基于联动迭代及Heaviside函数的铁路桥墩刚度和位移计算方法  

Method for Calculating Stiffness and Displacement of Railway Bridge Piers Using Linkage Iteration and Heaviside Function

作　　者：王雨权 管仲国[2] 霍学晋[3] 苏伟 廖立坚 WANG Yuquan;GUAN Zhongguo;HUO Xuejin;SU Wei;LIAO Lijian(Civil Engineering Design Research Department,China Railway Design Corporation,Tianjin 300308,China;College of Civil Engineering,Tongji University,Shanghai 200092,China;Scientific Research Institute,China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]中国铁路设计集团有限公司土建工程设计研究院,天津300308 [2]同济大学土木工程学院,上海200092 [3]中铁大桥勘测设计院集团有限公司科研院,湖北武汉430056

出　　处：《铁道学报》2023年第3期88-96,共9页Journal of the China Railway Society

基　　金：中国铁路设计集团有限公司科技开发课题(2021A240602)。

摘　　要：为提高铁路简支梁桥墩刚度及墩顶位移计算的准确度及通用性,克服桥墩及桩基设计中无法实时考虑桩-土耦合作用对刚度的影响,提出一种基于联动迭代及利用Heaviside函数的铁路桥墩刚度及位移计算的广义柔度矩阵法。该算法通过将桩基计算“m”法相关参数代入广义柔度矩阵,实现瞬态反馈桩长及地质变化对桥墩刚度的影响;基于力学等效原则推导集中荷载与分布荷载的等效节点力表达式,并通过将各荷载工况边界条件与Heaviside函数等效置换,得到桥墩单元作用任意形式集中荷载或分布荷载的等效节点力通用完备解;将该算法编入设计程序,实现铁路桥梁桩长、刚度、墩顶位移等参数的精准耦合计算。以变截面圆端形空心桥墩共同作用制动力、纵向风力及土压力为算例,计算结果表明,该算法与3种有限元软件计算的墩顶位移最大误差均在0.600%以内,计算精度高。To improve the accuracy and generality of the calculation of the stiffness and pier top displacement of railway simply-supported beam piers,and to overcome the inability to consider the influence of pile-soil coupling on the stiffness in real time in the design of bridge piers and pile foundations,a generalized flexibility matrix method was developed for calculating the stiffness and displacement of railway simply-supported bridge piers based on linkage iteration and Heaviside function.By substituting the parameters associated with the"m"method of pile foundation computation into the generalized flexibility matrix,the algorithm achieved transient feedback on the effect of pile length and geological changes on pier stiffness.On the basis of the principle of mechanical equivalence,the equivalent nodal force expressions for concentrated and distributed loads were derived.By replacing the boundary conditions of each load condition with the Heaviside function,a generalized and complete solution of the equivalent nodal force was obtained for any form of concentrated or distributed load acting on the bridge pier unit.The algorithm was encoded into the design program for correct coupling computation of rail bridge characteristics including pile length,stiffness,and pier top displacement.The calculation of the joint action of braking force,longitudinal wind force and earth pressure of a hollow bridge pier with trapped round-end shape was conducted.The results show that the maximum error of pier top displacement calculated by the algorithm and the three finite element software programs is within 0.600[WTB4]%,proving high calculation accuracy.

关 键 词：铁路桥 桥墩刚度 广义柔度矩阵 联动迭代 Heaviside函数 通用完备解 

分 类 号：U448.217[建筑科学—桥梁与隧道工程]