考虑剪力滞效应的先简支后连续箱梁徐变效应分析  

Creep Analysis of Simply Supported-to-Continuous Box Girders Under Shear Lag Effect

作　　者：孙永新[1] 蔺鹏臻[1] 

机构地区：[1]甘肃省道路桥梁与地下工程重点实验室(兰州交通大学),兰州730070

出　　处：《应用数学和力学》2015年第8期855-864,共10页Applied Mathematics and Mechanics

基　　金：国家自然科学基金(51208242;51368031);甘肃省杰出青年基金(1210RJDA009);中国博士后科学基金(2012M521815);教育部"长江学者和创新团队发展计划"(IRT1139)~~

摘　　要：为了分析混凝土箱梁的徐变效应与剪力滞效应的相互影响,基于箱梁剪力滞效应计算的能量变分方法,推导了混凝土箱梁徐变受剪力滞效应影响的次内力和应力计算公式.结合先简支后连续箱梁算例,计算了受剪力滞效应影响后的徐变弯矩和应力,分析了考虑徐变效应影响的剪力滞系数.结果表明,与不考虑剪力滞效应的结果相比,剪力滞效应增大了箱梁徐变效应.对算例箱梁,考虑剪力滞效应后,对中支点截面处徐变的影响最大,次内力增大42.56%,腹板处应力减小8.5%.To analyze how creep interacts with shear lag effect in concrete box girders, the cal- culation formulae for the creep secondary internal force and stress were derived with the energy variation method. With a simply supported-to-continuous box girder for example, the creep bending moment and stress were calculated under the shear lag effect, and the shear lag coeffi- cients were obtained under the influence of creep. The results show that the shear lag effect in- creases the creep stress significantly. Under the shear lag effect, the creep variation at the inter- mediate bearing section is the maximum, where the secondary bending moment increases by 42.56% and the flange normal stress above the web plate decreases by 8.5%.

关 键 词：混凝土箱梁 剪力滞效应 徐变 先简支后连续 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]