Effects of Silane-Coupling Agent Pretreatment on Basalt Fibers: Analyzing the Impact on Interfacial Properties and Road Performance

Given the application characteristics and shortcomings of basalt fiber in road engineering, improvements to its reinforcing effect in asphalt mixture, such as reinforcing, toughening, and bridging, are needed. A silane-coupling agent (ammonia propyl triethoxysilane, or KH550) is used to pretreat and modify the surface of basalt fiber. A comprehensive series of tests, including heat resistance, basalt fiber absorption asphalt capacity, segregation and dispersion performance, and micromorphology of a drawing fracture surface, is conducted to examine the road performance of the modified basalt fiber. Furthermore, the modification mechanism of the KH550 solution on the basalt fiber interface is analyzed using infrared spectrometry, scanning electron microscopy, and X-ray energy spectroscopy. The results show that the KH550 solution can significantly improve the interfacial properties of the basalt fiber, form convexities with stable chemical bonds on the basalt fiber surface, and significantly enhance its cohesive force with asphalt. Overall, the KH550 solution significantly enhances the effect of the basalt fibers in an asphalt mixture.