基于Vesic圆孔扩张理论的桩周土抗力计算方法研究

随着目前城市建筑物容量的增大,对作为其主要承载构件的桩基础的承载性能提出了更高的要求.桩-土相互作用问题是桩基水平承载性能研究中必须考虑的重要内容,该问题的研究对于完善桩基础设计理论和指导工程实践具有重要意义.基于Vesic圆孔扩张理论,分析水平荷载作用下桩侧土体的实际受力状态,根据桩身产生水平位移后桩周土应力为近似椭...

Computation Method for Soil Resistance Around Pile Based on Cavity Expansion Theory

The increase in the capacity of urban buildings has led to higher requirements for the bearing capacity of pile foundations. The pile-soil interaction is an important subject in studies on the horizontal bearing capacities of pile foundations, which are of significance to improve the design theory of pile foundations and guide engineering practices. Based on the Vesic expansion theory, according to the characteristics of the soil stress after the horizontal displacement of the pile body, assumed to have an elliptical nonuniform distribution, the effects of the vertical stress changes, rotation and deflection of the pile foundation, and pile-soil friction on the lateral soil resistance were comprehensively considered. A calculation formula for the soil resistance on the pile side under horizontal loads is derived. A method of p-y curve based on the stress increment is obtained. A mechanical model of the pile-soil interaction in a two-dimensional plane state is established. The applicability of the method is verified by examples. The influences of pile and soil parameters are analyzed in detail. According to the comparison of the results calculated using this method to those obtained by the model test, the theoretical method proposed in this study is used for the calculation of the mechanical response of the soil on the pile side under horizontal loads. The results obtained by this method are in good agreement with the measured data in the model test, particularly when a larger horizontal displacement of the pile foundation is produced. Through the computation and analysis of the pile and soil parameters, the influences of the pile diameter, internal friction angle, and deformation modulus of the soil on the soil stress around the pile are analyzed. In addition, the change rules of the radial and tangential stresses of the soil at different locations around the pile are obtained.