摘要
以薄壁箱梁的弯曲理论为基础,从分析微板剪力流出发,结合弹性理论中求解平面应力问题的假设,推导考虑薄壁箱梁各板面内剪切效应时的弯曲纵向位移函数,同时从理论上导出剪力滞翘曲位移函数。运用能量变分原理及铁木辛柯深梁理论的假设简化并求解考虑各板面内剪切效应的纵向位移函数,并给出数值算例。研究结果表明:按本文推导的考虑各板面内剪切效应的位移函数计算的简支梁跨中截面正应力与实测值及有限元值吻合良好,剪应力与挠度较以往方式求解的结果更为准确,且箱梁挠度及腹板剪应力计算值相对于初等梁的结果均有明显增加,最大增量达到21%。
On the basis of the bending theory of thin-walled box girders, and in combination with the hypothesis for solving plane stress problems in elasticity theory, bending longitudinal displacement function considering each plate in-plane shear effect of thin-walled box girders was derived. At the same time, the shear lag warping displacement function was derived theoretically. The displacement mode considering in-plane shear effect of all plates was simplified and solved by using the principle of energy variation and Timoshenko hypothesis of deep beam theory, and the numerical example was given. The results show that the calculated stresses at mid-span cross section of a simply supported box girder by using the displacement mode with shear effect are in a good agreement with the measured values and the finite element analysis results. There are large differences between the calculated shear stresses which considering all plates’ shear effect and the traditional calculation results. Compared with previous methods, the shear stress and deflection calculated in this research are more accurate; what’s more, the shear stress of webs and deflection of the box girder increases, the biggest growth reaches 21%.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2015年第10期3928-3935,共8页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(51268029
51068018
51468032)~~
关键词
薄壁箱梁
面内剪切效应
能量变分法
挠度
剪力流
thin-walled box girder
in-plane shear effect
energy variation method
deflection
shear flow
