新型承插型盘扣式模板支撑体系承载力计算方法缺陷分析

对承插型盘扣式模板支撑体系的承载力进行准确预测,有着十分重要的工程意义,但目前普遍采用的承载力计算方法中存在诸多缺陷。根据规范建议方法设计搭建某实际工程承重型高大模板支撑体系。通过现场检测以及有限元模拟分析,探讨承插型盘扣式模板支撑体系的承载力计算方法。在有限元分析中,采用水平力法考虑初始缺陷对承载力的影响,在接头处设置转动刚度值以分析钢管接头处刚度的削弱;并将有限元计算结果与现场实测值对比。结果表明:仅仅采用规范建议的方法进行计算,其结果与实测结果误差较大;考虑初始缺陷和节点半刚性后,结果获得改善;进一步考虑接头转动刚度后,承载力计算结果与实测结果吻合较好。说明在承插型盘扣式模板支撑体系承载力计算中应充分考虑钢管接头处刚度的削弱,以保证施工安全。

Defect Analysis on Calculation Method of Bearing Capacity of the New Socket Button Type Formwork Supporting System

It is of great engineering importance of accurate predicting the bearing capacity of the new socket button type formwork supporting system. However, there are several defects in the calculation method of bearing capacity at present. A practical formwork supporting system was designed and constructed according to the code proposed algorithm. Combined with field test and finite element analysis, calculation methods of socket button type formwork support system carrying capacity were discussion. In finite element simulation, a rotational stiffness value was set at the joint, and the horizontal force method was used to consider the effect of initial imperfection on the bearing capacity. Results were compared with that of field monitoring. It shows that, calculating merely with method proposed by the code leads to large error. Considering initial imperfection and node semi-rigid, results were improved. When joint rotational stiffness was taken into account, calculating results agreed well with monitoring data. In order to ensure construction safety, stiffness weaken at steel tube should be fully considered in the calculation of socket button type formwork supporting system bearing capacity.