 13.501 8.358 4.929 OK Fails Fails

2 1.8 1.6 1.25 7.2 1 1.2 1.91 2 6.87 0.114 0.214 13.501 8.358 4.929 OK OK Fails2 1.8 1.6 1.25 7.2 1 1.4 2.11 2 7.59 0.114 0.214 13.501 8.358 4.929 OK OK Fails2 1.8 1.6 1.25 7.2 1 1.6 2.31 2 8.31 0.114 0.214 13.501 8.358 4.929 OK OK Fails2 1.8 1.6 1.25 7.2 1 1.8 2.51 2 9.03 0.114 0.214 13.501 8.358 4.929 OK Fails Fails2 1.8 1.6 1.25 7.2 1 2 2.71 2 9.75 0.114 0.214 13.501 8.358 4.929 OK Fails Fails2 1.8 1.6 1.25 7.2 1 2.2 2.91 2 10.47 0.114 0.214 13.501 8.358 4.929 OK Fails Fails2 1.8 1.6 1.25 7.2 1 2.4 3.11 2 11.19 0.114 0.214 13.501 8.358 4.929 OK Fails Fails2 1.8 1.6 1.25 7.2 1 2.6 3.31 2 11.91 0.114 0.214 13.501 8.358 4.929 OK Fails Fails2 1.8 1.6 1.25 7.2 1 2.8 3.51 2 12.63 0.114 0.214 13.501 8.358 4.929 OK Fails Fails2 1.8 1.6 1.25 7.2 1 3 3.71 2 13.35 0.140 0.240 15.101 9.348 5.513 OK Fails Fails2 1.8 1.6 1.25 7.2 1 3.2 3.91 2 14.07 0.140 0.240 15.101 9.348 5.513 OK Fails Fails

Number of "OK" foundations: 137 69%Number of "Failed" foundations: 61 31%

Ground resistance moment, Mg Ground resistance moment, Mg

FLINT & NEILL PARTNERSHIP Page 1 of 1 Planting depths

Client: PB Planted Foundations for Traffic Signs

Assessment of Rules in PD6547

Job 970/314/03/2005

EJR

Addition to diameter to account for augered hole: 0.2 m

Sign Drag Wind FOS Wind Planting Height to Lever No. of Moment Post EffectiveArea Factor Pressure Load Depth Centre of Arm Posts about Dia Dia Good Average Poor Good Average Poor(m2) (kPa) (kN) (m) Sign (m) fulcrum (m) Dia (630) (390) (230) (630) (390) (230)

(m) (kNm) (m)

0.25 1.8 1.6 1.25 0.9 1 1.2 1.91 1 1.72 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.4 2.11 1 1.90 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.6 2.31 1 2.08 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 1.8 2.51 1 2.26 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2 2.71 1 2.44 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.2 2.91 1 2.62 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.4 3.11 1 2.80 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.6 3.31 1 2.98 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 2.8 3.51 1 3.16 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 3 3.71 1 3.34 0.076 0.276 17.388 10.764 6.348 OK OK OK0.25 1.8 1.6 1.25 0.9 1 3.2 3.91 1 3.52 0.076 0.276 17.388 10.764 6.348 OK OK OK

0.5 1.8 1.6 1.25 1.8 1 1.2 1.91 1 3.43 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 1.4 2.11 1 3.79 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 1.6 2.31 1 4.15 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 1.8 2.51 1 4.51 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 2 2.71 1 4.87 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 2.2 2.91 1 5.23 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 2.4 3.11 1 5.59 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 2.6 3.31 1 5.95 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 2.8 3.51 1 6.31 0.076 0.276 17.388 10.764 6.348 OK OK OK0.5 1.8 1.6 1.25 1.8 1 3 3.71 1 6.67 0.076 0.276 17.388 10.764 6.348 OK OK Fails0.5 1.8 1.6 1.25 1.8 1 3.2 3.91 1 7.03 0.089 0.289 18.201 11.267 6.645 OK OK Fails

0.8 1.8 1.6 1.25 2.88 1 1.2 1.91 1 5.49 0.076 0.276 17.388 10.764 6.348 OK OK OK0.8 1.8 1.6 1.25 2.88 1 1.4 2.11 1 6.07 0.076 0.276 17.388 10.764 6.348 OK OK OK0.8 1.8 1.6 1.25 2.88 1 1.6 2.31 1 6.64 0.076 0.276 17.388 10.764 6.348 OK OK Fails0.8 1.8 1.6 1.25 2.88 1 1.8 2.51 2 3.61 0.076 0.276 17.388 10.764 6.348 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2 2.71 2 3.90 0.076 0.276 17.388 10.764 6.348 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2.2 2.91 2 4.19 0.089 0.289 18.201 11.267 6.645 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2.4 3.11 2 4.47 0.089 0.289 18.201 11.267 6.645 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2.6 3.31 2 4.76 0.089 0.289 18.201 11.267 6.645 OK OK OK0.8 1.8 1.6 1.25 2.88 1 2.8 3.51 2 5.05 0.089 0.289 18.201 11.267 6.645 OK OK OK0.8 1.8 1.6 1.25 2.88 1 3 3.71 2 5.34 0.089 0.289 18.201 11.267 6.645 OK OK OK0.8 1.8 1.6 1.25 2.88 1 3.2 3.91 2 5.63 0.089 0.289 18.201 11.267 6.645 OK OK OK

1 1.8 1.6 1.25 3.6 1 1.2 1.91 2 3.43 0.076 0.276 17.388 10.764 6.348 OK OK OK1 1.8 1.6 1.25 3.6 1 1.4 2.11 2 3.79 0.076 0.276 17.388 10.764 6.348 OK OK OK1 1.8 1.6 1.25 3.6 1 1.6 2.31 2 4.15 0.076 0.276 17.388 10.764 6.348 OK OK OK1 1.8 1.6 1.25 3.6 1 1.8 2.51 2 4.51 0.089 0.289 18.201 11.267 6.645 OK OK OK1 1.8 1.6 1.25 3.6 1 2 2.71 2 4.87 0.089 0.289 18.201 11.267 6.645 OK OK OK1 1.8 1.6 1.25 3.6 1 2.2 2.91 2 5.23 0.089 0.289 18.201 11.267 6.645 OK OK OK1 1.8 1.6 1.25 3.6 1 2.4 3.11 2 5.59 0.089 0.289 18.201 11.267 6.645 OK OK OK1 1.8 1.6 1.25 3.6 1 2.6 3.31 2 5.95 0.089 0.289 18.201 11.267 6.645 OK OK OK1 1.8 1.6 1.25 3.6 1 2.8 3.51 2 6.31 0.089 0.289 18.201 11.267 6.645 OK OK OK1 1.8 1.6 1.25 3.6 1 3 3.71 2 6.67 0.089 0.289 18.201 11.267 6.645 OK OK Fails1 1.8 1.6 1.25 3.6 1 3.2 3.91 2 7.03 0.089 0.289 18.201 11.267 6.645 OK OK Fails

1.5 1.8 1.6 1.25 5.4 1 1.2 1.91 2 5.15 0.089 0.289 18.201 11.267 6.645 OK OK OK1.5 1.8 1.6 1.25 5.4 1 1.4 2.11 2 5.69 0.089 0.289 18.201 11.267 6.645 OK OK OK1.5 1.8 1.6 1.25 5.4 1 1.6 2.31 2 6.23 0.089 0.289 18.201 11.267 6.645 OK OK OK1.5 1.8 1.6 1.25 5.4 1 1.8 2.51 2 6.77 0.114 0.314 19.801 12.258 7.229 OK OK OK1.5 1.8 1.6 1.25 5.4 1 2 2.71 2 7.31 0.114 0.314 19.801 12.258 7.229 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2.2 2.91 2 7.85 0.114 0.314 19.801 12.258 7.229 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2.4 3.11 2 8.39 0.114 0.314 19.801 12.258 7.229 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2.6 3.31 2 8.93 0.114 0.314 19.801 12.258 7.229 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 2.8 3.51 2 9.47 0.114 0.314 19.801 12.258 7.229 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 3 3.71 2 10.01 0.114 0.314 19.801 12.258 7.229 OK OK Fails1.5 1.8 1.6 1.25 5.4 1 3.2 3.91 2 10.55 0.114 0.314 19.801 12.258 7.229 OK OK Fails

2 1.8 1.6 1.25 7.2 1 1.2 1.91 2 6.87 0.114 0.314 19.801 12.258 7.229 OK OK OK2 1.8 1.6 1.25 7.2 1 1.4 2.11 2 7.59 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 1.6 2.31 2 8.31 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 1.8 2.51 2 9.03 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 2 2.71 2 9.75 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 2.2 2.91 2 10.47 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 2.4 3.11 2 11.19 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 2.6 3.31 2 11.91 0.114 0.314 19.801 12.258 7.229 OK OK Fails2 1.8 1.6 1.25 7.2 1 2.8 3.51 2 12.63 0.114 0.314 19.801 12.258 7.229 OK Fails Fails2 1.8 1.6 1.25 7.2 1 3 3.71 2 13.35 0.140 0.340 21.401 13.248 7.813 OK Fails Fails2 1.8 1.6 1.25 7.2 1 3.2 3.91 2 14.07 0.140 0.340 21.401 13.248 7.813 OK Fails Fails

Number of "OK" foundations: 173 87%Number of "Failed" foundations: 25 13%

Ground resistance moment, Mg Ground resistance moment, Mg

FLINT & NEILL PARTNERSHIP Page 1 of 1 Planting depths

Wind Loading fir Signs to BS EN 12899

ANNEX E

RECOMMENDATIONS FOR DRAFT NATIONAL ANNEX

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899

Wind Loading fir Signs to BS EN 12899

A review of the structural requirements of the UK National Annex to prEN 12899-1: 2005(E) has resulted in the following comments and recommendations: E.1 Partial Action Factor It is considered that the recommended class of PAF1 is appropriate for design of traffic signs in the UK. E.2 Wind Loads It is considered that:

All of the classes given in the National Annex should only apply up to a limiting altitude of 250m above mean sea level;

The classification given in the National Annex for England is satisfactory, with the exception of the Isle of Man, where Class WL8 should apply;

The classification given in the National Annex for Northern Ireland should be WL9; and The classification given in the National Annex for Scotland should be WL9, subject to the

exceptions given in Section 3.1 of this report. Refer to Section 3.8.3. for further details. E.3 Dynamic Snow Loads The recommendations for dynamic loads for snow clearance given in the National Annex are based on the use of snow blowers. Instead, it is recommended that design criteria are based on the following factors:

The likely occurrence of snow requiring clearance; and Whether clearance will be required in the event of significant snow fall (e.g. if the road is an

important transport link). Recommendations for load classes are given where it is decided that design for dynamic snow loads is required; refer to Section 3.4.3. E.4 Temporary Deflections The recommendations for temporary deflections given in the National Annex match those given in Section 3.3 of this report.

Implementation of Eurocodes Wind Loading for Siigns to BE EN 12899