黏砂变形GFRP筋与约束混凝土之间的黏结性能  

Bond Behavior between Sand-Coated GFRP Rebar and Confined Concrete

作　　者：薛伟辰[1] 王圆[1] 方志庆[1] 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《建筑材料学报》2013年第1期6-11,16,共7页Journal of Building Materials

基　　金：国家自然科学基金资助项目(50978193);国家重点基础研究发展计划(973计划)项目(2012CB026200);交通部西部交通建设科技项目(200631882244)

摘　　要：基于30个Losberg拉拔试验,对黏砂变形GFRP筋与采用箍筋约束的混凝土之间的黏结性能进行了较为系统的研究.研究表明:GFRP筋与约束混凝土之间的黏结-滑移(τ-s)曲线可分为微滑移段、滑移段、下降段、二次上升段以及残余下降段;对于采用箍筋约束的GFRP筋试件,均只发生拔出破坏,而对于无箍筋约束的GFRP筋试件,其破坏模式包括拔出和劈裂两种;与无箍筋约束的GFRP筋试件相比,GFRP筋与约束混凝土之间的黏结强度增加了0%～16%,而达到黏结强度时对应的滑移量则提高了1.20～2.76倍.在考虑GFRP筋直径、黏结长度、体积配箍率等因素的基础上,建立了GFRP筋与约束混凝土之间的黏结-滑移本构模型.Glass fiber reinforced polymer（GFRP） rebar has been most commonly used in civil engineering. Bond behavior of sand-coated GFRP rebar in confined concrete was systematically analyzed. Test results of 30 losberg pullout specimens show that the experimental bond stress-slip curves for GFRP rebar in con fined concrete（r-s curve） is composed of micro-slippage section, slippage section, descending section, sec- ond rising section and residual descending section. For the GFRP rebar specimens in confined concrete, on ly pullout failure occurred, however, the mode of failure of GFRP rebar specimens in unconfined concrete showed pullout failure and splitting failure. The strength of GFRP rebar in confined concrete is 1.00 - 1.16 times that of concrete without stirrups. The slippage of the first peak point in concrete confined by stirrups is 1.20 -2.76 times that of concrete without stirrups. Based on experimental results, the theoreti- cal model of bond stress-slip relationship for GFRP rebar in confined concrete is established.

关 键 词：GFRP筋 约束混凝土 体积配箍率 黏结 黏结-滑移本构模型 

分 类 号：TU377.9[建筑科学—结构工程]