变刚度组合连续梁有效宽度研究  

Research on Effective Width of Composite Continuous Girder with Variable Stiffness

作　　者：温宗意 肖林[1] 张永琦 卫星[1] 任万敏[2] WEN Zongyi;XIAO Lin;ZHANG Yongqi;WEI Xing;REN Wanmin(School of Civil Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu Sichuan 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中铁二院工程集团有限责任公司,四川成都610031

出　　处：《中国铁道科学》2022年第4期1-8,共8页China Railway Science

基　　金：国家自然科学基金资助项目(52078424)。

摘　　要：为研究变刚度组合连续梁的有效宽度,采用有限元软件AnsysAPDL建立3跨变刚度组合连续梁空间有限元模型,计算组合梁关键截面混凝土板的有效宽度和纵向应力分布,进行4种常用中外规范的适用性评估,以及变刚度区域底板混凝土构造和钢与混凝土界面的抗剪刚度对混凝土顶板有效宽度和纵向应力分布的影响分析。结果表明:在边跨跨中截面和中跨支座截面,用英国规范和日本规范计算出的混凝土顶板有效宽度与有限元的计算结果较为吻合,差距在15%以内;在中跨支座附近的变刚度段内,底板的栓钉抗剪刚度变化只对中跨截面顶板的有效宽度有影响;全桥栓钉的抗剪刚度退化至0.1倍初始刚度之前,对顶板的有效宽度和纵向应力分布影响较小,变化在5%以内;当各关键截面栓钉抗剪刚度分别降低时,仅相应截面处的有效宽度和顶板纵向应力分布受影响,相同退化条件下,支座截面受影响最大。The finite element software ANSYS APDL was used to establish the spatial finite element models of the three-span composite continuous girders with variable stiffness,in order to study the effective width of the girder.The distribution of longitudinal stress and effective width of the concrete slab on the critical section of the composite girder were calculated for the adaptability assessments of four commonly used domestic and foreign standards.The influences of the construction of the bottom concrete slab in the region with variable stiffness and of the shear stiffness of the steel-concrete interface on the effective width and the distribution of longitudinal stress of the top concrete slab were analyzed.Results show that the effective widths of the top concrete slabs on the mid-span section in the side span and the support section of the mid-span calculated by British and Japanese standards and the results calculated by finite element reveal a relatively high degree of consistency with the difference remaining within 15%.In the section with variable stiffness around the mid-span support,the shear stiffness variation of the stud of the bottom concrete slab only affects the effective width of the top slab in the mid-span section.Before the shear stiffness of the whole-bridge studs degenerates to 0.1 times the initial stiffness,it has little influence on the effective width and the distribution of the longitudinal stress,with variation ranging within 5%.When the shear stiffness of studs in each critical section degrades respectively,only the effective width at the corresponding section and the longitudinal stress distribution of the top slab are affected,and the support section is most affected under the same degraded situation.

关 键 词：组合连续梁 变刚度 有效宽度 纵向应力 抗剪刚度 刚度退化 有限元 

分 类 号：U441[建筑科学—桥梁与隧道工程]