扣件式钢管满堂脚手架整体稳定试验与有限元分析

通过7个模型静力试验，分析了均布荷载作用下超高扣件式钢管满堂脚手架的失稳机理和破坏模式，以及顶层杆件扣件连接方式、立杆步距、扣件拧紧力矩、非加载区域等参数对满堂脚手架极限荷载的影响。通过与采用JGJ 130-2011《建筑施工扣件式钢管脚手架安全技术规范》中满堂脚手架承载力计算公式的计算结果对比，发现试验值是规范公式计算值的1.56~3.75倍，表明规范计算公式偏于保守。建立考虑扣件半刚性和杆件初弯曲的有限元分析模型，其分析结果与试验结果吻合较好，证明了有限元方法可精确预测扣件式满堂脚手架的承载力和破坏模式。根据有限元分析获得的顶层扣件连接摩擦力的分布规律，建议满堂脚手架顶层扣件抗滑承载力计算的不均匀系数取值1.51。

Experimental research and FEA on bearing capacity of full hallsteel tube and coupler scaffold support system

Through seven prototype testing, the failure mechanism of full hall steel tube and coupler scaffold was analyzed under uniform loading condition.The influences of post height, upper member connection, non-loading area and the tightening torque of coupler on the ultimate bearing capacity of the full hall steel tube and coupler scaffold were studied. Compared with the results calculated according to the code JGJ 130—2011 ‘Technical code for safety of steel tubular scaffold with couplers in construction’, it is found that the calculation values are 1.56-3.75 times higher than the corresponding test values, indicating that the calculation method in current code is extremely conservative. A numerical analysis method, which can consider the effect of semi-rigid property of coupler and initial curvature of steel tubes, is presented and verified by tests. Based on the FE analysis result, the distribution of friction forces in upper coupler connection was analyzed, and a non-uniform coefficient with value 1.51 was presented to consider the inhomogeneity in the future design of upper coupler connection.