Pre-reinforcement grout in fractured rock masses and numerical simulation for optimizing shrinkage stoping configuration

• Published in: Journal of Central South University Vol. 24; no. 12; pp. 2924 - 2931
• Main Authors: Yu, Shao-feng, Wu, Ai-xiang, Wang, Yi-ming, Li, Tao
• Format: Journal Article
• Language: English
• Published: Changsha Central South University 01.12.2017; Springer Nature B.V
• Subjects: CAD; Cement reinforcements; Computer aided design; Computer simulation; Configurations; Drilling; Engineering; Grout; Mathematical models; Mechanical properties; Metallic Materials; Mining; Mining industry; Occupational safety; Optimization; Pillars; Porosity; Recovery; Shrinkage; Stoping; Underground mines; cement-sodium silicate grout; stoping configuration; three-dimensional numerical simulation; effect of pressured grout; shrinkage stoping mining
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-017-3706-3

Proper room and pillar sizes are both critical factors for safe mining and high ore recovery rate in shrinkage stoping mining of underground metal mines. The rock masses of Tangdan copper mine of China are fractured, which needs much reinforcement and support prior to mining. Cement-sodium silicate grout technology was selected, then its related parameters such as grout pressure, diffusion radius and time were calculated and proposed. In order to test the effect of the pressured grout in the fractured No.4 ore block, field experiments were conducted. To optimize stoping configuration, three-dimensional numerical simulation with ANSYS and FLAC 3D softwares was proposed. The results show that the drilling porosity and mechanical properties of the rock masses are increased obviously. After grout, ore recovery rate is increased by 10.2 % employing the newly designed stoping configuration compared with the previous. Last, analyzed from the surface movements, roof subsidence and the maximum principal stress of the pillars, the mining safety is probable of being ensured.