宽翼缘薄壁梁剪滞效应分析的变分解法  

A VARIATIONAL APPROACH TO THE ANALYSIS OF SHEAR LAG EFFECT OF THIN-WALLED BEAMS WITH WIDE FLANGE

作　　者：张元海[1] 张清华[2] 李乔[2] 

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]西南交通大学土木工程学院,四川成都610031

出　　处：《工程力学》2006年第1期52-56,共5页Engineering Mechanics

基　　金：甘肃省自然科学基金资助项目(3ZS042-B25-032);兰州交通大学"青蓝"人才工程基金资助项目(QL2004-2-16)

摘　　要：采用三个独立的广义位移w(x)、U(x)、θ(x)对宽翼缘薄壁梁的剪滞效应进行变分法分析,根据最小势能原理,建立了关于w(x)、U(x)、θ(x)的基本微分方程及相应的边界条件。计算体系总势能时考虑了剪力在剪切变形上作功。所推导的基本方程及边界条件表明,剪力滞后效应与剪切效应彼此独立。引用的算例计算结果表明,按该方法计算宽翼缘薄壁梁的挠度,能大幅度提高计算精度。Three independent generalized displacement functions w（x）, U（x）, θ（x） are employed in analyzing shear lag effect of thin-walled beams with wide flange by calculus of variations. The fundamental differential equations in terms of w（x）, U（x）, θ（x） and corresponding boundary conditions are established by means of the principle of minimum potential energy. The work done by shear force on sheafing deformation is taken into consideration when calculating general potential energy of the system. The fundamental equations and boundary conditions indicate that shear lag effect and shear deformation effect are independent. Numerical results of thin-walled beams with wide flange show that the accuracy of deflection is improved significantly.

关 键 词：桥梁工程 剪滞效应 变分法 薄壁粱 剪切效应 

分 类 号：TU338[建筑科学—结构工程]