The influence of chloride-sulfate attack history on the residual mechanical properties of concrete after high temperatures

Abstract

Durability studies of basalt fiber reinforced concrete (BFRC) structures are still in their infancy. New breakthroughs are needed in the exploration of the mechanical properties of BFRC under the coupling effect of multiple factors. In order to release the influence of composite chloride-sulfate attack history on the fire resistance of BFRC, mechanical experiments were carried out on BFRC specimens, which were first soaking in a certain concentration of chloride-sulfate composite solution, and then submitted to different high temperatures. The compressive strength, relative dynamic elastic modulus and the residual compressive strength of the specimens after high temperatures were tested. The results show that compared with chloride concentration, sulfate concentration has a greater effect on the compressive strength and relative dynamic elastic modulus of BFRC. The presence of chloride can inhibit the attack of sulfate in the concrete and reduce the change in strength at room temperature. The combined attack of chloride and sulfate aggravates the strength deterioration of the BFRC specimens after high temperatures.