爆破移除钢筋混凝土框架柱倒塌性能试验研究

为研究钢筋混凝土空间框架结构的抗倒塌性能,采用爆破方式对一4层2跨2开间的RC框架结构短边中柱和角柱进行了快速移除倒塌试验,通过试验获取了爆破移除框架柱作用过程、结构的动力响应、柱的失效时间和空间空腹梁对荷载分布的影响等数据。试验结果表明:试验框架在快速移除边中柱与角柱后,柱头位移较小,结构没有发生倒塌,处于弹性变形范围。爆炸引起RC框架柱的失效时间约100 ms,结构变形晚于爆炸应力波40 ms左右。在爆破过程中,柱内纵向钢筋在应力波和爆轰气体压力共同作用下向外严重鼓曲变形,对上部结构产生较大的拉伸作用,加大了结构倒塌风险。横向或纵向的空间空腹梁作用是结构在柱失效后的荷载重分布的主要受力机理。

Experimental Study on Collapse-resistant Behavior of RC Frame Structures in Explosion Demolition

To study the collapse-resistant behavior of reinforced concrete space frame structure,the blasting experimental method was adopted to quickly remove the side-column and the corner-column of a 4 layer RC frame structure.The related test data were obtained,including the dynamic response of the frame structure,the impact of failure time and space on load distribution.The results showed that,after rapid removal of the side column and corner posts,the stigma displacement of the test frame was small and the structure didnt collapse with elastic deformation characteristic.Failure time caused by blasting of reinforced concrete frame columns was about 100 ms,and the stress wave from the explosion was earlier 40 ms than the structure failure.The inner column longitudinal reinforcement was removed outwardly seriously on drums deformation under the joint effect of stress wave and explosion gas expansion,which produced a great effect on the upper structure and increased the risk of structural collapse.Vierendeel action of horizontal or vertical space beam were the main mechanical mechanism of inner force distribution after the column failure.