内置钢板抗剪连接件方钢管混凝土柱推出试验

Push-out test of square CFST columns with steel plate shear connectors

为了定量化研究带抗剪连接件方钢管混凝土界面的抗剪承载力,设计了10个内壁设置抗剪连接件的方钢管混凝土试件,并进行推出试验,其中9个为钢板条连接件试件,1个为钢筋条连接件对比试件.试验设计参数包括钢管壁厚（宽厚比）、抗剪连接件厚度、抗剪连接件层数、抗剪连接件层间间距及抗剪连接件种类.研究结果表明：钢管宽厚比的降低、连接件厚度的增大均能有效地提高极限承载力及初始刚度;双层连接件试件的极限承载力高于单层连接件试件,极限承载力提高程度与钢板条间距有较大关系;在相等用钢量的情况下,相同层数的钢筋条试件相比较钢板条试件,极限承载力提高了87%,且延性较好;提出的计算方法所得的理论计算值与试验结果较为相符.

In order to quantitatively evaluate the shear-bearing capacity of shear connectors in square concrete-filled steel tube（CFST）,ten push-out tests on square CFST with shear connectors were carried out,including nine steel plate specimens and one steel bar specimen for comparison.Test parameters were width to thickness ratio of steel tube,thickness of shear connectors,the number of shear connector layer and their spacing,and types of shear connectors.The test results demonstrate that,with the decrease of width to thickness ratio of steel tube and the increment of thickness of shear connectors,the ultimate bearing capacity and the elastic stiffness were improved obviously.The ultimate bearing capacity of CFST with double-layer shear connectors was larger than that with single-layer shear connector.And the spacing of steel plate influenced on the degree of improvement.In case of the same steel ratio,the ultimate bearing capacity of steel bar of same layer was 87% larger than the steel plate and exhibited good ductility.The calculated values based on the proposed formula were in good agreement with the test values.