摘要
为分析高速铁路跨度40 m双线混凝土简支箱梁桥约束扭转效应,采用薄壁箱梁约束扭转的理论解析法,建立列车活载作用下的约束扭转微分方程,结合ANSYS软件的精细数值模拟结果,对比研究了箱梁在约束扭转下的扭转角、翘曲双力矩、约束扭矩等力学参数的变化规律,研究了腹板倾角、高宽比和悬臂板宽度等计算参数对约束扭转应力的影响规律。结果表明:扭转角在跨中处达到最大,翘曲双力矩在1/4跨、1/2跨处峰值基本一致,约束扭矩在跨中处达到最大值。板壳有限元解与解析解的计算结果存在一定差异,且翘曲正应力在腹板和底板相交处最大相差为66.6%,有限元解更为精确。简支梁跨中截面悬臂端的翘曲效应最明显,翘曲比例系数可达9.16%。翘曲应力总体随高宽比、腹板倾角的增大而减小。
In order to analyze the constrained torsion effect of high-speed railway span 40 m double-line concrete simple box girder bridges,the theoretical analytical method of confined torsion of thin-walled box girders was used.It aimed to establish the constrained torsional differential equation under train live load.Combined with the fine numerical simulation results of ANSYS software,a comparative study of the variation of mechanical parameters,such as torsion angle,warping double moment and restraining torque of box girder under restrained torsion was made.In addition,the effects of calculation parameters were explored,such as aspect ratio,cantilever width and web inclination on constrained torsional stress.The results show that the torsion angle reaches the maximum at the mid-span,the peak of the warping double moment is basically the same at the spot of 1/4 span and the 1/2 span,and the restraining torque reaches the maximum at the mid-span.There are some differences between the calculation results of finite element solutions and analytical solutions of plate and shell elements,and the maximum difference of the warping normal stress at the intersection of the web and the bottom plate is 66.6%,and the finite element solution is more accurate.The warping effect of the cantilever end of the mid-section of the simply supported beam is the most obvious,and the warpage proportional coefficient can reach 9.16%.With the increase of the aspect ratio and the inclination of the web,the overall warping stress decreases.
作者
赵富康
蔺鹏臻
ZHAO Fu-kang;LIN Peng-zhen(Key Laboratory of Road&Bridge and Underground Engineering of Gansu Province,Lanzhou Jiaotong University,Lanzhou 730070,China;Institute of Architecture and Urban Planning,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《科学技术与工程》
北大核心
2020年第25期10472-10479,共8页
Science Technology and Engineering
基金
国家自然科学基金重大项目(11790281)
国家自然科学基金(51878323)
中国铁路总公司科技研究开发计划课题(2017G010-C)。
关键词
混凝土箱梁
约束扭转
有限元法
翘曲应力
concrete box girder
constrained torsion
finite element method
warping stress
