将杆系结构有限单元法与荷载传递迭代法相耦合,形成一桩基沉降分析计算的混合法。采用近似解析解中Randolph and Wroth’Model与双曲线模型相结合,模拟桩身与桩周介质边界上剪切滑移的非线性。桩间相互作用在采用弹性理论Mindlin方程解答计算,并考虑了桩间“加筋与遮帘”作用。桩周土介质非均质性特征,采用指数函数模拟。分析了刚性承台下群桩桩数、桩长、桩间距和桩土模量比等群桩工作特性的影响。尤其是桩台基础沉降对群桩相互作用影响机制的研究,对桥梁拼接等对桩基础沉降要求严格的工程有重要的借鉴意义。
Abstract
One hybrid method of finite element analysis of rod structure coupling with load transfer approach for pile group settlement was established. The nonlinear behavior of shear-displacement on the boundary between pile and ground was determined by the Randolph and Wroth’ Model in the approached closed form solution
coupling with the hyperbolic model. The action of pile groups was evaluated from the Mindlin equation solution
and adjusted by the “reinforcement and curtain” action approximately. The nonhomogeneous behaviours of ground between piles is characterized with an exponential function. The influences of number of piles
the pile length
the space between piles
and the pile-soil relative stiffness factor on the characteristic of pile groups were analyzed in a systematic way. The interaction of pile group affected by the settlement of piles with rigid cap was discussed emphatically; and the results may be used for reference in the construction in which the settlement of pile group foundation is limited strictly