针对高大满堂支撑架在混凝土浇筑期受到水平动荷载作用而产生的结构振动甚至失稳现象进行研究.通过原型试验,研究了在不同混凝土浇筑阶段,顶部受到水平冲击荷载作用下的满堂支撑架的动力性能.考虑在上部结构施工过程中,可能导致的扣件松脱、滑移、断裂甚至失效的情况,研究了不同工况下满堂支撑架的受力性能变化规律.借助有限元仿真分析研究了冲击荷载作用下满堂支撑架的动力反应现象.结果表明,混凝土浇筑过程中,混凝土浇筑量的增加以及剪刀撑的失效将会使得满堂支撑架的自振频率降低,容易引发架体倒塌.当部分立杆节点发生失效时,冲击荷载作用对立杆轴力影响显著增加.
The performance of vibration and instability induced by the horizontal dynamic load in high full hall formwork support during concrete placement were deeply studied.The dynamic behavior of full hall formwork support subjected to horizontal impact load with different concrete pouring amounts was investigated through prototype test.Considering the condition of fastener loosening,sliding,fracture,and even failure in the construction period,the change law of mechanical behavior of full hall formwork support under different working conditions was also found out.Dynamic response of full hall formwork support to impact load was researched through finite element simulation analysis.Based on both the experimental and the analytical results,it can be concluded that the increase of concrete pouring amounts and failure of X-bracing would decrease the frequency of free vibration,which might increase the risk of formwork support collapse.When part of main nodes invalidated,the effect of impact load on post axial force significantly increased.