胶合木-钢夹板螺栓连接滞回性能试验

【目的】为探明胶合木-钢夹板螺栓连接的动力性能和抗震性能,确保连接件在车辆、机械振动等动力荷载下的可靠性。【方法】针对胶合木-钢夹板螺栓连接的构造特点,考虑胶合木厚度和螺栓直径之比(厚径比)、螺栓顺纹间距、螺栓并列和错列布置方式等参数的影响,设计制作了4类13组共39个胶合木-钢夹板螺栓连接件,在低周反复荷载作用下进行滞回性能试验。【结果】试验结果表明:在单螺栓连接中,连接部位的破坏模式逐渐由"螺栓刚直"向"双铰"转化,胶合木销槽破坏模式逐渐由销槽整体承压破坏向两端部挤压破坏转变,试件滞回曲线基本都呈现饱满的弓形和棱形,具有良好的耗能能力和抗震性能,但其承载能力较低。在多螺栓连接中,螺栓和胶合木的破坏模式分别以"双铰"破坏和销槽端部挤压破坏为主,试件滞回曲线均呈现饱满棱形,该类试件在承载能力、抗震性能和耗能能力上均有大幅提升;随着螺栓顺纹间距的增大,试件的承载能力不断增大,但螺栓顺纹间距在200 mm时,极限荷载增幅趋于平缓,初始刚度增涨大幅放缓,且整体刚度退化与螺栓顺纹间距为250 mm时基本相同;螺栓并列布置滞回曲线饱满程度好于错列布置;螺栓双排布置承载能力比单排布置的承载能力更高,刚度退化更小。【结论】胶合木-钢夹板螺栓连接具有较好的耗能能力、抗震性能及延性性能;螺栓顺纹间距在200 mm时,抗震性能最佳;螺栓错列布置的抗震性能比并列要好,螺栓双排布置的抗震性能更优越。

Experiment on hysteretic behavior of steel splint bolted connections for glulam

【Objective】In order to investigate the dynamic and seismic performance of glulam steel splint bolt connection,and ensure the reliability of the connector under dynamic loads such as vehicle and mechanical vibration.【Method】According to the structural characteristics of steel plywood bolted connections for glulam,considering the influence of the ratio of glued wood thickness to bolt diameter(thickness diameter ratio),bolt spacing along the grain,bolt staggered arrangement and other parameters,39 glued wood steel splint bolt connections in 13 groups of 4 categories were designed and manufactured,and the hysteretic performance test was carried out under the low cycle repeated load.【Result】The test results show that in the single bolt connection,the failure mode of the joint gradually changes from“bolt rigid”to“double hinge”,and the failure mode of the glulam pin groove gradually changes from the overall bearing failure of the pin groove to the compression failure of the two ends.The hysteretic curve of the test piece basically presents full bow and prism,with good energy consumption and seismic performance,but its bearing capacity is relatively low.In the multi bolt connection,the failure modes of bolt and glulam are“double hinge”failure and compression failure at the end of pin groove,respectively.The hysteretic curves of the test pieces show full prismatic shape,which greatly improves the bearing capacity,seismic performance and energy consumption capacity of the test pieces.With the increase of the bolt parallel spacing,the bearing capacity of the test pieces increases,but the bolt parallel spacing is 200 mm,the increase rate of ultimate load tends to be gentle,and the increase rate of initial stiffness slows down significantly,and the entirety degradation of stiffness is basically the same as that of the bolt with a straight line of 250 mm;the fullness of hysteretic curve of bolt arranged in parallel is better than that of staggered arrangement;the bearing capacity of bolt arranged in double rows is higher than that of single row,and the degradation of stiffness is smaller.【Conclusion】Glued wood steel plywood bolted connection has better energy dissipation capacity,seismic performance and ductility performance;when the bolt spacing along the grain is 200 mm,the seismic performance is the best;the seismic performance of members arranged in staggered rows with bolts is better than that of members arranged in parallel,and the seismic performance of members arranged in double rows with bolts is better.