求解倾斜荷载下单桩内力变形的状态空间法  

State Space Approach of Solving Internal Forces and Deformations for a Single Pile under Oblique Loads

作　　者：梅甫良[1] 李桂苓[1] 

机构地区：[1]嘉兴学院建筑工程学院,浙江嘉兴314001

出　　处：《嘉兴学院学报》2015年第6期56-61,共6页Journal of Jiaxing University

基　　金：嘉兴市科技计划项目(2013AY11018)

摘　　要：对倾斜荷载下单桩内力变形的求解提出了一种状态空间法.首先,分别根据Euler-Bernoulli梁理论和Winkler线弹性地基梁理论,建立了地面以上及以下桩身响应的状态方程,其中桩周土对桩身的反力用三参数模型来模拟;其次,为了使上述状态方程线性化,将地面以上和以下桩身等分为若干子段,并设各子段上的地基反力系数、轴力与自由段上水平分布荷载都为常数,建立了地面以上及以下各子段响应的线性化状态方程;再次,利用矩阵理论和边界条件及子段间连续光滑条件,推导出倾斜荷载下桩变形内力的状态空间解,编制了计算程序;最后,研究了轴向荷载对桩顶水平位移和桩身最大弯矩的影响.计算结果表明:本方法和程序是易于使用且可靠的;当轴向荷载或者水平位移较大时,轴向荷载对桩身弯曲变形和内力的影响很大.In the paper,a state space method of solving deformations and internal forces for a single pile subjected to oblique loads is put forward.First of all,state space equations of pile responses above and below ground are set up based on Euler Bernoulli＆#39;s and Winkler＆#39;s linear elastic foundation beam theory in which the reaction of soil surrounding the pile is simulated with a three parameter model.Secondly,to make the above state space equations become linear,the linear state space equations for a pile subsection above and below ground are built up after the pile shafts above and below ground are divided into lots of uniform pile subsections while foundation reaction coefficient ,axial force and lateral load for a pile subsection are supposed to be constant. Thirdly,a state space solution of deformations and internal forces for the single pile under oblique loads is obtained by means of matrix theory,boundary conditions,continuity smooth deformations and internal forces between two adjacent pile subsections.Corresponding calculating program is developed.At last,the effect of axial load on horizontal displacement at the pile head and maximum bending moment are studied.The results reveal that both the present solution and its program are reliable and practicable;the effect of axial load on bending deformations and internal forces is considerately obvious when the axial load or lateral displacement value is much bigger.

关 键 词：土-结构相互作用 倾斜荷载 状态空间法 地基反力法 三参数模型 

分 类 号：TU472[建筑科学—结构工程]