Fatigue Life Analysis of Basalt Fiber–Reinforced Concrete under Axial Constant-Amplitude Cyclic Tension

Abstract

The aim is to research the fatigue life of basalt fiber–reinforced concrete (BFRC) under axial constant-amplitude cyclic tension. The two factors, stress level and basalt fiber volume fraction, were considered. Twelve sets of concrete specimens were designed and fabricated to carry out axial tensile fatigue test studies by means of a self-developed concrete axial tensile test device. The whole process of BFRC axial tensile fatigue was analyzed and the effects of fiber content and stress level on the tensile fatigue life of concrete specimens were investigated. The research results show that the tensile fatigue deformation of BFRC can be divided into three stages: rapid growth stage, stable development stage, and fatigue damage stage. Compared with normal concrete, basalt fibers enhance toughness and resistance to cracking, the ultimate fatigue strain of BFRC is relatively large, and the tensile fatigue damage shows certain plastic damage characteristics. The addition of basalt fibers improves the tensile fatigue strength of concrete by about 5%–8%. With the increase of the volume fraction of basalt fiber, the fatigue life of BFRC showed the change rule of increasing first and then decreasing. When the volume fraction of basalt fibers was 0.3%, the fatigue life increased the most. The probability distribution of the BFRC fatigue life conforms to the two-parameter Weibull distribution, and its correlation coefficient is greater than 0.92. Based on the fatigue test data, the tensile fatigue equation containing fiber characteristic parameters under different failure probabilities was established, which can effectively predict the fatigue life of BFRC. The research results can provide a reference for the fatigue-resistant design of BFRC structures. The findings of this research have important practical implications for the design of concrete structures, especially in earthquake-prone areas. BFRC has excellent mechanical properties, including higher tensile strength and better fatigue resistance. These properties enhance the structural integrity of concrete under cyclic loading conditions, which is critical in earthquake-prone regions. The fatigue life prediction equations proposed in this study for BFRC are a reliable analytical tool that enables engineers to accurately assess the long-term performance of BFRC structures under different cyclic loading scenarios. This assessment is critical to predicting the long-term performance of a structure and ensuring that the structure can withstand the rigors of long-term cyclic loading without compromising safety or integrity. Accurately predicting the fatigue life of a structure can help develop more durable structures. Through these predictions, engineers can optimize designs to improve the service life and reliability of concrete structures, thereby reducing maintenance costs and minimizing the risk of structural failure. This study provides an important reference for advancing the practical application of BFRC in civil engineering and deepens our understanding of the performance characteristics of BFRC.