Bond behavior between corrugated BFRP shell and concrete under monotonic and cyclic loads

Abstract

Abstract This study was aimed at investigating the interface bond behavior of a corrugated basalt fiber-reinforced polymer (BFRP) shell bonded to concrete in a composite bridge deck. The interface between the BFRP shell and concrete was processed by three methods including non-stick sand, stick sand by single-layer adhesive, and stick sand by double-layer adhesive. The bond behavior was evaluated in terms of effective bond length, and strain and stress distributions at the interface. Moreover, the analytical model of the bond stress-slip was obtained by data fitting. For the fatigue bond behavior, the slippage and stress levels with respect to the number of cycles were studied respectively, focusing on interface stick sand by double layer adhesive. The results show that the specimens of stick sand with single-layer adhesive exhibit a 78% higher interfacial fracture energy and much longer effective bond length, compared to those of stick sand with double layer adhesive. The former’s bond behavior was dominated by both chemical adhesion and mechanical interaction force, while the latter’s bond behavior was only affected by chemical adhesion, which was revealed by the stress distribution. Furthermore, the bond stress-slip models exhibit high precision. Under cyclic load, the slip development can be divided into two phases: the rapid development phase from the initial to the 100,000th cycles, and the stable development phase subsequently. In addition, the equation for predicting fatigue life was proposed based on S-N curve.