梯形箱梁剪力滞后效应的精细化分析  

The delicate analysis of shear lag effect on trapezoidal box girders

作　　者：甘亚南[1] 石飞停[1] 

机构地区：[1]盐城工学院土木工程学院,盐城224051

出　　处：《计算力学学报》2014年第3期351-356,共6页Chinese Journal of Computational Mechanics

基　　金：江苏省高校自然科学研究面上项目(13KJB560014);国家自然科学基金(50678076)资助项目

摘　　要：引入剪滞翘曲应力自平衡条件的影响,考虑了剪切变形和剪滞效应等因素,设置了三个不同的剪滞纵向位移差函数以准确反映梯形箱梁不同宽度翼板的剪滞变化幅度,提出了一种能对工程中常用箱梁静力学特性分析的精确解法。本文以能量变分原理为基础建立了薄壁箱梁的弹性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。算例中,分析了不同荷载形式、跨宽比和悬臂板长度等因素对箱梁静力学特性的影响,结果显示出引入剪滞翘曲应力自平衡条件的必要性。In consideration of self-equilibrium condition for shear lag warping stress,shear deformation and shear lag effect,three different longitudinal displacement difference functions are employed to accurately reflect the amplitude of change of shear lag in the trapezoidal box girders with various widths of wing slabs,and a new warping displacement mode of trapezoidal thin-walled box girders is chosen to meet the axial self-equilibrium condition for corresponding stress,a more accurate approach is proposed to analyze the mechanical characteristics of trapezoidal box girders generally used in engineering.Based on the minimum potential principle,the governing differential equations and related natural boundary conditions are induced,the closed-form solutions of generalized displacements are obtained.The variations of stress of trapezoidal box girders,caused by the change of factors such as self-equilibrium condition,type of loading and ratio of span and width are discussed,the importance about the introduction of self-equilibrium condition is proved.

关 键 词：桥梁工程 自力平衡条件 剪力滞后 能量变分原理 梯形箱梁 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] O312.2[交通运输工程—道路与铁道工程]