采用高强度螺栓连接件的钢-混凝土组合梁力学性能研究

RESEARCH ON MECHANICAL PROPERTIES OF STEEL-CONCRETE COMPOSITE BEAMS WITH HIGH-STRENGTH BOLT CONNECTORS

为研究高强度螺栓作为抗剪连接件的钢-混凝土组合梁力学性能,通过改变高强螺栓的布置间距,对4根组合梁试件进行单点静力加载。由试验得到荷载-挠度曲线、荷载-滑移曲线和沿截面高度的应变分布曲线,进而分析端部螺栓间距和预紧力两个变量对组合梁抗弯承载力、初始刚度、横截面应变分布的影响。试验结果表明:集中荷载作用下,试验梁为典型弯曲破坏;减小端部螺栓布置间距可以提高组合梁的承载力及初始刚度;而提高预紧力也可提高组合梁初始刚度,但对极限承载力影响较小。

In order to study the mechanical properties of steel-concrete composite beams with high-strength bolt connectors,single-point static loading was conducted on 4 composite beam specimens by changing the pre-tightening forces of high-strength bolts and the spacing of end bolts.The load-deflection curve,the load-slip curve and the strain curve along the height of the section were obtained from the experiment,and then the influence of the two variables on the flexural bearing capacity,initial stiffness and cross-sectional strain of the composite beam was analyzed.The test results showed that the test beam subjected to concentrated loads was typical bending failure,reducing the spacing of the end bolts could improve the bearing capacity and initial stiffness of the composite beam and increasing the pre-tightening force could also increase the initial stiffness of the composite beam,but had little effect on the ultimate bearing capacity.