网架结构连续倒塌性能的试验研究

Experimental Study on Progressive Collapse of Space Grid Structures

进行了跨度为1.25 m、5×5网格、网格尺寸0.25 m×0.25 m、高度0.175 m的四角锥网架结构模型的连续倒塌试验,研究网架结构受力最大的腹杆初始失效后,网架结构其余杆件受力变化及结构的连续倒塌全过程,观测杆件的荷载-应力曲线、荷载-位移曲线,分析网架结构连续倒塌的性能和特点。网架结构的连续倒塌主要是由受压杆件的屈曲失稳引起的,破坏比较突然。

The aim of the experiment was to investigate the progressive collapse performance of a square pyramidal grid structure,which was designed with 1.25 m span,5×5 grid and 0.175 m height.The ventral bar with the maxim force was cut to simulate its failure,and the force change in the rest bars and the whole process of progressive collapse were observed.The load-strain curve and the load-displacement curve were also recorded.Based on the experiment,the properties of progressive collapse of space grid structure were analyzed.The initial local damage of the ventral bar would lead to progressive collapse of space grid structure.