T形肋GFRP抗剪连接件的静载推出试验

Static Push-out Tests for T-type Rib GFRP Shear Connectors

为改善玻璃纤维增强塑料(GFRP)与混凝土的界面粘结性能,进行了3组共计9个T形肋GFRP抗剪连接件的静载推出试验,主要考虑了T形肋内开孔及横向穿孔钢筋2个参数对其抗剪性能的影响,得到了破坏形态、裂缝分布规律及荷载-相对滑移关系,分析了T形肋对GFRP抗剪连接件粘结滑移性能、极限承载力以及破坏机理的影响。基于试验得到的破坏机理建立了T形肋GFRP抗剪连接件的极限承载力计算公式。结果表明:T形肋增加了GFRP抗剪连接件与混凝土的接触面积,提高了界面的粘结力;界面出现滑移后,T形肋孔内的混凝土榫或钢筋混凝土榫能提供更好的抗剪性能;孔内是否配置横向穿孔钢筋将导致试件出现2种不同的破坏形态。

In order to improve the interfacial bond properties between GFRP and concrete, push- out tests were conducted to investigate the mechanical behaviors of nine T-type rib GFRP shear connectors, considering the effects of holes and horizontal perforated steel bars. The failure patterns, crack distribution rules and load-relative slip relationships, were obtained by contrast experiments. The effect of T-type rib on load-slip behaviors, ultimate bearing and damage mechanisms capacities of shear connectors were analyzed. The formulae of ultimate bearing capacity were proposed. The results show that contact surface areas are increased and interracial bond properties between T-type rib GFRP shear connectors and concrete are improved. Concrete tenon or rebar tenon of T-type perfobond rib GFRP shear connectors can provide better shear capacities after interface slipping. Whether the configuring of horizontal perforated steel bars will lead to two different failure patterns.