倾斜荷载下桩柱式桥墩受力变形分析传递矩阵法  

Transfer Matrix Method for Deformation of Pile Type Bridge Pier Under Axial Transverse Load

作　　者：张玲[1] 赵明华[1] 赵衡[2] 

机构地区：[1]湖南大学岩土工程研究所,湖南长沙410082 [2]中南大学资源与安全工程学院,湖南长沙410083

出　　处：《中国公路学报》2015年第2期69-76,共8页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(50878083)

摘　　要：为了研究倾斜荷载下桩柱式桥墩的受力变形特性,将其视为一工作整体,地面或局部冲刷线以上自由段视为置于虚拟土层中,根据桩(墩)身截面尺寸、混凝土强度等级以及土层情况等将桩柱式结构划分为若干分析单元段,基于Winkler弹性地基梁理论,考虑轴向和横向荷载共同作用,得到任一单元段的位移控制微分方程,并采用幂级数法进行解答。进而根据相邻单元段内力与位移连续条件得到了由柱顶受力与变形条件表示的桩柱式结构任一深度处水平位移、转角、弯矩及剪力的矩阵表达式。通过具体算例将提出的传递矩阵法所得结果与有限元等方法所得结果进行了比较。在此基础上,探讨分析了地基成层性对倾斜荷载作用下桩柱式结构体系内力与位移的影响。研究结果表明:表层土的物理力学性质及埋深对柱顶水平位移、地面处桩身水平位移及桩身最大弯矩值均有不同程度的影响。To study the deformation of pile type bridge pier under axial transverse load,the pile type bridge pier was regarded as an integrated working system,with the free segment above ground or scour line embedded in a virtual layered soil.To simplify the analysis,the pier was divided into several segments according to the cross-section condition,concrete strength condition and soil layer condition.The governing differential equation in term of lateral deflection for each pier segment was obtained on the base of the basic concept of the Winkler elastic beam theory with consideration of axial transverse load.Its relative solution by using the power series method was proposed as well.By considering the deflection and force continuum conditions between two adjacent segments,a matrix form of pile pier response at any depth was expressed through the deflection and lateral force at the pier head.The results obtained from the proposed solution were compared with the results obtained from other existing methods including finite element method.On the base of that,the soil layering effect on the response of the pile pier system was alsodiscussed.The results indicate that the physical-mechanical properties and the depth of the soil in the surface layer have effects on the behavior of pile type bridge pier,reflected in the lateral deflection at the pier top,the lateral deflection of pile body at the ground,and the maximum bending moment within the pile.

关 键 词：桥梁工程 桩柱式桥墩 传递矩阵法 倾斜荷载 成层地基 WINKLER地基模型 

分 类 号：U443.15[建筑科学—桥梁与隧道工程]