基于扣件式脚手架下半刚性连接对GFRP圆管弯曲承载能力的影响研究

Study on Influence of Semi-rigid Connection on Bending Capacity of GFRP Tube Based on the Fastener Scaffold

制作玻璃纤维增强塑料(GFRP)圆管脚手架时,横杆承担来自施工人员和设备等荷载。由于扣件与GFRP圆管连接的节点为半刚性,因此研究半刚性连接对GFRP圆管弯曲承载能力的影响具有重要意义。首先对不同跨距和不同扣件预紧扭矩下的GFRP圆管进行弯曲试验,得出GFRP圆管在不同条件下的弯曲承载力;其次建立有限元模型,分别对GFRP圆管在铰接、半刚性连接和刚接下的弯曲承载力进行研究,并与试验结果进行对比。研究表明,GFRP圆管在半刚性连接下弯曲承载能力介于铰接与刚接之间,并且转动刚度在16.84~71.27 kN·m/rad范围时,转动刚度的变化对GFRP圆管弯曲承载力影响较小。

Fabrication of glass fiber reinforced polymer(GFRP)tubular scaffolds should consider the cross bars could bear the weight of construction workers,equipment and other loads.In light of the semi-rigid connection between fasteners and GFRP tubes,it was necessary to study the impact of such semi-rigid connection on bending and load capacity of GFRP tubes.Firstly,the different spans and different pre-tensions of fasteners for GFRP tubes were tested by bending test,and bending and load capacity of GFRP tubes under different conditions were obtained.Secondly,a finite element model to study bending and load capacities of the GFRP tubes under hinged connection,semi-rigid connection and rigid connection was established,and then compared these test results.The study shows that the bending and load capacity of the GFRP tubes under semi-rigid connection is between that of hinged and rigid connections,and the change of torsional rigidity has the least impact on the bending and load capacity of GFRP tubes,when the torsional rigidity is between 16.84 and 71.27 kN·m/rad.