Analysis of the Impact of Shot-Blasting Treatment on the Tunnel Asphalt Pavement Texture Based on Geometric Parameters and Its Process Optimization

To enhance the skid resistance of tunnel asphalt pavements, this study investigates the regulation mechanism of shot-blasting treatment on pavement texture parameters. Utilizing three-dimensional (3D) laser-scanning technology, we acquired texture data from a highway tunnel in Guangdong Province, China, and established a multidimensional geometric parameter system encompassing amplitude, shape, and spacing characteristics. Through statistical analyses including paired sample t -tests and multivariate analysis of variance (MANOVA), we quantified the global impacts of shot blasting on texture parameters and evaluated the influence of equipment speed and lane type on treatment effectiveness. The results demonstrate that (1) shot blasting significantly improves amplitude parameters while reducing spacing parameters; (2) the passing lane exhibits superior amplitude improvement compared with the main lane due to its initial deeper texture; and (3) low-speed processing effectively stabilizes spacing parameter reduction, whereas high-speed operations, despite enhancing amplitude parameters significantly, tend to induce abnormal fluctuations in spacing parameters. These findings provide theoretical support for optimizing shot-blasting processes in tunnel asphalt pavement maintenance strategies.