纵向预应力对箱梁剪力滞效应的差分解  

The effects of longitudinal prestressing on the box shear lag by the difference method

作　　者：刘扬[1] 王东东[1] 

机构地区：[1]长沙理工大学土木建筑学院,湖南长沙410004

出　　处：《交通科学与工程》2013年第2期22-27,共6页Journal of Transport Science and Engineering

基　　金：国家自然科学基金项目(50608009;51008036);教育部新世纪优秀人才支持计划(NCET-10-0319);交通部应用基础研究项目(2006319825070;2010318000006)

摘　　要：选取3次抛物线变化的纵向位移,通过能量变分原理得到悬臂箱梁的剪力滞基本微分方程,再利用有限差分法进行求解,将该方法用于分析纵向预应力等效荷载作用下的悬臂箱梁剪力滞效应.运用ANSYS有限元软件建立模型,采用Solid 95单元模拟箱梁,采用Link8单元模拟预应力钢束,分析在纵向预应力作用下箱梁剪滞系数分布规律并与差分法求解的结果进行对比.经过对比,验证了差分法求解纵向预应力等效荷载作用下箱梁剪滞效应的可行性,同时分析了纵向预应力对箱梁剪滞效应的影响.Guided by the energy variational principle and based on the different longitudinal displacements of three parabolas,the basic differential equation of the shear lag of cantilever box girders is obtained,and its feasibility is proved by using the finite difference method.The method is applied to analyze the shear lag effect of cantilever box girder under the longitudinal prestressing of equivalent loaf.Based on the ANSYS,a model which features that the box girder is built and simulated by Solid 95,and the prestressed steel is simulated by Link 10.Later,the model is used to analyze the coefficient distribution rule of the shear lag of the box girder under the longitudinal prestressing,and then this rule is compared with the result from finite difference method.This comparison proves the applicability of the difference method in the study of the shear lag effect of the box girder under longitudinal prestressing of equivalent loaf,and longitudinal prestressing＇s effects on the shear lag effect of beam is also analyzed.

关 键 词：剪力滞 能量变分原理 差分法 纵向预应力等效荷载 

分 类 号：U448.213[建筑科学—桥梁与隧道工程]