桩(墙)单位侧摩阻力与轴向应变关系的解析解及其应用  

Analytical solution for relationship between unit shaft resistance and axial strain of piles or closed diaphragm wall and its application

作　　者：文华[1,2] 程谦恭[1] 宋章[1] 

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]西南科技大学土木工程与建筑学院,四川绵阳621010

出　　处：《岩土力学》2008年第12期3342-3348,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.40172093);国家杰出青年基金(No.40025103);交通部西部交通建设科技项目基金(No.200331849457);西南交通大学2008年博士研究生创新基金资助项目

摘　　要：根据弹性力学原理,提出了模型筒桩(闭合墙)的简化力学模型。采用半逆解法先求出桩左右侧受均布摩阻力、桩顶受均布荷载两种情况下的应力分量,根据叠加原理得出桩两侧均受相同摩阻力、桩顶受均布荷载情况下的应力分量。据此推导了普通桩基的轴力和侧摩阻力计算式,分析结果表明,该计算式与传统计算方法是一致的。当桩壁两侧受不同大小的侧摩阻力、桩顶受均布荷载时,仍采用叠加原理求得各应力分量,进而求得桩表面处的轴向应变与单位侧摩阻力关系的解析解。通过矩形闭合墙基础模型试验实例,对该解析解的应用方法加以说明。该解析解的求出,为竖向载荷试验中模型筒桩(闭合墙)所量测的内外侧应变进行数据处理提供了理论依据,进而为基础-土相互作用研究提供了真实、准确的试验结果。Simplified mechanical model of tubular pile or closed diaphragm wall is proposed base on elasticity mechanics. The stress components of piles in two load conditions are solved by semi-inverse method at ftrst. One load condition is that uniform vertical shear stress acted on the left and right sides of pile shaft, another is uniform vertical shear stress acted on the pile top. According to superposition principle, the stress components of the pile with unit shaft resistance on both side and vertical load on the head are solved. The calculating formulation of axial force and unit shaft resistance are deduced; and good identity has been achieved between the formulation and traditional method. When uniform vertical shear stress is not equal on both sides, the stress components of the vertical loaded pile are also solved according to superposition principle. Then an analytical solution of unit shaft resistance-axial strain relationship by using semi-inverse method is obtained. Application of the analytical solution is illustrated with a model test of closed diaphragm wall. This solution will provide theoretical basis for data processing of outer and inner axial strains which are measured in the model test of axial loaded cast-in-situ tubular piles or closed diaphragm wall. Thus true and accurate test result can be provided for the research on foundation-soil interaction.

关 键 词：单位侧摩阻力 轴向应变 半逆解法 筒桩 矩形闭合地下连续墙 模型试验 数据处理 

分 类 号：TU473[建筑科学—结构工程]