Multi-level induced healing of steel bridge deck asphalt pavement: an energy-saving and emission-reducing microwave heating method

This study proposes a novel, eco-friendly microwave-induced SBDAP healing method to overcome the high resource consumption and pollution of traditional maintenance. Key parameters, including heating duration (t), power (P), damage degree (d), and waveguide height (h), were ranked by healing rate impact across layers. Optimal conditions were derived from trend analysis of these factors, followed by the design of a three-phase adjustment strategy. Environmental benefits were quantitatively evaluated. The results showed that P had the greatest effect on the healing rate of SBDAP, followed by t, then d, and finally h. It is recommended that microwave-induced healing maintenance should be carried out promptly at the early stage of damage, with optimal working conditions of 90 s and 800 W. The optimal waveguide heights for the top, middle, and lower layers of SBDAP were 60 mm, 20 mm, and 24 mm, respectively. The three-stage regulation strategy enables dynamic adjustment of waveguide height within 90s according to layer-specific damage, allowing the healing rates of the top, middle, and lower layers to reach 58.47%, 71.79%, and 84.53%. More importantly, this novel technology demonstrated significant environmental benefits, reducing energy consumption by 91.67% and carbon emissions by 90.72%.