槽形梁动力反应分析的能量变分法  

Dynamic response of U-shape beams in consideration of shear lag effect

作　　者：甘亚南[1] 周广春[2] 赫中营[3] 

机构地区：[1]盐城工学院土木工程学院,江苏盐城224051 [2]哈尔滨工业大学土木工程学院,哈尔滨150090 [3]河南理工大学土木工程学院,河南焦作454010

出　　处：《振动与冲击》2010年第11期195-198,共4页Journal of Vibration and Shock

基　　金：国家自然科学基金(50578054)资助项目

摘　　要：以分析箱形梁剪滞效应提出的方法为基础,考虑了剪滞翘曲应力的自平衡条件,为了准确反应槽形梁翼板的动位移变化,三个广义动位移η(x,y,z,t)、w(x,t)和θ(x,t)被引入。利用能量变分原理建立了槽形梁动力反应w(x,t)、u(x,t)和θ(x,t)的控制微分方程和自然边界条件,获得了相应广义位移的闭合解,据此对槽形梁的动力反应特性进行了研究,揭示了槽形梁桥动力反应的规律。算例中,该解析解与有限元数值解进行了比较,证明了该动力分析方法的有效性。Based on the analysis methods of shear lag effect of box girders,a new warping displacement model of an U-shaped beam was chosen to meet the axial self-equilibrium conditions for the corresponding stresses.Three generalized displacement functions η(x,y,z,t),w(x,t),and θ(x,t) were introduced in analyzing dynamic response of the U-shaped beam in consideration of shear lag effect using the energy-variation principle.The differential equations and the corresponding natural boundary conditions of the U-shaped beam were derived based on the minimum potential principle.According to the fundamental differential equations and the corresponding natural boundary conditions,the dynamic characteristics of U-shaped beams were discussed.In calculation examples,the finite element solutions were compared with the analytical solutions,the results verified the validity of the proposed approach.

关 键 词：槽形梁 剪力滞后 动力反应 能量变分原理 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]