Numerical study of the effect of the type of connection between the pile and the foundation on the bearing capacity and the settlement created in the pile raft foundations

Document Type : Original Article

Authors

Mahdi Yazdi Nasab Karani

Mahmoud Yazdani

Department of Civil Engineering, Tarbiat Modares University, Tehran, Iran

10.22067/jfcei.2025.90657.1328

Abstract

Many studies have been done on the pile raft foundations. However, the effect factor of the type of connection between the piles and the raft foundation has been less studied. The type of rigid connection is a state in there is a bending moment between the pile and the foundation. But in the case of a hinged connection, unlike a rigid connection, the bending moment at the connection between the pile and the foundation is zero. In the non-connected state, the raft foundation is not directly connected to the pile, and a layer of soil is placed between the pile and the foundation. In this research, the effect of the type of connection between the pile and the raft foundation on the performance of the entire system, especially the settlement of the raft foundation, as well as the distribution of the bending moment in the foundation and pile under vertical and lateral static loading was studied. The amount of bending moment created in the pile and foundation under vertical and lateral static loading is the lowest in the detached state and the highest in the rigid connection state. The two states of rigid and hinged connection before the piles reach their maximum bearing capacity (yield point) have a similar behavior. After the yield point of the piles, a lower bending moment is created in the hinged connection state than in the rigid connection state. But the settlement created in the hinged connection mode will be more than the rigid connection.

Keywords

Keywords: Piled raft foundation

Bearing capacity

Non-connected between pile and foundation

Rigid and hinged connected between pile and foundation

Settlement of raft foundation

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