剪力连接度对钢-混凝土组合梁桥力学性能的影响

Influence of Shear Connection Degree on Mechanical Properties of Steel-concrete Composite Girder Bridge

为探究剪力连接度对钢-混凝土组合梁桥力学性能的影响,以某跨径40 m的简支钢-混凝土组合箱梁桥为依托,分析剪力连接度对结构的抗弯承载力、相对滑移和破坏模式的影响。结果表明:当剪力连接度<0.75时,组合梁桥的抗弯承载力与弹塑性阶段的抗弯刚度随剪力连接度的增大而增大,相对滑移随剪力连接度的增大而减小;当剪力连接度≥0.75时,剪力连接度的增加对组合梁桥受力影响较小。调研统计发现,目前国内钢-混凝土组合梁桥剪力连接度的取值较为保守,综合考虑工程结构的受力性能与经济性,建议钢-混凝土组合梁桥剪力连接度的取值范围为0.75~1.25。

In order to investigate the influence of shear connection degree on the mechanical properties of steel-concrete composite girder bridge,the effects of shear connection degree on the flexural bearing capacity,relative sliding and destruction mode of the structure were analyzed based on a simply supported steel-concrete composite box girder bridge with a span of40 m. The results show that when the shear connection degree is less than 0. 75,the flexural bearing capacity and elastic-plastic flexural stiffness of the composite girder bridge increase with the increase of the shear connection degree,and the relative slip decreases with the increase of the shear connection degree. When the shear connection degree is greater than 0. 75,the increase of the shear connection degree has little effect on the stress of the composite girder bridge. Investigation and statistics show that the value of the shear connection degree of steel-concrete composite girder bridges is conservative,considering the mechanical performance and economy of the structure,it is recommended that the value of the shear connection degree of steelconcrete composite girder bridges should range from 0. 75 to 1. 25.