A pile is a slender, structural member installed in the ground to transfer structural loads to the soil at some significant depth below the base of the structure. Structural loads include axial loads, lateral loads and moments. Another term commonly used for pile foundation is deep foundation. Structures that cannot be supported economically on shallow foundations are usually supported by pile foundations.

Based on the material used for the construction of pile foundation, it can be classified into the following 5 types.

  1. concrete piles
  2. steel piles
  3. Timber Stacks
  4. piles of plastic
  5. mixed hemorrhoids

1. concrete piles

There are several types of concrete piles that are commonly used. These include cast-in-place concrete piles, precast concrete piles, drilled shafts and barrett piles. Cast-in-place concrete piles are constructed by driving a cylindrical steel shell into the ground to the desired depth and then filling the cavity of the shell with liquid concrete. They are called displacement piles. The steel shell construction is for convenience and does not contribute to the load transfer capacity of the pile. Its purpose is to open a hole in the ground and keep it open to facilitate the construction of a concrete pile. Plain concrete is used when the structural load is only compacted. If moment and lateral loads are to be transferred, a steel reinforcement cage is used in the upper part of the pile.

Precast concrete piles usually have square or circular or octagonal cross sections and are made in a construction yard or a factory from reinforced or precast concrete. They are preferred when the heap length is known in advance. Disadvantages of precast piles are problems with carrying, cutting and lengthening long piles. A very popular type of precast concrete pile is the Raymond cylindrical precast pile. This pile comes in sections, and by stacking the sections a length of up to 70 meters can be achieved.

Typical design loads are more than 2 MN.

Micropiles (also called minipiles, pin piles, needle piles or root piles) are small-diameter (50 mm to 340 mm) pipe piles (pushed or driven) or grouted (jet or post or pressure) piles.

they are especially useful for

  • sites with low headroom,
  • congested areas,
  • sites with restricted access, and
  • Repair or strengthening of foundations.

2. steel piles

Steel piles come in various shapes and sizes and include cylindrical, tapered and H-piles. Steel H-piles are rolled steel sections. They are non-displacement heaps. Steel pipe stacks are seamless pipes that can be welded to lengths of up to 70 metres. They are generally driven into the soil with open ends. A conical tip is used where the piles have to penetrate stones and rocks. To increase the load capacity of steel pipe piles, earthen plugs are excavated and replaced with concrete. These piles are called steel piles filled with concrete. The mud plug may adhere to the surface of the pile and move down with it during driving. This is called plugging.

3. Timber Piles

Wood piles have been used since ancient times. The length of the wood pile depends on the type of trees used to cut the pile, but the typical length is about 12 metres. Longer lengths can be obtained by joining several piles. Wood piles are susceptible to termites, marine organisms, and rot within areas exposed to seasonal changes. Timber piles are displacement piles.

4. plastic piles

Plastic stacks consist of a variety of composite materials including polymer composites, PVC and recycled materials. These piles are used for specialized applications such as in marine environments and in soil areas exposed to seasonal changes.

5. composite

A composite pile can be made by mixing concrete, steel and wood. For example, that part of a pile of wood above groundwater level that is likely to rot due to termites or rot can be replaced with concrete. Similarly, portions of steel piles within a corrosive environment may be covered with concrete or other protective material.

Also read: How To Calculate Pile Load Capacity? (static analysis)

Also read: How To Calculate Pile Load Capacity In Weathered Rock Or Soft Rock?

Also Read: How To Calculate Pile Load Capacity Using Static Cone Penetration Test?

Also read: How To Calculate Pile Load Capacity Using SPT(N) Values?

Er. Mukesh Kumar

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Er. Mukesh Kumar is Editor in Chief and Co-Funder at Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.