陡岩河岸高桩墩式码头群桩基础竖向承载能力

Vertical bearing capacity of group piles foundation of high pile pier type wharf in steep rock bank of river

采用ABAQUS有限元软件模拟斜坡嵌岩群桩(四边形四桩)竖向承载工况、模拟施工过程,考虑材料和桩岩接触非线性影响建立斜坡-嵌岩群桩系统三维模型,通过改变斜坡坡度、桩嵌岩深度等参数分析斜坡嵌岩群桩(四边形四桩)的竖向承载能力。研究表明,不同坡度和嵌岩深度条件下嵌岩群桩(四边形四桩)竖向承载能力,是群桩径向膨胀与桩前岩体缺失效应、桩后岩体增强效应、承台刚度综合作用的体现。群桩效应系数随着坡度的增加(0°≤R≤45°)逐渐增大,坡度较大时(30°≤R≤45°)嵌岩桩群桩(四边形四桩)的承台顶面、各桩桩顶不均匀沉降较明显。

ABAQUS finite element software is used to simulate the vertical bearing condition and construction process of rock-socketed pile(quadrangular pile)on the slope.The nonlinear effects of material and pile-rock contact are taken into account when three-dimensional models of the slope rock-socketed group piles system are established.Based on the change for parameters of slope angle,socketed depth etc.,the vertical bearing capacity of slope rock-socketed group piles is analyzed.Research results show that under different conditions of slope angle and socketed depth,vertical bearing capacity of slope rock-socketed group piles is the comprehensive reflection of radial expansion of group piles,loss effect of rock mass before pile,enhancement effect of rock mass behind pile,and platform stiffness etc.The pile group effect coefficient of group pile increases gradually with the increase of slope angle(0°≤R≤45°).When the slope angle is larger(30°≤R≤45°),the uneven settlement of platform and each pile top of rock-socketed group piles(quadrilateral four piles)is more obvious.