高大模板扣件式钢管支撑系统整体受力性能研究

采用有限元软件ABAQUS对高大模板扣件式钢管支撑系统的整体受力性能进行分析，利用弹簧单元模拟扣件的半刚性连接，通过屈曲分析得到的屈曲模态施加初始缺陷，并将有限元计算结果与3个工程项目的实测结果进行对比，验证有限元模型的准确性。在此基础上，利用有限元软件对高大模板扣件式钢管支撑系统的稳定承载力进行参数分析，分析的参数包括扣件拧紧扭力矩、支撑高度、横杆步距、立杆纵距、立杆横距、初始缺陷等，得到了各因素对其整体稳定承载力的影响规律。参数分析结果表明：横杆步距、立杆横距、初始缺陷对高大模板支撑系统稳定承载力影响显著，随着横杆步距、立杆横距、模态比例因子的增加，稳定承载力迅速减少。通过调整立杆的计算长度系数，将高大模板扣件式钢管支撑的整体稳定承载力计算等效为一根立杆的稳定承载力计算，并提出计算长度修正系数的简化设计公式，为工程人员的运用提供参考。

Study on the overall stability of high and large formwork support system with fastening style steel pipe

The overall stability of high and large formwork support systems with fastening style steel pipe was analyzed by finite element software ABAQUS. The semi-rigid connection relationship of fasteners was simulated by the spring element and the initial defects were applied by the buckling mode. By comparing the finite element calculation results and the measured results at three engineering projects, the accuracy of the finite element model was verified. The influence of some parameters, such as fastener tighten torque, support height, cross rod drawing space, vertical rod longitudinal space, vertical rod transverse space and the initial defect, was analyzed. The results show that the cross rod drawing space, vertical rod transverse space as well as the initial defect have significant effects on the overall stability bearing capacity of high and large formwork support systems with fastening style steel pipe. The bearing capacity decreases quickly with the increase of cross rod drawing space, vertical rod transverse space and scale factor of buckling mode. By adjusting the calculated length coefficient of vertical rod, the analysis model for the overall stability bearing capacity can be simplified as a vertical rod. In the end, a simplified formula for the calculation length coefficient is put forward, which can provide reference for the engineering application.