斜坡段桥梁基桩受力与变形分析的传递矩阵法  

Transfer Matrix Method for Analysis of Stress and Deformation of Bridge Piles in Sloping Ground

作　　者：尹平保 王翱 赵衡[2] 杨铠波 赵明华[2] YIN Pingbao;WANG Ao;ZHAO Heng;YANG Kaibo;ZHAO Minghua(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China;Institute of Geotechnical Engineering,Hunan University,Changsha 410082,China;Key Laboratory of Bridge Engineering Safety Control by Department of Education(Changsha University of Science&Technology),Changsha 410114,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]湖南大学岩土工程研究所,湖南长沙410082 [3]桥梁工程安全控制教育部重点实验室(长沙理工大学),湖南长沙410114

出　　处：《湖南大学学报（自然科学版）》2022年第11期216-224,共9页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(52078055,52178311);长沙理工大学土木工程优势特色重点学科创新性项目(18ZDXK12);长沙理工大学桥梁工程安全控制教育部重点实验室开放基金资助项目(18KB01);湖南省教育厅科学研究项目(20A001,20B040)。

摘　　要：根据斜坡段桥梁基桩的水平承载特性,建立了考虑斜坡效应的桩-土相互作用模型及挠曲微分方程;基于m法和传递矩阵法,推导了桩身内力与位移分析的传递矩阵解答;通过模型试验,测得了黏土和砂土斜坡地基比例系数,拟合得到了斜坡地基比例系数与坡度间的关系式,验证了理论解答的合理性;以某工程实例为基础,分析了斜坡坡度和桩顶水平荷载对斜坡基桩受力与变形的影响.研究表明:斜坡地基比例系数随桩土交界面处桩身水平位移增大而呈非线性关系减小;黏土和砂土斜坡地基比例系数均随斜坡坡度增加而减小;基桩桩顶水平位移和桩身最大弯矩均随斜坡坡度和桩顶水平荷载增加而增大;当斜坡坡度由0°增加至60°时,桩顶水平位移约增大86.4%,桩身最大弯矩约增大4.6%,桩身最大弯矩位置约下移2.0 m;桩顶水平荷载每增加50 kN,桩顶水平位移平均增大48.5%,桩身最大弯矩平均增大41.6%.According to the lateral bearing characteristics of bridge piles in sloping ground,the pile-soil interaction model considering the slope effect and the differential equation of flexural deformation was established.Based on the m method and transfer matrix method,the transfer matrix solution of pile internal force and displacement analysis was derived.The proportional coefficient of clay and sand slope foundation were measured by model tests.The relationship between the proportional coefficient of slope foundation and slope angles was obtained by nonlinear fitting,and then the rationality of theoretical solutions was verified by the model test.Based on an engineering example,the influence of slopes and horizontal loads on the internal force and deformation of piles in the sloping ground were analyzed.The results show that:the proportional coefficient of sloping ground decreases nonlinearly with the increase of horizontal displacement of the pile at the pile-soil interface.The proportion coefficients of clay and sand sloping grounds decrease with the increase of slope angles.The horizontal displacement of the pile top and the maximum bending moment of the pile body increase with the increase of slope angles and horizontal loads.When the slope angle increases from 0°to 60°,the horizontal displacement of the pile top increases by about 86.4%,the maximum bending moment of the pile body increases by about 4.6%,and the position of the maximum bending moment move down by about 2.0 m.When the horizontal load is increased by 50 kN,the horizontal displacement is increased by 48.5%and the maximum bending moment is increased by 41.6%on average.

关 键 词：桩基础 斜坡 传递矩阵法 地基比例系数 模型试验 

分 类 号：TU473[建筑科学—结构工程]