超高模板支撑体系稳定承载力研究及内力实测分析

Stable bearing capability of super-high supporting framework and the analysis of the interior stress measurement

在直角扣件节点刚度试验的基础上,结合现场实测对抗扭刚度进行了统计分析。在此基础上采用特征值屈曲分析及非线性屈曲分析两种方法,分别研究了不同节点连接方式、初始缺陷及搭设高度对超高模板支撑体系稳定承载力的影响。对搭设高度为20.4m的超高模板支撑体系进行了内力静态实测,将结果同8.7m高架体内力实测结果进行了对比。结果表明:节点处初始扭转刚度的建议值为35kN.m/rad;节点半刚性、架体初始缺陷、架体搭设高度对超高模板支撑体系稳定承载力影响较大;超高模板支撑体系内部立杆的偏压将导致杆件应力呈波纹状变化。

The present article is aimed to introduce our study of the stable bearing capability of the supra-high supporting framework and the analysis of the interior stress measurement.While studying the relation between the tightening torque and the torsional stiffness of the right angle coupler in the steel scaffold with fasteners,we have done the joint stiffness test of the coupler,in which we have applied different tightening torques to the different right-angle couplers.And,then,we have studied and recorded the relationship between the rotary angle and the rotary force with different forces acted on the right-angle coupler.While proceeding with our tests,we have chosen the model M=nln（1＋θRk/n） to conduct our regression analysis.According to the results of our regression analysis,we have determined the relation between the tightening torque and the torsional stiffness of the right-angle coupler,which makes it possible for us to identify the initial torsional stiffness of right angle coupler on the basis of our statistical analysis of the fastener＇s tightening torque.Relying on the data of the torsional rigidity we have gained,we have worked out the stable carrying capacity of supra-high supporting system for the formwork in different joints,with initial defects and erection of height accounted through the eigenvalue buckling analysis and the nonlinear buckling analysis.And then,compare the stress of the two different supporting systems of the formwork while concrete is being poured.The results show that in order to make the supporting system for the formwork highly stable,it is recommended to choose 35 kN·m/rad as the value of the initial torsional stiffness.While choosing the semi-rigid joints,it is necessary to detect the initial defects and increase the height because the initial defects tend to have a strong impact on the stable carrying capacity of super high supports of the formwork.Thus,it can be seen that the present research would make a lot of sense to the technicians who are engaged in architecture affairs.It helps them to understand the stable capability of the super high supports for the formwork and in turn help them to enhance the safety and security in their construction jobs with well-prepare measures.