Abstract:

To enhance safe and efficient cut-and-fill mining technology for inclined thin ore bodies, optimization research was conducted on the cut-and-fill mining method, with the Suichang Gold Mine in Zhejiang Province as the engineering subject. By establishing an ″inclination-thickness″ classification matrix (type Ⅰ inclined thin ore body: 30° < θ ≤ 55°, h ≤ 4 m; type Ⅱ inclined medium-thick ore body: 30° < θ ≤ 55°, h > 4 m; type Ⅲ steeply inclined thin ore body: θ > 55°, h ≤ 4 m. θ represents the inclination of the ore body, and h denotes the average horizontal thickness) based on geometric parameters, an integrated technical system combining mechanized upward horizontal layered cut-and-fill method with drift filling method was developed. A three-stage progressive methodology, involving geological modeling, numerical simulation, and industrial trials, was adopted to address key technical issues such as quantitative classification criteria, coordinated optimization of mining-filling parameters, and cemented filling processes of unclassified tailings. The results demonstrate that the application of trackless equipment increases stope production capacity to 250-300 t/d. The filling system of unclassified tailings, with a cement-to-tailings ratio ranging from 1∶4 to 1∶8, achieves a roof contact rate exceeding 90% through stepped baffle technology. Furthermore, the comprehensive ore recovery rate is raised to 95%, while the dilution rate is reduced to 8.5%.

Key words: inclined thin ore body, filling mining method, mechanized upward horizontal layered cut-and-fill method, unclassified tailing, cemented filling