钢筋桁架楼承板-U形钢组合梁 不同抗剪连接方式的受弯性能

为了合理利用在装配式钢结构建筑中应用广泛的钢筋桁架楼承板,将钢筋桁架的下弦钢筋焊接于U形钢梁的上翼缘作为一种新型的抗剪连接件,设计了4根采用钢筋桁架、角钢、栓钉及其组合抗剪连接方式的简支U形钢-混凝土组合梁,并对其进行了静力试验研究和有限元分析,考察了不同抗剪连接方式对其正截面受弯性能的影响.试验结果表明:试件的破坏形态为整体弯曲破坏和端部滑移破坏;仅采用钢筋桁架作为抗剪连接件的试件不能达到完全抗剪连接,可再配置适量栓钉以提高其组合作用;采用钢筋桁架与栓钉作为组合抗剪连接方式的试件的抗剪连接性能优于采用钢筋桁架与角钢作为组合抗剪连接方式的试件.同时运用ABAQUS对试件进行了有限元分析,有限元分析的受弯承载力值与试验值吻合较好.最后在试验研究和有限元分析的基础上,基于全截面塑性理论,提出了完全抗剪连接的钢筋桁架楼承板-U形钢组合梁在正弯矩作用下的受弯承载力计算公式.

Flexural Behavior of U-shaped Steel-concrete Composite Beams with Steel-bars Truss Deck in Different Shear Connectors

To make good use of the widely used steel-bars truss deck in assembled steel structure buildings, the bottom rebar of the steel truss was welded to the upper flange of U-shaped steel beam as a new shear connector in this study, and the experimental study and finite element analysis were conducted on four designed specimens with different shear connectors, i.e. steel truss, angle steel, studs and their combination. The test results showed that the failure modes included bending failure and slip failure; the specimen with steel truss as shear connector can not achieve the full shear connected composite beams, and some studs can be configured to improve its composite action. The shear performance of the specimen with steel truss and stud as combined shear connector was better than that of the specimen with steel truss and angle steel as combined one. Then, finite element analysis was conducted via ABAQUS software, and the ultimate bending capacity of finite element analysis was in good agreement with the ex? perimental one. Based on the experimental and finite element analysis study, a calculation formula of ultimate bend? ing capacity of the U-shaped steel-concrete composite beam with truss deck under positive bending moment was de? rived based on the plasticity theory