Research on High- Temperature Damage of Basalt Fiber Lightweight Aggregate Concrete

Abstract

To investigate the variation laws of the mechanical properties of basalt fiber lightweight aggregate concrete (BFLAC) under high-temperature exposure, C40 lightweight aggregate concrete specimens with varying basalt fiber (BF) contents (0–0.4%) were designed. These specimens were subjected to elevated temperatures of 20, 200, 400, 600, 800, and 1000 °C, after which their residual compressive strength and residual splitting tensile strength were tested. The results indicate that the mechanical properties of all concrete groups deteriorated significantly with increasing temperature, with aggravated degradation observed above 400 °C. The incorporation of BF effectively enhanced both the compressive and tensile strengths of the concrete, with a more pronounced improvement in tensile strength; the optimal BF content was found to be between 0.2% and 0.3%. However, when the temperature exceeded 600 °C, the internal structure of the material suffered severe damage, leading to a significant reduction in the fiber reinforcement effect.