基于综合刚度原理的陡坡基桩有限杆单元分析

Finite Bar Element Analysis of Bridge Pile Foundation in Steep Slopes Based on Composite Stiffness Principle

摘要:

为分析陡坡段桥梁基桩内力及变形特性,提出一种有限杆单元计算方法。首先,基于综合刚度原理并引入双参数地基模型,建立适用于陡坡基桩内力计算分析的修正有限杆单元刚度方程;在此基础上结合杆系结构受力特征,提出考虑P-Δ效应的杆单元修正矩阵;最后,根据有限杆单元计算原理,基于MATLAB平台编制计算程序,并对某工程实例进行分析。计算结果显示:改进有限杆单元方法可行且具有较高的精度;陡坡段桥梁基桩P-Δ效应显著,应在设计计算中予以考虑;在浅层地基土抗力计算中双参数地基模型较m法精度更高。

Abstract:

A finite member element method is proposed for the analysis of the deformation of a bridge slope pile located on a steep slope.A modified finite member element method based on the composite stiffness principle and double-parameter ground model was established that was suitable for the calculation,and analysis of the stresses on the slope pile.Next,taking into account the load response of the bar system,a modified matrix of the bar element incorporating the P-Δ effect was developed.The next step involved writing a MATLAB program which was used to analyze a real example.The results showed that the precise,proposed method was valid.Also,the P-Δ effect was too considerable to be ignored in the design and calculation and double-parameter model works better than m-model on shallow ground.