Fiber-reinforced High-strength Concrete under Elevated Temperature―Effect of Fibers on Residual Properties

摘要

Addition of polypropylene fibers was known to be an effective way in mitigating the explosive spalling failure mechanism, which occasionally happened during heat exposure of high-strength concrete. This paper presents the experimental results on residual properties of fiber-reinforced high-strength concrete under elevated temperature. Some variables being focused on, concerning the effect of fiber on high-strength concrete residual properties, included fiber volume fraction (V_f), fiber length (l_f), and fiber material. Meanwhile, residual properties being observed included compressive strength (f_c), splitting tensile strength (f_t), modulus of elasticity (E), and water permeability coefficient (k). Results from the tests showed that residual properties of polypropylene fiberreinforced high-strength concrete was significantly reduced compared with steel fiberreinforced high-strength concrete, especially in the terms of permeability performance, even though polypropylene fiber was found to be more effective in mitigating explosive spalling.