Bond Behavior of GFRP Bar in both Normal and Lightweight Aggregate Concrete

摘要

Interfacial bond stress-slip between the concrete and longitudinal reinforcement always occurs in reinforced concrete (RC) members. The bond strength in lightweight concrete, with or without transverse reinforcement, is lower than in normal weight concrete. In this paper, bond strength and behavior of Glass Fiber Reinforced Polymer (GFRP) rebar and lightweight concrete were experimentally investigated and compared with normal aggregate concrete. Comparison of normal and lightweight aggregate concrete, in order to find better uptake of aggregate effect on bond behavior of GFRP bars was studied. Two mix designs of structural lightweight concrete with expanded clay aggregate and one mix design of high strength concrete with normal aggregate are prepared for this study. Two sizes of GFRP rebar are used to study effect of bar size in bond behavior of lightweight concrete. Upshots of current study guide us to this fact that bond strength is affected by rebar size, cement content and finally, the compressive strength of concrete. While general poor behavior of GFRP in lightweight concrete should be taken into consideration. Decrease of bar size has considerably effect on bond improvement in structural lightweight aggregate concrete.