GFRP-自密实RPC组合试件力学性能试验研究

Experimental study on mechanical performance of GFRP-self-compacting RPC composite specimens

一般纤维增强复合材料(Fiber Reinforced Polymer,FRP)—混凝土组合结构的破坏模式为FRP与混凝土的界面剥离以及自身截面的抗剪承载力不足导致的受剪破坏。为提高FRP—混凝土组合结构的抗剪承载力,开展5根带T型肋玻璃纤维增强复合材料(Glass Fiber Reinforced Polymer,GFRP)板—自密实活性粉末混凝土(Reactive Powder Concrete,RPC)配箍组合试件的试验研究,探讨界面处理、箍筋配置和剪跨比等因素对组合试件受力性能的影响,分别对挠度、应变进行测试,观测裂缝形成与开展过程及其破坏状态等。结果表明,GFRP板的界面粘砂处理和横向贯穿钢筋的配置可以增强GFRP板与混凝土之间的界面抗剪强度,并明显改善两者协同工作性能,提升组合试件的极限变形能力;界面粘砂和配置箍筋能在一定程度上提升组合试件的抗剪承载能力,改善破坏形态;组合试件截面高度越大,承载能力越高,但GFRP材料的利用率会有所降低。

Generally,the failure modes of FRP(Fiber Reinforced Polymer)-concrete composite structures are the interface peeling between FRP and concrete as well as the shear failure caused by insufficient shear bearing capacity of its own cross section.In this study,in order to improve the shear capacity of FRP-concrete composite structure,we tested five GFRP(Glass Fiber Reinforced Polymer)-Self-compacting RPC(Reactive Powder Concrete)stirrup composite specimens with GFRP shaped from multi-T-rib grooves.Discussion with the effects of interface treatment,stirrup configuration,and shear span ratio on composite specimens'mechanical properties.Measured the deflection and strain,respectively,and observed the formation and development process of cracks and their failure state.The results show that the interface sand adhesion treatment of GFRP plate and the arrangement of transverse penetrating reinforcement can enhance the interface shear strength between GFRP plate and concrete,obviously improve the cooperative performance of the two,and enhance the ultimate deformation capacity of composite specimens;the interface sand adhesion and stirrup arrangement can improve the shear bearing capacity of composite slabs and improve the failure mode to a certain extent;the higher the cross section of the specimen,the higher the bearing capacity,but the utilization of GFRP material will be reduced.