چكيده به لاتين
In the connected pile-raft system, due to the production of flexural anchors and large axial stresses at the junction of raft and piles and subsequent cracking in the piles, severe structural restrictions are applied. Therefore, the use of Nonconnected pile-raft system as a new approach in civil engineering, especially in tall structures, has been considered by researchers. In this foundation system, the piles do not have a structural connection with the raft and a dense layer of sand pad is used between them, which reduces the stresses and bending moment at the top of the piles. Therefore, the regulatory limitations for a Nonconnected pile-raft system are less than for a connected pile-raft system, and it provides a cost-effective design of the pile-raft foundation system. Nonconnected piles improve the mechanical properties of the substrate by reinforcing the subsoil, which reduces the foundation settlements. In the present study, the response of a Nonconnected pile-raft system with inclined piles under seismic load has been investigated by finite element method and numerical simulation. In the first stage, in order to validate the numerical model, the results of numerical analysis of Nonconnected piles with vertical piles are compared with the results obtained from the seismic test. In the next step, with the help of numerical modeling, parametric studies have been performed to investigate the effect of the angle of inclination of Nonconnected piles on the seismic response of the foundation and considering three types of profiles for sand soil. Based on the results obtained in a specific soil profile, the angle of inclination of the Nonconnected piles does not have a significant effect on the seismic response of the foundation system. Observations also indicate that the type of soil profile strongly affects the response of the Nonconnected pile-raft foundation system.
