考虑约束扭转二次剪力流影响的箱梁畸变效应分析  

Analysis on distortion effect of box girders considering the secondary shear flow due to restrained torsion

作　　者：王晨光[1] 张元海[1] Wang Chenguang;Zhang Yuanhai(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学土木工程学院,兰州730070

出　　处：《东南大学学报（自然科学版）》2024年第4期937-943,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51968040,52368020)。

摘　　要：为了揭示箱梁约束扭转和畸变之间的耦联关系,研究约束扭转对箱梁畸变效应的影响,根据约束扭转二次剪力流形成的畸变荷载,建立了考虑约束扭转的箱梁畸变控制微分方程.基于乌曼斯基第二理论,提出约束扭转剪力流是基于约束扭转引起的畸变效应修正后的总扭矩布雷特剪力流,并通过Ansys有限元模型和能量法计算结果对理论公式进行了验证.数值算例结果表明:2种不同约束扭转剪力流分解方法计算所得结果完全一致;不同计算点处的约束扭转剪应力与Ansys有限元法计算结果吻合良好;扭转畸变翘曲总正应力、畸变翘曲正应力均与按能量法计算所得结果吻合良好,误差不超过10%.计入约束扭转二次剪应力的影响能够更准确地计算箱梁畸变效应.To reveal the coupled relationship between restrained torsion and distortion of the box girders and study the influence of restrained torsion on the distortion effects,the governed differential equation for distortion of box girders considering the restrained torsion is established based on the distortion load induced by the secondary torsional shear flow due to restrained torsion.According to Umansky's second theory,the restrained torsional shear flow is proposed to represent the Bredt shear flow of total torque corrected by the distortion effects induced by restrained torsion.The formulas are validated using numerical results from Ansys finite element models and the energy method.Numerical results indicate that the results obtained from the two decomposition methods of restrained torsional shear flow are identical.The restrained torsional shear stresses at different points agree well with the results calculated by the Ansys finite element method.The total normal stresses induced by torsion and distortion and the distortion normal stresses agree with the results obtained from the energy method calculation,with errors not exceeding 10%.It is more accurate to calculate the distortion effects in box girders considering the influence of secondary shear stress due to restrained torsion.

关 键 词：箱梁 约束扭转 畸变效应 耦联分析 

分 类 号：U448.213[建筑科学—桥梁与隧道工程]