预制混凝土结构插入式预留孔灌浆钢筋锚固性能

Experimental study on plug-in filling hole for steel bar anchorage of the PC structure

为研究预制混凝土结构的钢筋连接方法,设计制作了81个预制混凝土插入式预留孔灌浆钢筋锚固拉拔试件,考虑钢筋直径、混凝土强度、锚固长度等主要影响参数.连续加荷拉拔试验结果表明:灌浆锚固试件的最终破坏状态都是外部钢筋屈服或被拉断,没有发生异常锚固破坏,而且在基本锚固长度基础上分别减小为0.9、0.8倍时还有较大安全储备.根据试验数据结果给出插入式预留孔灌浆钢筋的基本锚固长度为0.8 l a.

To study the connection method between reinforced bars of the precast concrete （PC） structure, 81 plug -in filling hole for lap -joint of steel bar sample tests were made, and the main factors, such as reinforced bar diameter, concrete strength and anchorage length etc. were considered during the tests. The test results indicated that the ultimate failure state of all the anchoring specimens were the external reinforced bar yielding or broken up by pulling, and the abnormal anchorage was not destroyed. When the basic anchoring length was reduced by 10% or even 20%, specimens still showed enough safety. Based on this, the basic anchoring length of plug - in filling hole for lap - joint of steel bar can be given as 0. 8 l a.