壁板桩承载特性的近似三维分析

Approximate three-dimensional analysis of load-carrying behaviour of barrettes

为考虑壁板桩矩形横截面的非轴对称性,将桩体沿深度和横截面方向进行三维离散,利用Mindlin方程和静力平衡条件分别建立桩周土体和桩体的位移方程,并由此推导了联立求解壁板桩荷载位移关系的支配方程,分析了壁板桩的承载特性。结果表明,在桩土接触面滑移破坏之前,壁板桩的侧壁摩阻力在横截面上的分布并不是均匀的。壁板桩的长宽比对壁板桩的承载特性也有明显的影响。

In order to consider the cross-sectional non-axisymmetrical characteristic, a barrette is discretised three-dimensionally along its depth and across the barrette. The static equilibrium equation and the Mindlin equation are used to establish the displacement equations for the barrette and its surrounding soils respectively. The governing equation of the load-settlement relationship of the barrette is then derived by solving simultaneously the displacement equations. By using this method, the load-carrying behaviour of barrettes is analysed. It is found that a uniformly distributed shaft resistance is not mobilised across the barrette until the slippage failure of the soil nearest the barrette has been reached. The ratio of length to width has distinct influence on the load-carrying behaviour of a barrette.