simply supported primary composite beam

17
Document Ref: SX015a-EN-EU Sheet 1 of 16 Title CALCULATION SHEET Example: Simply supported primary composite beam Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005 Checked by Alain BUREAU Date August 2005 Example: Simply supported primary composite beam This worked example deals with a simply supported composite beam. Two secondary beams are connected to this primary beam. 6,0 m 6,0 m 9,0 m 3,0 m 3,0 m The secondary beams are represented by two concentrated loads : 1 1 1 1 1 : Lateral restraints at the construction stage Example: Simply supported primary composite beam Created on Wednesday, February 08, 2012 This material is copyright - all rights reserved. Use of this document is subject to the terms and conditions of the Access Steel Licence Agreement

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Page 1: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 1 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Example: Simply supported primary composite beam This worked example deals with a simply supported composite beam. Two secondary beams are connected to this primary beam.

6,0 m

6,0 m

9,0 m

3,0 m 3,0 m

The secondary beams are represented by two concentrated loads :

1 1

1 1 1 : Lateral restraints at the construction stage

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Page 2: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 2 of 16 Title

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

CALCULATION SHEET

Checked by Alain BUREAU Date August 2005

The beam is a I-rolled profile in bending about the strong axis. This example includes :

- the classification of the cross-section,

- the calculation of the effective width of the concrete flange,

- the calculation of the shear resistance of a headed stud,

- the calculation of the degree of shear connection,

- the calculation of the bending resistance,

- the calculation of the shear resistance,

- the calculation of the longitudinal shear resistance of the slab,

- the calculation of the deflection at serviceability limit state.

This example does not include any shear buckling verification of the web.

Partial factors

• γG = 1,35 (permanent loads)

• γQ = 1,50 (variable loads)

• γM0 = 1,0

• γM1 = 1,0

• γV = 1,25

• γC = 1,5

EN 1990

EN 1993-1-1

§ 6.1 (1)

EN 1994-1-1

§ 6.6.3.1

EN 1992-1-1

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Page 3: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 3 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Basic data Design a composite beam of a multi-storey building according to the data given below. The supporting beams are not propped. The profiled steel sheeting is parallel to the primary beam.

• Span length : 9,00 m

• Bay width : 6,00 m

• Slab depth : 14 cm

• Partitions : 0,75 kN/m2

• Secondary beams (IPE 270) : 0,354 kN/m

• Imposed load : 2,50 kN/m2

• Construction load : 0,75 kN/m2

• Reinforced concrete density : 25 kN/m3

Try IPE 400 – Steel grade S355

Depth ha = 400 mm

Width b = 180 mm

Web thickness tw = 8,6 mm

Flange thickness tf = 13,5 mm

Fillet r = 21 mm

Mass 66,3 kg/m

z

z

y y

tf

tw

b

ha

Euronorm

19-57

Section area Aa = 84,46 cm2

Second moment of area /yy Iy = 23130 cm4

Elastic section modulus /yy Wel,y = 1156 cm3

Plastic section modulus /yy Wpl.y = 1307 cm3

Radius of gyration /zz iz = 3,95 cm

Modulus of elasticity of steel Ea = 210 000 N/mm2

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Page 4: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 4 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Profiled steel sheeting Thickness of sheet t = 0,75 mm

Slab depth h = 140 mm

Overall depth of the profiled steel sheeting excluding embossments

hp = 58 mm

b1 = 62 mm b2 = 101 mm e = 207 mm

Connectors Diameter d = 19 mm

Overall nominal height hsc = 100 mm

Ultimate tensile strength fu = 450 N/mm2

Number of studs n = 74, 1 row

(Stud at beam mid-span ignored)

0,5hp

hp

hsc

h

b0

b1 b2

e

Concrete class : C 25/30 Value of the compressive strength at 28 days fck = 25 N/mm2

Secant modulus of elasticity of concrete Ecm = 31 000 N/mm2

EN 1992-1-1

§ 3.1.3

Table 3.1

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Page 5: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 5 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Permanent load : To take into account the troughs of the profiled steel sheeting , the weight of the slab for the secondary beams is taken as:

25 × 3,0 × (0,14 – 2

145,0106,0 + ×207,0058,0 ) = 7,86 kN/m

Concentrated loads during the construction stage :

FG = (0,354 + 7,86) × 6,0 = 49,28 kN

Permanent loads in the final stage :

So, the value of the concentrated loads on the primary beam is:

FG = (0,354 + 7,86 + 0,75 × 3,0) × 6,0 = 62,78 kN

Self weight of the primary beam :

qG = 9,81 × 66,3 × 10-3 = 0,65 kN/m

Variable load (Imposed load) : Concentrated loads during the construction stage :

FQ = 0,75 × 3,0 × 6,0 = 13,5 kN

Concentrated loads in the final stage:

FQ = 2,5 × 3,0 × 6,0 = 45,0 kN

ULS Combination :

γG FG + γQ FQ = 1,35 × 62,78 + 1,50 ×45,0 = 152,25 kN

γG qG + γQ qQ = 1,35 × 0,65 = 0,877 kN/m

Eq. (6.10) is used. In some countries, the National Annex may specify the use of equations (6.10a) and (6.10b).

EN 1990

§ 6.4.3.2

ULS Combination during the construction stage:

γG FG + γQ FQ = 1,35 × 49,28 + 1,50 ×13,5 = 86,78 kN

γG qG + γQ qQ = 1,35 × 0,65 = 0,877 kN/m

Example: Simply supported primary composite beamC

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Page 6: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 6 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Moment diagram

465,6 kNm

M

Maximum moment at mid span :

My,Ed = 3,0 × 152,25 + 0,125 × 0,877 × 9,02 = 465,6 kNm

Maximum moment at mid span (sequence of construction) :

My,Ed = 3,0 × 86,78 + 0,125 × 0,877 × 9,02 = 269,2 kNm

Shear force diagram

V

156,20 kN

Maximum shear force at supports :

Vz,Ed = 152,25 + 0,5 × 0,877 × 9,0 = 156,20 kN

Maximum shear force at supports (sequence of construction) :

Vz,Ed = 86,78 + 0,5 × 0,877 × 9,0 = 90,73 kN

Yield strength Steel grade S355

The maximum thickness is 13,5 mm < 40 mm, so : fy = 355 N/mm2

Note : The National Annex may impose either the values of fy from the Table 3.1 or the values from the product standard. Does not matter in this case.

EN 1993-1-1

Table 3.1

Section classification :

The parameter ε is derived from the yield strength : 0,81 ][N/mm

235 2y

==f

ε

Note : The classification is made for the non composite beam. For the composite beam the classification is more favourable for the web.

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Page 7: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 7 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Outstand flange : flange under uniform compression

c = (b – tw – 2 r) / 2 = (180 – 8,6 – 2 × 21)/2 = 64,7 mm

c/tf = 64,7 / 13,5 = 4,79 ≤ 9 ε = 7,29 Class 1

EN 1993-1-1

Table 5.2

(sheet 2 of 3)

Internal compression part :

c = ha – 2 tf – 2 r = 400 – 2 × 13,5 – 2 × 21 = 331 mm

c / tw = 331 / 8,6 = 38,5 < 72 ε = 58,3 Class 1

The class of the cross-section is the highest class (i.e. the least favourable) between the flange and the web, here : Class 1

So the ULS verifications should be based on the plastic resistance of the cross-section.

EN 1993-1-1

Table 5.2

(sheet 1 of 3)

Construction stage

Moment resistance The design resistance for bending of a cross section is given by :

Mc,Rd = Mpl,Rd = Wpl,y fy / γM0 = (1307 × 355 / 1,0) / 1000

Mc.Rd = 463,98 kNm

My,Ed / Mc,Rd = 269,2 / 463,98 = 0,58 < 1 OK

EN 1993-1-1

§ 6.2.5

Reduction factor for lateral torsional buckling To determine the design buckling resistance moment of a laterally unrestrained beam, the reduction factor for lateral torsional buckling must be determined. The restraint provided by the steel sheet is in this case quite small and it is neglected. The following calculation determines this factor by a simplified method for lateral torsional buckling. This method avoids calculating the elastic critical moment for lateral torsional buckling.

Non-dimensional slenderness

The non-dimensional slenderness may be obtained from the simplified method for steel grade S355:

0,853 89

300/3,95 89/ z

LT ===iLλ

See NCCI

SN002

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Page 8: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 8 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

For rolled profiles, 0,4 LT,0 =λ

Note : The value of LT,0λ may be given in the National Annex. The recommended value is 0,4.

So LT,0LT 0,853 λλ >= =0,4

EN 1993-1-1

§ 6.3.2.3(1)

Reduction factor For rolled sections, the reduction factor for lateral torsional buckling is calculated from :

⎪⎩

⎪⎨⎧

−+=

2LT

LT

LT

2LT

2LTLT

LT 1

1.0 but

1 λ

χ

χ

λβφφχ

where : ( )[ ] 1 0,5 LTLT,0LTLTLT

2λβλλαφ +−+=

EN 1993-1-1

§ 6.3.2.3 (1)

αLT is the imperfection factor for LTB. When applying the method for rolled profiles, the LTB curve has to be selected from the table 6.5 :

For ha/b = 400 / 180 = 2,22 > 2 Curve c (αLT = 0,49)

0,4 LT,0 =λ and β = 0,75

Note : The values of LT,0λ and β may be given in the National Annex. The recommended values are 0,4 and 0,75 respectively.

EN 1993-1-1

Table 6.5

Table 6.3

We obtain : ( )[ ] 0,884 (0,853)0,75 0,40,853 0,49 1 0,5 2LT =×+−+=φ

and : 0,730 (0,853)0,75(0,884) 0,884

1 22LT =

×−+=χ

Then, we check : χLT = 0,730 < 1,0

but : χLT = 0,730 < 2LT / 1 λ = 1,374

So : χLT = 0,730

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Page 9: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 9 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Design buckling resistance moment

Mb,Rd = χLT Wpl,y fy / γM1

Mb,Rd = (0,730 × 1307000 × 355 / 1,0) × 10-6 = 338,7 kNm

My,Ed / Mb,Rd = 269,2 / 338,7 = 0,795 < 1 OK

EN 1993-1-1

§ 6.3.2.1

Shear Resistance The shear plastic resistance depends on the shear area, which is given by:

Av,z = A – 2 b tf + (tw + 2 r) tf

Av,z = 8446 – 2 × 180 × 13,5 + (8,6 + 2 × 21) × 13,5 = 4269 mm2

EN 1993-1-1

§ 6.2.6 (3)

Shear plastic resistance

kN 874,97 1,0

10)3 / (3554269 )3 / (

3

M0

yzv,Rdz,pl, =

××==

γfA

V

Vz,Ed / Vpl,z,Rd = 90,73 / 874,97 = 0,104 < 1 OK

EN 1993-1-1

§6.2.6 (2)

Note that the verification to shear buckling is not required when :

hw / tw ≤ 72 ε / η

The relevant value of η is : η = 1,2

hw / tw = (400 – 2 × 13,5) / 8,6 = 43 < 72 × 0,81 / 1,2 = 48,6

EN 1993-1-1

§ 6.2.6 (6)

EN 1993-1-5

§ 5.1 (2)

Interaction between bending moment and shear force If Vz,Ed < Vpl,Rd / 2 then the shear force may be neglected.

So, Vz,Ed = 90,73 kN < Vpl,Rd / 2 = 874,97 / 2 = 437,50 kN OK

EN 1993-1-1

§ 6.2.8 (2)

Final stage

Effective width of concrete flange The effective width is constant between 0,25 L and 0,75 L, where L is the span length. From L/4 to the closest support, the effective width decreases linearly. The concentrated loads are located between 0,25 L and 0,75 L.

EN 1994-1-1

§ 5.4.1.2

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Page 10: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 10 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

The total effective width is determined by:

∑+=eff,1 ei0 bbb

b0 is the distance between the centres of the outstand shear connectors,

here b0 = 0 ;

bei is the value of the effective width of the concrete flange on each side of the web and taken as bei = Le / 8 but ≤ bi = 3,0 m

beff,1 = 0 + 9,0 / 8 = 1,125 m, then beff = 2 × 1,125 = 2,25 m < 3,0 m

(Figure 5.1)

Design shear resistance of a headed stud The shear resistance should be determined by :

290480

Min×=V

cm2

V

2u

lRd γα

γπ E fd ,

;/d f,

kP ck

hsc / d = 100 / 19 = 5,26 > 4, so α = 1

EN 1994-1-1

§ 6.6.3.1

Reduction factor (kl)

For sheeting with ribs transverse to the supporting beam, the reduction factor for shear resistance is calculated by :

⎟⎟⎠

⎞⎜⎜⎝

⎛−= 16,0

p

sc

p

0l h

hhbk but ≤ 1

EN 1994-1-1

§ 6.6.4.1

Where : nr = 1

hp = 58 mm

hsc = 100 mm

b0 = 82 mm

So, 6140158

100588260l ,,k =⎟

⎠⎞

⎜⎝⎛ −= ≤ 1 OK

25131000×2519×1×290

251419××450×80

Min×6140=22

Rd , ,

;,

/ ,,P

π 3.10−

( )kN7373kN6681Min×6140= ,;,,

PRd = 45,27 kN

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Page 11: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 11 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Degree of shear connection The degree of shear connection is defined by :

fc,

c

NN

Where : Nc is the design value of the compressive normal force in the concrete flange

Nc,f is the design value of the compressive normal force in the concrete flange with full shear connection

EN 1994-1-1

§ 6.2.1.3 (3)

At the load location:

The compressive normal force in the concrete flange represents the force for full connection.

Ac is the cross-sectional area of concrete, so at the load location: Ac = beff hc

with hc = h - hp = 140 – 58 = 82 mm

Ac = 2250 × 82 = 184500 mm2

So, =1051

25×184500×850=850=850= 3

C

ckccdcfc, ,

,f

A,fA,Nγ

2614 kN

Since the maximum moment is nearly reached at the load location, the studs should be placed between the support and the concentrated load. However studs should also be placed between the concentrated loads.

e2

e1

3,0 m 1,5 m

31 studs spaced at e1 = 95 mm and 6 studs spaced at e2 = 220 mm

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Page 12: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 12 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

So, the resistance of the shear connectors limits the normal force to not more than:

1403 KN =2745×31=×= Rdc ,PnN

So, 5370=26141403

==fc,

c ,NN

η

The ratio η is less than 1,0 so the connection is partial.

Verification of bending resistance

Minimum degree of shear connection The minimum degree of shear connection for a steel section with equal flanges is given by :

( eL,-,f

030750355-1 y

min ⎟⎟⎠

⎞⎜⎜⎝

⎛=η ) with Le ≤ 25

EN 1994-1-1

§ 6.6.1.2

Le is the distance in sagging bending between points of zero bending moment in metres, for our example : Le = 9,0 m

So, ηmin = 1 – (355 / 355) (0,75 – 0,03 × 9,0) = 0,520

Then, ηmin = 0,520 < η = 0,537 OK

Plastic Resistance Moment at the load location

The design value of the normal force in the structural steel section is given by :

2998 kN =0110×355×8446== 3M0yaapl, ,/ /fAN γ

So, =2614×5370=×=> fc,capl, ,NNN η 1403 kN

EN 1994-1-1

§ 6.2.1.2 and

§ 6.2.1.3

With the ductile shear connectors and the cross-section of the steel beam in Class 1, the resistance moment of the critical cross-section of the beam MRd at the load location is calculated by means of rigid-plastic theory except that a reduced value of the compressive force in the concrete flange Nc is used in place of the force Ncf.

Here, the plastic stress distribution is given below:

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Page 13: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 13 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

MRd

+

- Nc=η Nc,f= 1403 kN

Na= 2201 kN hn

hp 797 kN

The position of the plastic neutral axis is : hn = 388 mm

Then the design bending resistance of the composite cross-section is :

MRd = 738 kNm

So, My,Ed / MRd = 465,6 / 738 = 0,63 < 1 OK

Shear Resistance The shear plastic resistance is the same as for steel beam alone.

So, kN 97,874 = Rdz,pl,V

Vz,Ed / Vpl,z,Rd = 156,20 / 874,97 = 0,18 < 1 OK

EN 1994-1-1

§ 6.2.2.2

Interaction between bending moment and shear force If Vz,Ed < Vpl,Rd / 2 then the shear force may be neglected.

So, Vz,Ed = 156,20 kN < Vpl,Rd / 2 = 874,97 / 2 = 437,50 kN OK

EN 1993-1-1

§ 6.2.8 (2)

Longitudinal Shear Resistance of the Slab The plastic longitudinal shear stresses is given by :

xh

FvΔ

Δ=

f

dEd

Where Δx = 9,0 / 2 = 4,5 m

EN 1992-1-1

§ 6.2.4

(Figure 6.7)

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Page 14: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 14 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

The value for Δx is half the distance between the section where the moment is zero and the section where the moment is a maximum, and we have two areas for the shear resistance.

ΔFd = Nc / 2 = 1403 / 2 = 701,5 kN

hf = h - hp = 140 – 58 = 82 mm

=4500×82

10×5701==

3

f

d ,xh

FvEd Δ

Δ1,9 N/mm2

To prevent crushing of the compression struts in the concrete flange, the following condition should be satisfied :

ffcdEd cossin θθν fv < with [ ]250/16,0 ckf−=ν and θf = 45 °

5,45,05,1

252502516,0Ed =××⎥⎦

⎤⎢⎣⎡ −×<v N/mm2 OK

The following inequality should be satisfied for the transverse reinforcement :

Asf fyd / sf ≥ vEd hf / cot θf where fyd = 500 / 1,15 = 435 N/mm2

Assume the spacing of the bars sf = 200 mm and there is no contribution from the profiled steel sheeting

Asf ≥ =01×435200×82×91,

,71,6 mm2

We can take 10 mm diameter bars (78,5 mm2) at 200 mm cross-centres could be used for this design.

Serviceability Limit State verifications

Formula for the calculation of the deflection due to G + Q :

Qy

22

Q

Gy

22

y

4G

G

24)4(3w

24)4(3

384 5

FIE

aLa

FIE

aLaIE

Lqw

−×=

−×+=

So, w = wG + wQ

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Page 15: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 15 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Construction stage

SLS Combination during the construction stage : FG + FQ = 49,28 + 13,5 = 62,78 kN

qG = 0,65 kN/m

EN 1990

§ 6.5.3

Deflection during the construction stage : Iy is the second moment of area of the steel beam.

492801023130 210000 24

)30004-90003(30001023130210000 384

900065,0 5 4

22

4

4

G ××××

×××+

×××××

=w

mm 3,272,261,1 G =+=w

mm 7,2135001023130 210000 24

)30004-90003(3000w 4

22

Q =××××

×××=

So, w = wG + wQ = 27,3 + 7,2 = 34,5 mm

The deflection under (G+Q) is L/261

Final stage

SLS Combination

FG + FQ = 62,78 + 45,0 = 107,78 kN

qG = 0,65 kN/m

EN 1990

§ 6.5.3

Deflection at the final stage : Iy depends on the modular ratio (n) depending on the type of loading. By simplification, we can take :

n0 = Ea / Ecm = 210000 / 31000 = 6,77 for short-term effects (Q)

So Iy = 82458 cm4 at mid span

And n = 3Ea / Ecm = 20,31 for permanent loads (G)

So Iy = 62919 cm4

EN 1994-1-1

§ 7.2.1

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Page 16: Simply Supported Primary Composite Beam

Document Ref: SX015a-EN-EU Sheet 16 of 16 Title

CALCULATION SHEET

Example: Simply supported primary composite beam

Eurocode Ref EN 1993-1-1, EN 1994-1-1 Made by Arnaud LEMAIRE Date August 2005

Checked by Alain BUREAU Date August 2005

Note : It may be used for both short-term and long-term loading, a nominal modular ratio (n) corresponding to an effective modulus of elasticity for concrete Ec,eff taken as Ecm / 2.

EN 1994-1-1

§ 5.4.2.2 (11)

wG = 27,3 mm

13500×10×62919×210000×24

3000×4-9000×3×3000= 4

2

partitions )(

w2

= 2,6 mm

45000×10×82458×210000×24

3000×4-9000×3×3000= 4

2

)(

w2

Q = 6,7 mm

So, w = wG + wpartitions + wQ = 27,3 + 2,6 + 6,7 = 36,6 mm

The deflection under (G + Q) is L/246

Note 1 : The limits of deflection should be specified by the client. The National Annex may specify some limits. Here the result may be considered as fully satisfactory.

Note 2 : Concerning vibrations, the National Annex may specify limits concerning the frequency. Here the total deflection is low and the mass fairly high and by experience there is no problem of vibration.

EN 1993-1-1

§ 7.2.3

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Page 17: Simply Supported Primary Composite Beam

Example: Simply supported primary composite beam SX015a-EN-EU.doc

Quality Record

RESOURCE TITLE Example: Simply supported primary composite beam

Reference(s)

ORIGINAL DOCUMENT

Name Company Date

Created by Arnaud LEMAIRE CTICM 29/08/05

Technical content checked by Alain BUREAU CTICM 29/08/05

Editorial content checked by

Technical content endorsed by the following STEEL Partners:

1. UK G W Owens SCI 11/1/06

2. France A Bureau CTICM 11/1/06

3. Sweden A Olsson SBI 11/1/06

4. Germany C Müller RWTH 11/1/06

5. Spain J Chica Labein 11/1/06

Resource approved by Technical Coordinator

G W Owens SCI 09/06/06

TRANSLATED DOCUMENT

This Translation made and checked by:

Translated resource approved by:

Example: Simply supported primary composite beamC

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