承插型盘扣式钢管支架盘扣节点抗扭刚度影响因素

Influence Factor of the Disk-pin Joint Node Torsional Stiffness of the Disk Lock Steel Tubular Scaffold

承插型盘扣式钢管支架盘扣节点属于半刚性连接,其抗扭刚度是架体结构稳定承载力的重要影响因素。为保证承插型盘扣式钢管支架设计安全可靠和经济合理,对架体盘扣节点抗扭刚度影响因素进行研究,揭示各影响因素对盘扣节点抗扭刚度的作用机理,提出合理的抗扭刚度值。在盘扣节点抗扭试验的基础上,分析得盘扣节点扭矩-转角关系曲线和抗扭刚度影响因素,建立盘扣节点实体有限元模型对影响因素进行数值分析,提出合理的盘扣节点抗扭刚度建议值,并通过架体压载试验和有限元数值分析的结果对比,验证节点抗扭刚度建议值的合理性。研究结果表明:插销与连接盘的接触面积和材料应变硬化模量对盘扣节点抗扭刚度影响较大;盘扣节点扭矩与转角关系曲线非线性特性明显,抗扭刚度分3个阶段进行选取较为合理,各阶段盘扣节点抗扭刚度值宜取50~60、20~25、0~5 kN·m/rad。

The disk-pin joint node of disk lock steel tubular scaffold is a semi-rigid connection,and its torsional stiffness is an important influence factor on the stability bearing capacity of the frame structure.In order to ensure the safety,reliability,economy and rationality of the designed disk lock steel tubular scaffold,the influence factors of the torsional stiffness of the disk-pin joint node were studied,the mechanism of which was revealed.The reasonable value of the torsional stiffness was put forward.Based on the torsion test of the disk-pin joint node,the torque-rotation curve and the influence factors of the torsional stiffness were obtained.Then the 3-D finite element model of the disk-pin joint node was established to analyze the influence factors numerically,and the reasonable recommended values of the torsional stiffness of the disk-pin joint node were proposed.By comparing the results of the frame load test and the finite element numerical analysis,the rationality of the recommended torsional stiffness of the disk-pin joint nod was verified.It is pointed that the effects of the contact area between wedge and disk plate and the strain hardening modulus on the torsional stiffness of the disk-pin joint node are remarkable.The nonlinear characteristic of the curve between the torque and the rotation angle of the disk-pin joint node is obvious.It is reasonable to select the torsional stiffness in three stages.The values of the torsional stiffness of the disk-pin joint nod in each stage should be 50~60,20~25 and 0~5 kN·m/rad.