High-Performance Concrete with Polypropylene Microfibers for Fire Safety

This paper presents results from experimental studies on the residual mechanical properties of high-performance concrete reinforced with polypropylene microfibers after exposure to elevated temperatures. A conventional concrete (compressive strength of 25 MPa) and high-performance concretes (compressive strength above 78 MPa) with 1, 2, and 3 kg/m3 additions of polypropylene microfibers were developed. The mixtures were subjected to temperatures of 100, 200, and 300 degrees C for 60 minutes. In the second part of this study, a high-performance concrete with 2 kg/m3 of microfibers was analyzed. Compressive strength, splitting tensile strength, and elastic modulus tests were also performed at 200, 400, and 600 degrees C. Results from the experiments show that polypropylene microfibers were extremely important in minimizing the reduction of compressive strength, where the contents of 2 and 3 kg/m3 were the most effective. Through numerical simulation, it was possible to find the longitudinal elastic modulus and the Poisson's coefficient at each temperature tested.