Abstract:
In order to solve the problems of depression and mudification on rainy days and dust on sunny days when using powdered blasting waste rock as the mining road surface layer in Zijinshan Au−Cu Mine, tests were conducted on self-repairing surface layer materials. After establishing evaluation criteria, the strength performance and water stability characteristics of self-repairing surface layer materials were analyzed using unconfined compressive strength, saturated compressive strength, and water stability index. The results show that adding a certain amount of quicklime to the surface layer of powdered blasting waste rock can effectively improve its water stability performance, but at the same time, its strength performance also decreases. Therefore, a 4 % quicklime dosage can be used for the surface layer to improve its water stability performance while maintaining a certain strength performance. As the PAM dosage increases from 0.025 % to 0.100 %, the initial unconfined compressive strength and saturated compressive strength of the sample show similar trends and meet the standards within a specific PAM dosage range. The water stability index first increases and then decreases, reaching its maximum at 0.075 % PAM. Therefore, in practical engineering, adding 4 % quicklime and 0.075 % PAM and setting a self-repairing surface layer with a mixing moisture content of 11 % can meet the strength and water stability performance standards of open-pit mine road surface layers, while reducing the occurrence of micro-cracks.