扣件式钢管模板支架稳定性试验研究

EXPERIMENTAL STUDY ON STABILITY OF COUPLER STEEL TUBE FALSEWORK

为研究扣件式钢管模板支架的力学性能,对模板支架空间结构体系进行一系列足尺试验研究,得到不同工况下模板支架的极限承载力、破坏模式及顶层节点的荷载-位移曲线。可以看出:5个工况中,工况1因未设置剪刀撑而使其承载力最小;由于步距的减小,工况4的稳定承载力较工况3提高13.8%;而横距的减小,使工况5的稳定承载力较工况4提高3%;模板支架的失稳属整体失稳,剪刀撑的布置对其失稳模式有着重要的影响,在后续的研究中,尚需确定模板支架的标准构造,然后对其开展一系列的试验和理论研究;模板支架属于钢结构范畴,建议在设计计算时,采用有侧移框架理论并考虑节点的半刚性对其进行设计计算。

To study mechanical properties of coupler steel pipe falsework, it was conducted a series of full-scale researches on the spatial structure of the falsework, and it was obtained that the ultimate bearing capacity of the falsework under different conditions, the destruction pattern and the load - displacement curve of the top-level node. It can be seen that in the 5 working conditions, the working condition 1 without cross bridging causes its supporting capacity to be the smallest; a reduction of step pitch, makes the bearing capacity of condition 4 increase by 13.8% as compared with working eonditioli 3, but the reduction of the horizontal distance makes stability of working condition 5 enhance by 3% than that of working condition 4. Instability of the falsework belongs to the overall instability, the arrangement of the bridging to the support has an important influence to its instability mode, in the following researches, it still need to determine the standard structure of the falsework and then carries out a series of experiments and the fundamental researches on it. The falsework belongs to the steel structure category, it is suggested that when designing and calculating, the sway frames theory should be used and the semi-rigid node should be considered.