For civil engineers, end bearing piles are a popular choice for providing foundation support. End bearing piles are capable of transferring a structure’s vertical and lateral loads to more competent bearing strata below a weak superficial layer. Besides efficient load transfer, end bearing piles are also known for their cost-effectiveness and rapid installation time. In this article, we will be describing in detail the characteristics, design considerations, and installation methods of end bearing piles.
End bearing piles are commonly used in both new construction and repair/rehabilitation projects. In fact, they are often used in conjunction with other foundation types, such as friction piles, to create a more comprehensive foundation system. Depending on the soil conditions and the loads that need to be supported, end bearing piles can be designed to be either jacketed or unjacketed.
Jacketed Eng Bearing Piles
Jacketed end bearing piles are typically used in cohesive soils, while unjacketed end bearing piles are used in cohesionless soils. Cohesive soils are made up of particles that are held together by water molecules, while cohesionless soils are made up of particles that are not held together by water molecules. The type of soil you are dealing with will have a major impact on the design of your pile foundation.
If you are working with cohesive soils, the design of your pile will need to account for the fact that cohesive soils can expand and contract when they are wet or dry. This means that the pile needs to be able to accommodate for this movement without affecting the integrity of the foundation. One way to do this is to use a jacketed end bearing pile.
A jacketed end bearing pile is a pile that is surrounded by a casing or sleeve. The sleeve helps to support the pile and prevents it from moving laterally. This type of pile is often used in scenarios where the soil is known to expand and contract.
If you are working with cohesionless soils, the design of your end bearing pile foundation will need to account for the fact that cohesionless soils can be very dense and hard to work with. In general, cohesionless soils have a lower bearing capacity than cohesive soils. This means that the end bearing piles need to be designed to accommodate for the lower bearing capacity. One way to do this is to use an unjacketed end bearing pile.
Unjacketed Eng Bearing Pile
An unjacketed end bearing pile is a pile that is not surrounded by a casing or sleeve. The unjacketed end bearing pile is often used in scenarios where the soil is known to be very dense. Due to the lack of a casing, this type of pile is not as stable as a jacketed end bearing pile. However, it is often more cost-effective.
Once you have decided on the type of end bearing pile you need, the next step is to determine the size and length of the piles. The size of the piles will be dictated by the loads that need to be supported. The length of the end bearing piles will be dictated by the depth of the bearing strata. In general, end bearing piles should be designed to extend at least 600mm into the bearing strata. This value shall be considered as only indication and the designer should determine the depth required based on the condition of the soil.
Once the size and length of the end bearing piles have been determined, the next step is to select an installation method. The most common installation methods are auger cast, driven, and jetted.
Auger cast end bearing piles are installed by drilling a hole into the ground and then filling the hole with concrete. This type of installation is typically used in cohesive soils.
Driven end bearing piles are installed by driving the pile into the ground using a pile driver. This type of installation is typically used in cohesionless soils.
Jetting end bearing piles are installed by using high-pressure water to jet the pile into the ground. This type of installation is typically used in scenarios where the soil is very dense.
Once the end bearing piles have been installed, the next step is to connect the piles to the structure. This is typically done by using steel rods or cables. The connection between the piles and the structure needs to be designed to accommodate for the loads that will be applied to the foundation.
The final step in the design of an end bearing pile foundation is to backfill the area around the piles. The backfill material needs to be chosen carefully to ensure that it does not adversely affect the piles or the structure.
End bearing pile foundations are a great way to support structures in areas where the soil is known to expand and contract. These foundations are also well suited for cohesive and dense soils. When designed properly, end bearing pile foundations can provide years of support for your structure.
