提出采用灌芯加固和悬吊加固相结合的方法提高预制空心楼板承载能力,重点讨论了灌浆加固注浆方法、悬吊加固锚固方式、钢丝绳数量不同对加固性能的影响以及钢丝绳的受力状态。进行7块试件在均布荷载作用下的静力试验,其中2块为对比试件,2块为灌浆加固试件,3块为钢丝绳悬吊加固试件。结果表明:钢丝绳悬吊加固使预制空心楼板极限承载力提高45%-74%,极限位移提高175%-195%;从经济性、施工作业量、承载力提高程度以及预应力钢筋的受力情况综合考虑,4根钢丝绳加固效果最佳,越靠近中间的钢丝绳所起作用越大;该方法加固效果显著,可为加固预制空心楼板的实际应用提供一定借鉴。
A method to improve the bearing capacity of precast hollow slab by the combination of grouting core reinforcement and suspension reinforcement was presented. The grouting method of grouting reinforcement, the anchoring mode of suspension reinforcement, the influence of different quantity of steel wire rope on the reinforcement performance and the stress state of steel wire rope were mainly discussed. The static tests of 7 specimens under uniform load were carried out, including 2 contrast specimens, 2 grouting reinforcement specimens, and 3 steel wire rope suspension reinforcement specimens. The results show that steel wire rope suspension reinforcement can improve the ultimate bearing capacity of precast hollow slab by 45 %-74 %, and improve the ultimate displacement by 175%-195%. Considering the economical efficiency, construction work quantity, improvement degree of bearing capacity and the stress of prestressed reinforcement, the reinforcement effect of 4 steel wire ropes is best. The reinforcement effect is greater when the steel wire rope is closer to the middle. The reinforcement effect of the method presented is remarkable, which can be used as reference for the practical application of precast hollow slab reinforcement.