不同板中配筋形式下板柱结构的连续倒塌性能

Progressive Collapse Performance of Flat Slab Structures with Different Slab Reinforcement Details

在爆炸、冲击等偶然荷载作用下,钢筋混凝土(RC)板柱结构中承重柱失效可能导致结构发生局部或整体连续倒塌破坏.为了研究板中配筋形式对RC板柱结构抗连续倒塌性能的影响,制作了2个1/3比例的板柱子结构模型,通过单调静力加载试验研究了角柱缺失条件下结构的连续倒塌性能.试验研究表明:在混凝土板内配置连续上层钢筋可以有效减小板上裂缝的宽度;与板中采用非连续上层配筋的试件相比,采用连续配筋试件的屈服荷载、第一个峰值荷载和极限承载力分别提高了38.4%、31.8%和7.5%,在动力荷载作用下试件的抗倒塌能力也得到了明显提高;板中拉膜效应对于塑性铰线机制失效后结构的抗倒塌承载力贡献显著.

The local or global progressive collapse of reinforced concrete （RC） flat slab structures may occur due to the failure of load-bearing columns under accidental loading, such as explosion and impact. In order to investigate the effect of slab reinforcement details on the progressive collapse performance of RC flat slab structures, two one- third scale RC flat slab substructure models are constructed and tested under monotonic static load in the scenario of loss of a corner column. Experimental results show that （ 1 ） continuous top slab reinforcement can effectively re- duce the width of cracks on the slab; （2） as compared with the specimen with discontinuous top slab reinforce- ment, the yield load, first peak load and uhimate bearing capacity of the substructure with continuous top slab rein- forcement increase respectively by 38.4% , 31.8% and 7.5% , and the progressive collapse resistance under dy- namic load is significantly improved as well; and （3） the tensile membrane action in the slabs contributes signifi- cantly to the progressive collapse resistance after the working mechanism of yield lines fails.