基于剪切变形规律的PC箱梁剪力滞效应研究  

Research on shear lag effect of PC box girder based on shear deformation law

作　　者：时元绪 李体翰 SHI Yuanxu;LI Tihan(Shanghai Municipal Engineering Design Institute(Group)Company Limited,Shanghai 200092,China)

机构地区：[1]上海市政工程设计研究总院(集团)有限公司,上海200092

出　　处：《山东理工大学学报（自然科学版）》2024年第5期12-18,共7页Journal of Shandong University of Technology:Natural Science Edition

摘　　要：箱梁配筋后截面刚度的变化不仅对翼缘板纵向正应力产生影响,而且对翼缘板中的剪力流分布规律也产生影响。基于换算截面法,提出利用翼缘板剪切变形规律修正PC箱梁剪力滞翘曲位移函数。采用能量变分原理,引入修正系数对配筋后的箱梁悬臂板、底板的剪切转角最大差值进行修正,并将修正后的翘曲位移函数代入剪滞变分方程。为验证计算公式的正确性,将采用推导公式计算的翼缘板应力值与实体有限元计算值进行对比分析,结果表明计算结果与实体有限元结果误差基本在5%以内。本文得出了不同配筋率对剪力滞效应的影响,提供了一种计算PC箱梁不同翼缘板尺寸剪力滞翘曲位移函数的简便方法。The change of section stiffness of the box girder after reinforcement not only affects the longitudinal normal stress of the flange plate,but also affects the distribution of shear flow in the flange plate.Based on the conversion section method,it is proposed to use the shear deformation law of flange plates to correct the shear lag and warping displacement function of PC box beams.Based on the energy variational principle,a correction coefficient is introduced to correct the maximum difference between the shear angle of the reinforced cantilever plate and the bottom plate of the box girder,and the modified warping displacement function is substituted into the shear lag variational equation.To verify the correctness of the calculation formula,the stress value of the flange plate calculated from the derived formula is compared and analyzed with the calculated value of the solid finite element method.The research results indicate that the error between the calculation results and the solid finite element results is basically within 5%,and the influence of different reinforcement ratios on the shear lag effect is obtained.This study provides a simple method for calculating the shear lag warping displacement function of PC box beams with different flange plate sizes.

关 键 词：桥梁工程 配筋 剪力滞效应 翘曲位移函数 有限元 

分 类 号：U441[建筑科学—桥梁与隧道工程]