Determination of temporary support for squeezing zone underground mine PT. Cibaliung Sumberdaya

[摘要] Underground Mining activity will always face deformation and instability of the rock mass around the underground openings. A large deformation was reported to occur on decline tunnel of PT. Cibaliung Sumberdaya (PT. CSD). Prior to this event, the same tunnel, which the tunnel wall had been refurbished into the proposed original shape. This implies that the squeezing zone had developed around the tunnel and the same support system couldn't resist the increasing load. Therefore, an analysis of squeezing zone around the excavation should be carried out. Conducted analysis started by the modelling the excavation should be carried out. Conducted analysis started by modelling the excavation the tunnel to get causing the cross cut failure. Then, back analysis was carried out to estimate the decreasing strength of the rock mass inside the squeezing. After that, squeezing zone can be determine the support systems to prevent the failure of rocks. The strain from back analysis results showing that similarity compared to the monitoring result when the modulus deformation E and the strength parameter mb and s of Hoek-Brown Failure criteria of the materials in the squeezing zone is 40 % peak strength. Analysis for temporary support shows that need 250 mm thick shotcrete, 1 m of spacing rock bolting, and 0.5 spacing reinforcement beam. Although, the floor of tunnel should be given extra consideration because could given high load, so must be installing rock bolt to helping stabilization.

[发布机构] Mining Engineering, Faculty of Mineral Technology, UPN Veteran Yogyakarta, Jl. SWK 104, Condongcatur, Daerah Istimewa Yogyakarta; 55283, Indonesia^1

[效力级别] 矿业工程

[关键词] Face deformations;Hoek-Brown failure;Monitoring results;Strength parameters;Temporary support;Underground mine;Underground mining activities;Underground opening