筏－桩－土共同作用分析方法

Analyzing Method for Raft-piles-soil Interaction

提出了一种分析筏－桩－土共同作用工作性状的实用计算方法—位移协调法［１］．该方法假定筏极与桩土地基位移协调，对矩形筏板根据其边界条件和变形性状采用一种双重三角级数位移模式．对拉土地基采用单桩计算方法—考虑桩压缩性的位移协调法［１，２］，分析桩土之间的相互影响。根据位移协调条件和力平衡条件建立筏－桩－土共同作用的分析方程．可求解筏板与桩土地基之间的接触应力、桩土地基的应力及沉降、筏板的沉降、弯矩、扭矩及应力和桩筏基础对周围环境的影响等．文中对桩筏基础、片筏基础及性承台的分析与设计具有理论与实用价值．

In this paper, a practical method, displacement compatibility method for analyzing working characteristics for raft- piles - soil interaction is proposed.It's assumed that the settlement of raft be compatible with that of piles and soil.A bi- triangular seriesed displacement model is adopted according to the boundary condition and deformation characteristics of rectangular raft. Displacement compatibility method in consideration of pile compressibility is used to analyze the mutual influence between piles and soil. Calculation equations for raft-piles-soil interaction are established according to the condition of displacement compatibility and force equlibrium. Contact pressure between raft and piled foundation, stress and settlement of piled foundation, settlement and internal forces of raft, influence on surrounding circumsference of piled raft foundation can be calculated. The method pocesses practical value for piled raft foundation, raft foundation and piled cap analysis and design.