classification of piles-secured

PILE TYPES AND DESCRIPTIONS

ABSTRACT This document presents a description of different

types of foundation piles along with a brief summary

and the uses of each type of pile

Arvand MH Navabi Advanced Foundation Design

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PILE TYPES AND DESCRIPTIONS ARVAND M.H. NAVABI M.S. FALL 2016

Table of Contents PREFACE: CONCEPT OF PILES ................................................................................................................................. 2

CLASSIFICATION OF PILES ...................................................................................................................................... 3

CLASSIFICATION OF PILES WITH RESPECT TO THEIR INSTALMENT TECHNIQUES .............................................................................. 4 Driven Piles ............................................................................................................................................................ 4 Drilled Shaft .......................................................................................................................................................... 5

CLASSIFICATION OF PILES BY TYPE....................................................................................................................................... 6 Timber Piles ........................................................................................................................................................... 6 Steel Piles .............................................................................................................................................................. 7

Steel H-piles........................................................................................................................................................................ 8 Open End Steel Pipe Piles ................................................................................................................................................. 11 Closed End Steel Pipe Piles ............................................................................................................................................... 13 Conical Steel Pipe Pile ...................................................................................................................................................... 14 Monotube and Tapertube Pile ......................................................................................................................................... 15

Concrete piles ...................................................................................................................................................... 16 Pre-stressed Concrete Piles .............................................................................................................................................. 17

Concrete pile splicing................................................................................................................................................... 19 Precast .............................................................................................................................................................................. 21 Cast in situ ........................................................................................................................................................................ 23 Under-Reamed Piles ......................................................................................................................................................... 24 Augercast Pile ................................................................................................................................................................... 26 Franki Piles ....................................................................................................................................................................... 27

Composite Piles ................................................................................................................................................... 28 Other Piles ........................................................................................................................................................... 29

Vibro replacement (Stone Columns) ................................................................................................................................ 29 Micropiles ......................................................................................................................................................................... 29

SUMMARY ........................................................................................................................................................... 31

TIMBER PILES .............................................................................................................................................................. 31 H-PILES ...................................................................................................................................................................... 32 OPEN END PIPE PILE ..................................................................................................................................................... 33 CLOSED END PIPE PILE .................................................................................................................................................. 34 MONOTUBE PILE .......................................................................................................................................................... 35 PRE-STRESSED CONCRETE .............................................................................................................................................. 36 CYLINDER PILES ............................................................................................................................................................ 36 COMPOSITE PILE .......................................................................................................................................................... 37

TABLES ................................................................................................................................................................. 39

FIGURES ............................................................................................................................................................... 40

REFERENCES ......................................................................................................................................................... 42

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Preface: Concept of Piles Piles are generally associated with difficult foundation conditions and weak sub-surface soils. Piles

transmit forces from the superstructure to a lower stratum that has sufficient bearing value to support

the completed structures and all applied loads (see Figure 1 and 2). End-bearing piles primarily transfer

loads through the tip. Friction piles primarily transfer loads through tangential skin friction.

Figure 1. End Bearing and Friction Force against the Super Structure Load

Figure 2. Transfer of load to piles are shown in this Figure.

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Classification of piles Piles might be either wood, concrete, reinforced concrete or steel. In this section different types of piles

are described after categorizing piles into two types, driven piles and drilled shafts. Driven pile

classification is also shown in figure 3.

Figure 3. General classification of load bearing piles.

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Figure 5. A schematic of pile driving procedure (HaywardBaker, 2015).

Figure 4. A pile driving rig while driving a pile (HaywardBaker, 2015)

Classification of piles with respect to their instalment techniques

Driven Piles Driven piles are deep foundation elements driven to a design depth or resistance. If penetration of dense

soil is required, predrilling may be required for the pile to penetrate to the design depth. Types include

timber, pre-cast concrete, steel H-piles, and pipe piles. The finished foundation element resists

compressive, uplift and lateral loads. The technique has been used to support buildings, tanks, towers and

bridges. Driven piles can also be used to provide lateral support for earth retention walls. Steel sheet piles

and soldier piles are the most common type of driven piles for this application (HaywardBaker, 2015).

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Figure 7. Drilled shafts for the Wangum Road Bridge replacement in Moira, NY (HaywardBaker, 2015).

Figure 6. Schematic of an Auger Rig drilling a hole in which it will later be filled with reinforcements and concrete (HaywardBaker, 2015).

Drilled Shaft Drilled shafts, are typically high-capacity cast-in-place deep foundation elements constructed using an

auger. A hole having the design diameter of planned shaft is first drilled to the design depth. If the hole

requires assistance to remain open, casing or drilling fluid is used.

Full-length reinforcing steel is then lowered into the hole and the hole is filled with concrete. The finished

foundation element resists compressive, uplift and lateral loads. The technique has been used to support

buildings, tanks, towers and bridges.

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Classification of piles by type In this section piles are categorized by the five more commonly used material, Timber, Steel (H-piles or

pipe piles), concert piles and composite piles, figure 6.

Figure 8. Classification of piles with respect to their material.

Timber Piles Historically, timber has been used for pile foundation for centuries and this is because of availability and

affordability of timber piles in comparison to steel and concrete piles, although for heavier loads timber

is not a suitable foundation option. One of the main issues on timber is their vulnerability to rotting above

groundwater level, but in comparison to other pile solutions, timber has relatively high durability towards

rotting beneath the water table, this is due to the lack of dissolved oxygen in water. To ensure timber

durability above water level, wood is treated with numerous preservatives. Timber piles are considered

driven piles and their usual use are in small low cost bridges and minor infrastructures, but mostly in ports

and harbors, marine and raised coastal construction (Hanning, 2013).

Table 1 provides a brief description of timber pile specifications.

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Table 1. Timber Pile Specifications (Hanning, 2013).

Pile Type: Timber Specifications And Details

Typical Lengths 15 to 75 ft.-Southern Pile 15 to 120 ft.-Douglas Fir1

Material Specifications ASTM D-25

Maximum Stresses Typical Design Stress: 0.81 to 1.2 ksi Driving Stress: 3 Times The Design Stress

Design Loads 10 to 55 tons

Advantages Comparatively low initial cost. Easy to handle. Resistance to decay if permanently submerged.

Disadvantages Vulnerable to decay if untreated and intermittently submerged. Vulnerable to damage at pile head and pile toe in hard driving. Difficult to splice.

Remarks Best suited for friction pile in granular soil

Figure 9. Timber Piles driven to the soil, Timber piles are usually suitable for granular soil.

Steel Piles Steel piles, like timber, are driven by percussion means and have a variety of suitable cross-sections. In

addition to the common sheet piles, the three main types are H sections, box piles and tube piles. Typical

sections are shown in Fig. 7.

The main use of steel piles is for temporary works, retaining walls and marine structures. The problem of

corrosion of the steel can be overcome by suitable protection. However, account should be taken of the

abrasion during driving on the final performance of such protection/coatings. In addition to coating,

1 Wood piles used splices to join multiple segments end-to-end when the driven depth was too long

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increased metal thickness and cathodic protection may be appropriate for particular locations and

conditions [2].

Figure 10. Types of common steel piles. From left to right, H-Piles, Box-Piles, Tube-Piles.

Steel H-piles Table 2. Steel H-Pile Specifications (Hanning, 2013).

Pile Type: H-Piles Specifications And Details

Typical Lengths 15 to 120 feet or greater

Material Specifications ASTM A-572, A-588, A-690

Maximum Stresses Typical Design Stress: 12.5 to 16.5 Driving Stress: 45 ksi

Design Loads Standard H section (8 to 14 inch): 66 to 284 tons Newer H sections (16 to 18 inch): 161 to 495 tons

Advantages Available in various sizes, sections and lengths. Easy to splice. High capacities possible. Low soil displacements. May penetrate larger obstructions with driving shoes.

Disadvantages Vulnerable to corrosion. Not recommended as friction pile in granular soil.

Remarks Best suited for toe bearing on rock.

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Figure 11. Driven H-Piles surrounded by Sheet Piles

Figure 12. A new type of H-Pile, the section is 18 inches, shown in the picture.

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Figure 13. An H-Pile splicer is shown in this figure. Splicers are used to extend the piles if needed

Table 3. This table provides detailed measures for different types of H-Piles

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Open End Steel Pipe Piles

Unplugged open-ended steel pipe pile

This pile is a steel pipe, which is open at both ends and is driven into the ground with blows to the top of

the pile. After the pile driving the ground level is approximately the same both inside and outside the

pile.

Plugged open-ended steel pipe pile

This pile is a steel pipe, which is open at both ends and is driven into the ground with blows to the top of

the pile. On completion of the pile driving the ground level is distinctly lower inside than outside the

pile. The state of plugging of the pile is determined on the basis of the difference between the ground

levels inside and outside the pile. Normally formation of the plug requires, that the pile penetrates into

the plugging soil layer not less than 10 ⋅ d length, where d is the diameter of the pile.

Table 4. Open End Pipe Pile Specifications (Hanning, 2013).

Pile Type: Open End Pipe Pile Specifications And Details


Material Specifications ASTM A-252, Grade 2 or 3 (Fy=35.0 or 45 ksi) ACI 318-for concrete (if filled)

Maximum Stresses Typical Design Stress: o.25 Fy to 0.33 Fy (on steel) Driving Stress: 0.90 Fy 31.5 to 40.5 ksi


Advantages Available in various lengths, diameters and wall thicknesses. Pile can be cleaned out and driven deeper. Easy to splice. Good resistant's to damage from pile driving operations. Can be installed with conventional equipment. High capacities possible. Low soil displacements.

Disadvantages Vulnerable to corrosion. When driven open ended pile can become plugged with soil requiring pile to drilled or "cleaned" out

Remarks High bending resistance on un supported length. Figure 14. Open End Pipe Piles, ASTM A-252 Steel.

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Figure 15. Driving procedure of Open End Pipe Piles.

Figure 16. Driving procedure of Open End Pipe Piles.

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Closed End Steel Pipe Piles

A wide range of sizes of steel tube (or pipe) is commonly available and Piling Contractors have

experience in driving tubes from 350 mm to 1500 mm diameter with wall thicknesses from 7 mm to 25

mm.

Closed end pipe piles have the bottom of the pile sealed with a steel plate or cast steel shoe. When

driving through hard strata pile toes may be reinforced with a secondary driving shoe to assist

penetration and minimize pile damage.

Table 5. Detailed specifications for Closed End Steel Pipe (Hanning, 2013).

Pile Type: Closed End Pipe Pile Specifications And Details





Advantages Available in various lengths, diameters and wall thicknesses. Easy to splice. Good resistant's to damage from pile driving operations. Can be installed with conventional equipment. High capacities possible.

Disadvantages Vulnerable to corrosion. Soil displacements and can result in soil heave.

Remarks High bending resistance where unsupported length is laterally loaded.

Figure 17. Closed End Pipe Pile

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Conical Steel Pipe Pile

End closure may be flat plates or conical points. Conical points have sixty degree configurations and are

available with either an inside flange or outside flange. This angle parts the soil and preserves friction

along the walls rather than just beating a path through it. Use of conical points keeps soil disturbance to

a minimum and permits development of maximum friction support. Where boulders or sloping rock are

encountered, they distribute the reaction stresses to the entire periphery of the pipe, rather than just a

segment. On boulders or uneven rock, the point distributes the hammer impact load around the

periphery of the pipe rather than concentrating it as occurs with a flat plate closure.

Conical points are also used as end-closures for pipe piles although they generally cost more than plate

type protection. Conical points should be cast steel meeting the requirements of ASTM a-27 65/35; for

tougher conditions A-148 80/40 is preferred. Plates may be A-36 steel and should be thick enough to

resist all driving stresses, plates should not extend more than 1/4 in. outside the pipe for exterior

welding.

Figure 18. Conical Pile

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Monotube and Tapertube Pile

Monotubes are not commonly used, but tapered Monotubes have been used in J.F.K. Airport New York.

Table 6. Monotube pile specifications and details (Hanning, 2013).

Pile Type: Monotube Pile Specifications And Details

Typical Lengths 15 to 80 feet

Material Specifications ASTM A252, Grade 3 (Fy=45.0 KSI) SAE-1010 for steel (Fy=50 ksi) ACI 318-for concrete

Maximum Stresses Typical Design Stress: o.25 Fy to 0.33 Fy (on steel) + 0.40fc (on concrete) Driving Stress: 0.90 Fy 31.5 to 40.5 ksi


Advantages Can be inspected after driving. Tapered pile section provides high resistance in granular soils.

Disadvantages Soil displacement.

Remarks Best for friction pile in granular soils.

Figure 19. Monotube Pile

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Figure 20. Tapered tube

Figure 21. Monotubes are spliced with cutting V notches and grinding the notch, and then fillet weld in order to complete the splicing procedure.

Concrete piles Concrete Piles are typically made with steel reinforcements and pre-stresses tendons to obtain strength

required, to survive handling and driving, and to provide sufficient bending resistance. Long piles can be

difficult to handle and transport. Pile joints can be used to join two or more short piles to form one long

pile. Pile joints can be used with both precast and pre-stressed concrete piles.

Note that in below classification, pre-stressed concrete piles and precast piles may have significant

overlaps in their specifications due to the fact that some piles are precast and reinforced concrete piles.

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Pre-stressed Concrete Piles

Pre-stressed concrete in superstructure design is made of higher strength concrete, requires smaller

cross-sectional area and can be made impact-resistant. The same results apply to pre-stressed piles

relative to comparison with precast reinforced piles. Their advantages compared to precast reinforced

are:

Handling stresses can be resisted by a smaller cross- section which can result in a more

economical pile.

It is easier with the smaller section to achieve longer penetration into load-bearing gravels.

Tensile stresses that are generated up from the toe of the pile after the hammer blow can be

compensated for by pre-stress.

The reduction of tensile cracking of the concrete can lead to greater durability.

The disadvantages of pre-stressed piles are:

The smaller section provides less end bearing and total peripheral skin friction.

Deeper penetration into end-bearing strata (gravel, compact sand, etc.) may be necessary.

It is more difficult to extend the length of a precast driven pile.

As in pre-stressed concrete superstructure elements, stricter quality control in manufacture is

necessary.

Figure 22. Pre-Stressed Concrete shapes.

Typical Sizes:

10 to 20 inches

Typical Sizes:

20 to 36 inches

11 to 18 inches

void

Typical Sizes:

20 to 24 inches

11 to 15 inches

void

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Figure 23. Circular pre-stressed concrete piles.

Figure 24. Square pre-stressed and reinforced concrete piles.

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Table 7. Summary of Pre-Stressed Concrete Pile's Specifications (Hanning, 2013).

Pile Type: Pre-Stressed Concrete Specifications And Details


Material Specifications ACI 318-for concrete ASTM A-416, A-421 and A-882 for pre-stress

Maximum Stresses Typical Design Stress: 0.33 f’c-0.27fpe (on gross concrete area) Driving Stress: 0.85 f’c-fpe (in compression) 3sqf’c+fpe (in tension)


Advantages High load capacity. Corrosion resistance obtainable. Hard driving possible.

Disadvantages Higher breakage rate. Soil displacements. Can be difficult to splice.

Remarks Cylinder piles well suited for bending resistance.

Concrete pile splicing

A pile splice joins two segments of a driven pile, using either a weld (typical for H beams), grout or

mechanical means (typical for precast concrete piles). Pile splices enable the use of shorter segments,

which allows for driving piles in low-headroom situations such as under bridges or inside

buildings. Reducing length of pile segments to under 65 feet long also means the trailers that haul them

to job sites can stay within state length limits. Most of these types are illustrated below. Variations in

construction with actual splices may be encountered.

Figure 25. Mechanical splice

https://en.wikipedia.org/wiki/Deep_foundation#Driven_foundations

https://en.wikipedia.org/wiki/Welding

https://en.wikipedia.org/wiki/I-beam

https://en.wikipedia.org/wiki/Grout

https://en.wikipedia.org/wiki/Deep_foundation#Prestressed_concrete_piles

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Figure 26. Most common types of concrete splices.

Figure 27. An example of Dowel splicing.

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Precast

Precast concrete is a construction product produced by casting concrete in a reusable mold or "form"

which is then cured in a controlled environment, transported to the construction site and lifted into

place.

This type is commonly used where:

The length required can be realistically predicted.

Lateral pressure from a stratum within the soil profile is sufficient to squeeze (neck) a cast-in-

situ pile.

Where there are large voids in sections of the soil which would possibly have to be filled with an

excessive amount of in situ concrete or could cause loss of support for wet concrete prior to

setting.

For structures such as piers and jetties above water level on coastal, estuary and river sites.

Though precast piles can be manufactured on site it is more common to have them designed,

manufactured and installed by specialist subcontractors.

There are disadvantages in the use of precast concrete piles as follows:

It is not easy to extend their length.

They are liable to fracture when driven into such obstacles as large boulders in boulder clay and

the damage can remain out of sight.

Obstructions can cause the pile to deflect from the true vertical line.

There is an economic limit, restricted by buckling, of the unrestrained length of the pile.

Noise and vibration caused by driving can cause nuisance and damage.

There can be large wastage and health and safety risks to the workforce caused by noise and

vibration due to the need to cut off the projecting length after driving.

The accuracy of the estimated length is only proved on site when short piles can be difficult to

extend and long piles can prove to be expensive and wasteful.

The relatively large rig required for driving often needs extensive hard-standings to provide a

suitable surface for pile driving.

The advantages of precast concrete piles are:

It is easier to supervise the initial quality of construction in precast than in situ.

The pile is not driven until the concrete is matured.

Stresses due to driving are usually higher than those due to foundation loading so that

manufacturing faults are more easily discovered and, in effect, the pile is preload tested

(provided the defects can be detected).

The reinforcement, while adding to the load-bearing capacity, is mainly designed to cope with

handling, transporting and driving stresses.

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Figure 28. Spun Cast Cylinder Piles (precast cylinder piles), with no reinforcement.

Table 8. Specification for Cylinder Piles (Hanning, 2013).

Pile Type: Cylinder Piles Specification

Pile Properties High strength concrete, f’c=7 ksi, fpe=1.2 ksi

Typical Sizes 36, 42, 48, 54 and 66 inch for O.D. (see figure ) 5 and 6 inch wall

Typical Design Loads 250 to 800 tons

Figure 29. Cross section of pre-stressed reinforced precast cylinder pile.

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Cast in situ

There is an ever increasing variety of cast in situ piles offered by specialist piling subcontractors. The

piles are usually circular in cross-section and are regarded as small- diameter piles when their diameters

are from 250–600 mm and larger-diameter piles when their diameters exceed 600 mm; large-diameter

piles are now possible with diameters up to 3.0 m. different processes are in the following section, but

the general idea of cast in place concrete piles are depicted in figure 26.

The advantages of cast in situ piles are:

They can be constructed immediately, thus cutting out the time required for casting, maturing

and delivering of precast piles.

There is no need to cut off or extend excessive lengths of the piles as they can be cast in situ to

the required level.

They can be cast to longer lengths than is practical with precast piles.

Most obstructions can be hammered and broken through by the pile-driving techniques.

The placing can cause less noise vibration and other disturbance compared to driving precast

piles.

Soil taken from boring can be inspected and compared with the anticipated conditions.

The disadvantages of cast in situ piles are:

It can be difficult to place and ensure positioning of any necessary reinforcement.

Concrete quality control is more difficult.

There is a danger of necking from lateral earth pressure.

Young concrete is susceptible to attack from some soil chemicals before it has set and hardened.

Figure 30. General concept if cast in place concrete piles.

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Under-Reamed Piles

Under reamed piles have mechanically formed enlarged bases that have been as much as 6 m in diameter.

According to the research carried out at Central Building Research Institute Roorkee (INDIA) and

elsewhere it is found that under reamed piles provide an ideal solution for foundation in black cotton soil.

The form is that of an inverted cone and can only be formed in stable soils. In such conditions they allow

very high load bearing capacities.

The diameter of the pile stem (D) varies from 20 to 50 cm. The diameter of the under-ream bulbs (Du) is

normally 2.5 times the diameter of the pile stem. It may however, vary from 2 to 3 times (D) under special

circumstances. In case of double or multi-under-reamed piles, the center to center vertical spacing

between two bulbs may vary from 1 ¼ to 1 ½ times the under-reamed diameter (Du). The length of under-

reamed piles varies from 3 to 8 meter and their center to center spacing should normally be not less than

2 times the under-reamed diameter, see figure 27.

Figure 31. Under reamed pile with two under reams.

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Under reamed piles are the most safe and economical foundation in Black cotton soil. Under reamed piles

are bored cast in situ concrete piles having bulb shaped enlargement near base. A Pile having one bulb is

called single under reamed pile. In its closed position, the under reamer fits inside the straight section of

a pile shaft, and can be expanded at the base of the pile to produce the enlarged base.

The cost advantages of under-reamed piles are due to the reduced pile shaft diameter, resulting in less

concrete needed to replace the excavated material.

The shape and the dimension of the base widening depend on the type of belling tool used: standard

reamer or bucket reamer ‘bottom hinge’ which has a bell shape (left of Figure 28). Franki uses the 'top

hinge' under-reaming model (belling bucket) or standard reamer (right of Figure 28), usually cut at 45 or

60 degree angle, with the maximum diameter of the under-ream being not more than three times the

diameter of the shaft, see figure below (Figure 28).

Figure 32. Under-Reaming tool is shown in the left, and Franki piling method tools is shown on the right side of the picture.

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Augercast Pile

Augercast piles, also known as continuous flight auger piles (CFA), are deep foundation elements that are

cast-in-place, using a hollow stem auger with continuous flights. The auger is drilled into the soil and/or

rock to design depth. The auger is then slowly extracted, removing the drilled soil/rock as concrete or

grout is pumped through the hollow stem. The grout pressure and volume must be carefully controlled to

construct a continuous pile without defects. Reinforcing steel is then lowered into the wet concrete or

grout. The finished foundation element resists compressive, uplift and lateral loads. The technique has

been used to support buildings, tanks, towers and bridges.

Figure 33. Schematic of an Augering machine.

Figure 34. Auger cast piles for a new Gouverneur Healthcare Services building in downtown Manhattan.

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Franki Piles

Franki Piles, also known as Pressure Injected Footings (PIFS), are high-capacity cast-in-place deep

foundation elements constructed using a drop weight and casing. A 2 to 3 foot diameter steel casing is

vertically positioned at a planned PIF location. The bottom 3 to 5 feet of the casing is filled with a very dry

concrete mix. A steel cylinder with a diameter slightly less than the casing is then repeatedly dropped

inside the casing on the dry mix. The mix locks into the bottom of the casing and the repeated blows of

the drop weight advance the casing to the design depth. The casing is then restrained from further

advancement and additional weight drops expel the dry mix out of the bottom of the casing. Additional

dry mix is added and driven from the casing until a design resistance to further displacement is achieved.

Reinforcing steel and concrete are then placed in the casing and the casing is extracted. The finished

foundation element resists compressive, uplift and lateral loads. The technique has been used to support

buildings, tanks, towers and bridges.

Figure 35. Schematic of a Franki pile procedure.

Figure 36. Franki piles to support the Worcester Trial Court House in Worcester, MA.

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Composite Piles In general, a composite pile is made up of two or more sections of different materials or different pile

types. The upper portion could be eased cast-in-place concrete combined with a lower portion of timber,

steel H or concrete filled steel pipe pile.

Table 9. Composite Pile specifications (Hanning, 2013).

Pile Type: Composite Pile Specifications And Details


Material Specifications ASTM A-572 for H-pile sections ASTM A-252 for pile sections ACI 318 for concrete ASTM D25 for timber sections

Maximum Stresses Typical Design Stress: Depends on pile materials Driving Stress: Depends on pile materials


Advantages May solve unusual design or installation problems. High capacity may be possible depending on pile materials. May reduce foundation costs.

Disadvantages May be difficult to attain good joint between pile materials.

Remarks Weakest pile material controls allowable stresses and capacity.

Figure 37. Concrete and H-Pile composite pile (Hanning, 2013).

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Other Piles

Vibro replacement (Stone Columns)

Vibro replacement is a ground improvement technique that constructs dense aggregate columns (stone

columns) by means of a crane-suspended downhole vibrator, to reinforce all soils and densify granular

soils. Vibro replacement stone columns are constructed with either the wet top feed process, or the dry

bottom feed process.

Figure 38. Stone Column pile procedure.

Micropiles

Micropiles, also known as minipiles, (and less commonly as pin piles, needle piles and root piles) are deep

foundation elements constructed using high-strength, small-diameter steel casing and/or threaded bar.

Capacities vary depending on the micropile size and subsurface profile. Allowable micropile capacities in

excess of 1,000 tons have been achieved (Barry D. Siel).

The micropile casing generally has a diameter in the range of 3 to 10 inches. Typically, the casing is

advanced to the design depth using a drilling technique. Reinforcing steel in the form of an all-thread bar

is typically inserted into the micropile casing. High-strength cement grout is then pumped into the casing.

The casing may extend to the full depth or terminate above the bond zone with the reinforcing bar

extending to the full depth. The finished micropile (minipile) resists compressive, uplift/tension and lateral

loads and is typically load tested in accordance with ASTM D 1143 (compressive), ASTM D 3689

(uplift/tension), and ASTM D 3966 (lateral). The technique has been used to support most types of

structures, see Figure 34.

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Figure 39. Micropiles

Figure 40. Micropiles for seismic retrofit of a parking garage in Spartanburg, SC.

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Summary

Timber Piles Table 10. Timber Pile Specifications (Hanning, 2013).

Pile Type: Timber Specifications And Details

Typical Lengths 15 to 75 ft.-Southern Pile 15 to 120 ft.-Douglas Fir

Material Specifications ASTM D-25

Maximum Stresses Typical Design Stress: 0.81 to 1.2 ksi Driving Stress: 3 Times The Design Stress


Advantages Comparatively low initial cost. Easy to handle. Resistance to decay if permanently submerged.

Disadvantages Vulnerable to decay if untreated and intermittently submerged. Vulnerable to damage at pile head and pile toe in hard driving. Difficult to splice.

Remarks Best suited for friction pile in granular soil

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H-Piles Table 11. Steel H-Pile Specifications (Hanning, 2013).

Pile Type: H-Piles Specifications And Details


Material Specifications ASTM A-572, A-588, A-690

Maximum Stresses Typical Design Stress: 12.5 to 16.5 Driving Stress: 45 ksi

Design Loads Standard H section (8 to 14 inch): 66 to 284 tons Newer H sections (16 to 18 inch): 161 to 495 tons

Advantages Available in various sizes, sections and lengths. Easy to splice. High capacities possible. Low soil displacements. May penetrate larger obstructions with driving shoes.

Disadvantages Vulnerable to corrosion. Not recommended as friction pile in granular soil.

Remarks Best suited for toe bearing on rock.

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Open End Pipe Pile Table 12. Open End Pipe Pile Specifications (Hanning, 2013).

Pile Type: Open End Pipe Pile Specifications And Details





Advantages Available in various lengths, diameters and wall thicknesses. Pile can be cleaned out and driven deeper. Easy to splice. Good resistant's to damage from pile driving operations. Can be installed with conventional equipment. High capacities possible. Low soil displacements.

Disadvantages Vulnerable to corrosion. When driven open ended pile can become plugged with soil requiring pile to drilled or "cleaned" out

Remarks High bending resistance on un supported length.

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Closed End Pipe Pile Table 13. Detailed specifications for Closed End Steel Pipe (Hanning, 2013).

Pile Type: Closed End Pipe Pile Specifications And Details





Advantages Available in various lengths, diameters and wall thicknesses. Easy to splice. Good resistant's to damage from pile driving operations. Can be installed with conventional equipment. High capacities possible.

Disadvantages Vulnerable to corrosion. Soil displacements and can result in soil heave.

Remarks High bending resistance where unsupported length is laterally loaded.

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Monotube Pile Table 14. Monotube pile specifications and details (Hanning, 2013).

Pile Type: Monotube Pile Specifications And Details


Material Specifications ASTM A252, Drage 3 (Fy=45.0 KSI) SAE-1010 for steel (Fy=50 ksi) ACI 318-for concrete

Maximum Stresses Typical Design Stress: o.25 Fy to 0.33 Fy (on steel) + 0.40fc (on concrete) Driving Stress: 0.90 Fy 31.5 to 40.5 ksi


Advantages Can be inspected after driving. Tapered pile section provides high resistance in granular soils.

Disadvantages Soil displacement.

Remarks Best for friction pile in granular soils.

36


Pre-Stressed Concrete Table 15. Summary of Pre-Stressed Concrete Pile's Specifications (Hanning, 2013).

Pile Type: Pre-Stressed Concrete Specifications And Details


Material Specifications ACI 318-for concrete ASTM A-416, A-421 and A-882 for pre-stress

Maximum Stresses Typical Design Stress: 0.33 f’c-0.27fpe (on gross concrete area) Driving Stress: 0.85 f’c-fpe (in compression) 3sqf’c+fpe (in tension)


Advantages High load capacity. Corrosion resistance obtainable. Hard driving possible.

Disadvantages Higher breakage rate. Soil displacements. Can be difficult to splice.

Remarks Cylinder piles well suited for bending resistance.

Cylinder Piles Table 16. Specification for Cylinder Piles (Hanning, 2013).

Pile Type: Cylinder Piles Specification

Pile Properties High strength concrete, f’c=7 ksi, fpe=1.2 ksi

Typical Sizes 36, 42, 48, 54 and 66 inch for O.D. (see figure ) 5 and 6 inch wall

Typical Design Loads 250 to 800 tons

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Composite Pile Table 17. Composite Pile specifications (Hanning, 2013).

Pile Type: Composite Pile Specifications And Details


Material Specifications ASTM A-572 for H-pile sections ASTM A-252 for pile pile sections ACI 318 for concrete ASTM D25 for timber sections

Maximum Stresses Typical Design Stress: Depends on pile materials Driving Stress: Depends on pile materials


Advantages May solve unusual design or installation problems. High capacity may be possible depending on pile materials. May reduce foundation costs.

Disadvantages May be difficult to attain good joint between pile materials.

Remarks Weakest pile material controls allowable stresses and capacity.

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Tables Table 1. Timber Pile Specifications (Hanning, 2013). .................................................................................... 7

Table 2. Steel H-Pile Specifications (Hanning, 2013). ................................................................................... 8

Table 3. This table provides detailed measures for different types of H-Piles ........................................... 10

Table 4. Open End Pipe Pile Specifications (Hanning, 2013). ..................................................................... 11

Table 5. Detailed specifications for Closed End Steel Pipe (Hanning, 2013). ............................................. 13

Table 6. Monotube pile specifications and details (Hanning, 2013)........................................................... 15

Table 7. Summary of Pre-Stressed Concrete Pile's Specifications (Hanning, 2013). .................................. 19

Table 8. Specification for Cylinder Piles (Hanning, 2013). .......................................................................... 22

Table 9. Composite Pile specifications (Hanning, 2013). ............................................................................ 28

Table 10. Timber Pile Specifications (Hanning, 2013). ................................................................................ 31

Table 11. Steel H-Pile Specifications (Hanning, 2013). ............................................................................... 32

Table 12. Open End Pipe Pile Specifications (Hanning, 2013). ................................................................... 33

Table 13. Detailed specifications for Closed End Steel Pipe (Hanning, 2013). ........................................... 34

Table 14. Monotube pile specifications and details (Hanning, 2013). ....................................................... 35

Table 15. Summary of Pre-Stressed Concrete Pile's Specifications (Hanning, 2013). ................................ 36

Table 16. Specification for Cylinder Piles (Hanning, 2013). ........................................................................ 36

Table 17. Composite Pile specifications (Hanning, 2013). .......................................................................... 37

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Figures Figure 1. End Bearing and Friction Force against the Super Structure Load ................................................ 2

Figure 2. Transfer of load to piles are shown in this Figure. ......................................................................... 2

Figure 3. General classification of load bearing piles. .................................................................................. 3

Figure 4. A pile driving rig while driving a pile (HaywardBaker, 2015) ......................................................... 4

Figure 5. A schematic of pile driving procedure (HaywardBaker, 2015). ..................................................... 4

Figure 6. Schematic of an Auger Rig drilling a hole in which it will later be filled with reinforcements and

concrete (HaywardBaker, 2015). .................................................................................................................. 5

Figure 7. Drilled shafts for the Wangum Road Bridge replacement in Moira, NY (HaywardBaker, 2015). .. 5

Figure 8. Classification of piles with respect to their material. .................................................................... 6

Figure 9. Timber Piles driven to the soil, Timber piles are usually suitable for granular soil. ...................... 7

Figure 10. Types of common steel piles. From left to right, H-Piles, Box-Piles, Tube-Piles. ......................... 8

Figure 11. Driven H-Piles surrounded by Sheet Piles .................................................................................... 9

Figure 12. A new type of H-Pile, the section is 18 inches, shown in the picture. ......................................... 9

Figure 13. An H-Pile splicer is shown in this figure. Splicers are used to extend the piles if needed ......... 10

Figure 14. Open End Pipe Piles, ASTM A-252 Steel..................................................................................... 11

Figure 15. Driving procedure of Open End Pipe Piles. ................................................................................ 12

Figure 16. Driving procedure of Open End Pipe Piles. ................................................................................ 12

Figure 17. Closed End Pipe Pile ................................................................................................................... 13

Figure 18. Conical Pile ................................................................................................................................. 14

Figure 19. Monotube Pile............................................................................................................................ 15

Figure 20. Tapered tube .............................................................................................................................. 16

Figure 21. Monotubes are spliced with cutting V notches and grinding the notch, and then fillet weld in

order to complete the splicing procedure. ................................................................................................. 16

Figure 22. Pre-Stressed Concrete shapes. .................................................................................................. 17

Figure 23. Circular pre-stressed concrete piles. ......................................................................................... 18

Figure 24. Square pre-stressed and reinforced concrete piles. .................................................................. 18

Figure 25. Mechanical splice ....................................................................................................................... 19

Figure 26. Most common types of concrete splices. .................................................................................. 20

Figure 27. An example of Dowel splicing. ................................................................................................... 20

Figure 28. Spun Cast Cylinder Piles (precast cylinder piles), with no reinforcement. ................................ 22

Figure 29. Cross section of pre-stressed reinforced precast cylinder pile. ................................................. 22

Figure 30. General concept if cast in place concrete piles. ........................................................................ 23

Figure 31. Under reamed pile with two under reams. ............................................................................... 24

Figure 32. Under-Reaming tool is shown in the left, and Franki piling method tools is shown on the right

side of the picture. ...................................................................................................................................... 25

Figure 33. Schematic of an Augering machine. ........................................................................................... 26

Figure 34. Auger cast piles for a new Gouverneur Healthcare Services building in downtown Manhattan.

.................................................................................................................................................................... 26

Figure 35. Schematic of a Franki pile procedure. ....................................................................................... 27

Figure 36. Franki piles to support the Worcester Trial Court House in Worcester, MA. ............................ 27

Figure 37. Concrete and H-Pile composite pile (Hanning, 2013). ............................................................... 28

Figure 38. Stone Column pile procedure. ................................................................................................... 29

Figure 39. Micropiles................................................................................................................................... 30

https://d.docs.live.net/10241cd8f55b0536/Documents/Foundation/Classification%20of%20piles%20(Recovered).docx#_Toc443743874





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Figure 40. Micropiles for seismic retrofit of a parking garage in Spartanburg, SC. .................................... 30

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References Barry D. Siel, P. IMPLEMENTATION OF MICROPILES.

en.wikipedia.org/wiki/Pile_splice.

engineerengineering.blogspot.com.

Hanning, P. (2013). Pile Types. GRL Engineers, Inc.

HaywardBaker. (2015). Hayward Baker Inc.

Rollins, M. Timber Piling Design. Timber Piling Council.

sdshengya.en.made-in-china.com.

wsuzana.wordpress.com.

www.aboutcivil.org.

www.abuildersengineer.com.

www.ffgb.be.

www.junttan.com.

www.pilebuckinternational.com.

www.pilebuckinternational.com.

www.pilingcontractors.com.au.

www.theconstructor.org.

www.understandconstruction.com/pile.