Abstract
This paper presents experimental results and numerical simulation of direct pull-out tests of basalt fiber reinforced polymer (BFRP) bars embedded in concrete. First, two patches of experimental pull-out tests are briefly descried. In the first experimental patch, the influence of surface texture configuration of BFRP bars on the bonding characteristics between BFRP bars and concrete is investigated through direct pull-out tests carried out on concrete cubes reinforced with BFRP bars. Pull-out test on ribbed steel reinforced concrete cube was also carried out for comparison. In the other experimental patch, pull-out tests were carried out on BFRP bars embedded inside pre-drilled holes into heavy concrete blocks. Through these pull-out tests, the efficiency of two different adhesive materials; namely: epoxy putty and polymer cement, and the effect of cross-section diameter of BFRP bars on the BFRP bar-concrete bond mechanism were investigated. Second, a finite element model (FEM) was employed to analyze the interfacial behavior between BFRP bars and the surrounding materials. Through the FEM, the influence of the tested parameters on the characteristics of local bond-slip models of BFRP bars was assessed by considering different material properties as well as different fracturing bond mechanisms. The experimental and numerical results showed that the bonding behavior of BFRP bars-reinforced concrete structures can be improved by treating the surface texture configurations of BFRP bars. In addition, the properties of the adhesive material between BFRP bars and concrete are key factors controlling the bond mechanism of strengthened concrete structures. Moreover, the proposed FEM was found to be capable of simulating the fracturing bond mechanism of BFRP bars.
