装配式组合结构柱高强钢管连接节点界面黏结性能试验

Interfacial Bond Performance Experiment on High-Strength Steel Pipe Joints for Prefabricated Composite Structural Columns

为确定装配式组合结构柱高强钢管连接节点常用的φ114×25、φ152×16和φ194×10截面规格Q420连接钢管的黏结长度及构造,开展了在不同黏结长度(600 mm、800 mm)、不同黏结材料(C35混凝土、M50灌浆料)及钢管外壁增设φ6@50螺旋筋条件下的钢管推出试验。通过对比分析荷载-位移/滑移曲线及黏结强度,探讨钢管连接节点的界面黏结性能。试验及分析结果表明,600 mm黏结长度即可保证节点具备满足相关规范要求的黏结强度,黏结长度增大可延缓滑移,但黏结强度随之降低;高强度灌浆料明显提高峰值点荷载大小,对曲线走势无明显影响;长细比与径厚比影响规律不明显;条件相同的情况下φ114×25截面钢管可获得较高的黏结强度;螺旋筋可有效提高黏结强度,延缓界面滑移,且施工简便,建议采用。

To determine the bond length and configuration of high-strength Q420 steel pipe joint for prefabricated composite structural columns,including the pipe sections ofϕ114×25,ϕ152×16 andϕ194×10,push-out tests were conducted.The different bond lengths(600 mm and 800 mm),different bond materials(C35 concrete and M50 grout)and the setting of spiral rebarsϕ6@50 were considered.By comparing and analyzing the load displacement/slippage curves as well as bond strengths,the interfacial bond performance of steel pipe joints was discussed.The test and analysis results showed that 600 mm bond length could ensure that the joint had bond strength that could meet the requirements of the specification.The increase of bond length could delay the slip,but the bond strength decreased.The high-strength grout obviously increased the peak load,and had no obvious effect on the trend of the curve.The influence of slenderness ratio and diameter thickness ratio were not obvious.Under the same conditions,ϕ114×25 steel pipe could obtain the highest bond strength.Spiral rebars could effectively improve the bond strength and delay the interface slip,which should be recommended in engineering,due to its good behavior and easy construction.