箱梁剪力滞翘曲位移函数理论分析  

Theoretical analysis of shear lag warping displacement function of box girder

作　　者：安平和 邬晓光[2] 时元绪 殷悦 AN Pinghe;WU Xiaoguang;SHI Yuanxu;YIN Yue(Xi'an Highway Research Institute,Xi'an 710000,China;School of Highway,Chang'an University,Xi'an 710064,China)

机构地区：[1]西安公路研究院,陕西西安710000 [2]长安大学公路学院,陕西西安710064

出　　处：《武汉大学学报（工学版）》2020年第8期692-697,共6页Engineering Journal of Wuhan University

基　　金：贵州省交通运输厅科技项目(编号:2015121024);中央高校基本科研业务费专项资金项目(编号:201493212002)。

摘　　要：为了确定合理剪力滞翘曲位移函数,弥补不能从理论分析角度确定翘曲函数的不足,从箱梁翼缘板纵向受力和变形的角度出发将翼缘板合理简化成用弹簧连接的横向相互平行的截面,受到剪力滞影响时翼缘板截面发生纵向弯曲。根据最小势能原理,采用能量变分法推导出纵向位移函数为余弦函数。将此纵向位移函数代入剪力滞变分方程中,得到简支箱梁在均布荷载下的弯曲正应力方程。为验证该方法的正确性,将计算得到的翼缘板纵向正应力,与实测值、代入3次抛物线位移函数的计算值、实体有限元计算值进行比较,结果表明:该方法的计算结果与实测值吻合度较高,与代入3次抛物线位移函数的计算值在翼缘板处也基本吻合,在缺乏实测值的翼板与腹板结合处,计算结果与实体有限元计算结果吻合度较高。In order to determine the reasonable shear lag warping displacement function,and to make up the deficiency that warping function cannot be determined from theoretical analysis,this paper simplifies box girder flange plate into parallel sections that are connected by springs,considering the longitudinal deformation and force of the flange plate of box girder.When the shear lag effect occurs,the flange plate bends.According to the principle of minimum potential energy,the longitudinal displacement function is derived as cosine function by using energy variational method.The longitudinal displacement function is substituted into the shear lag equation,and the bending normal stress equation of simply supported box girder under uniformly distributed load is obtained.To verify the correctness of this method,the flange longitudinal stresses calculated by the proposed method are compared with cubic parabola displacement function calculation values,the measured values and the values calculated by finite element method.The results show that the calculation results of the proposed method match the measured values well,and match the results calculated by cubic parabola displacement function at flange plate basically.Calculation results of the proposed method are in good agreement with the results of the finite element method at the connection of flange and web where there are no measured values.

关 键 词：桥梁工程 翘曲位移函数 能量变分法 剪力滞效应 理论推导 

分 类 号：U448.213[建筑科学—桥梁与隧道工程]