Residual mechanical strength of glass fiber reinforced reactive powder concrete exposed to elevated temperatures

Abstract

Reactive powder concrete (RPC) has a denser microstructure which makes it vulnerable to spalling when exposed to high temperatures. Extraordinary applications of RPC in structures requiring high strength and durability have drawn the attention to explore the behavior of RPC at high temperatures. This research work aims to study the effect of different dosages of glass fibers (GF) on the mechanical performance of RPC after exposure to high temperatures i.e. 200, 400, 600, and 800 °C. Three main mechanical properties were evaluated such as compressive strength, split tensile strength, and flexural strength. Experiments showed that spalling was significantly controlled using the studied dosages of GF i.e. 2–4%. Effect of dosage on residual mechanical properties varied with the changing temperature. Up to 400 °C, RPC with 3%GF showed maximum residual strength properties, whereas, at 600 and 800 °C, RPC with 4% showed maximum residual mechanical strength. The role of fibers in compressive strength was more useful above 400 °C, whereas, flexural strength and split tensile strength were benefited from GF addition at both normal and elevated temperatures.