GFRP锚索粘结性能试验研究

Experimental research on bonding properties of GFRP anchor cables

目前在锚索支护工程中常使用的锚筋材料为钢绞线,但钢绞线存在着自重大、不易切割、耐腐蚀性差等问题。GFRP锚索因其具有高强抗拉、耐腐蚀、轻质、易切割等特点,逐渐引起众多专家和学者的注意。因粘结性能作为评价锚固体系好坏的一个重要指标,若采用GFRP锚索代替钢锚索应用于实际工程中,研究GFRP锚索与水泥基体的粘结性能是十分必要的。通过室内拉拔试验,对单根GFRP锚索在不同水泥基材料及多根GFRP锚索在同种水泥基材料中的粘结性能开展研究,研究结果表明:单根GFRP锚索在水泥砂浆中的破坏形式为锚索断裂破坏、单根及多根GFRP锚索在水泥净浆中为试块脆性破坏;单根GFRP锚索在水泥砂浆中的最大粘结强度与极限滑移量均大于在水泥净浆中;在水泥净浆中,GFRP锚索的数量与极限荷载成正比关系,与其最大粘结强度和极限滑移量成反比关系。

At present,the commonly used anchor bar material in anchor cable support engineering is steel strand,but the steel strand has problems such as self-heavy,difficult to cut,and poor corrosion resistance.GFRP anchor cable has gradually attracted the attention of many experts and scholars because of its high strength,tensile strength,corrosion resistance,light weight and easy cutting.Because the bonding performance is an important index to evaluate the quality of the anchor system,it is necessary to study the bonding performance of the GFRP anchor cable and the cement matrix if the GFRP anchor cable is used instead of the steel anchor cable in practical engineering.In this paper,the adhesion performance of a single GFRP anchor cable in different cement-based materials and multiple GFRP anchor cables in the same cement-based material is studied through indoor pull-out tests.The results show that:a single GFRP anchor cable in cement mortar The failure mode of the GFRP anchor cable is the fracture failure of the anchor cable,and the single and multiple GFRP anchor cables in the cement slurry are the brittle failure of the test block;the maximum bond strength and ultimate slip of a single GFRP anchor cable in the cement mortar are greater than In the cement paste;in the cement paste,the number of GFRP anchor cables is proportional to the ultimate load,and inversely proportional to its maximum bond strength and ultimate slip.