Geostress measurement and evaluation of rock burst tendency in high altitude mining area

Covering hole stress release method and hollow postures triaxial strain gauge is used to measure the four levels of geostress in Jiama mining area, and eight groups of three-dimensional geostress state data are obtained, the geostress field distribution law are revealed, and the mining area geostress field model is established.According to the measured data of geostress and the test results of physical and mechanical properties of ore and rock, the rock burst tendency of surrounding rock is evaluated from multiple angles and levels by using the brittleness coefficient criteria, energy index criteria, TAO Zhenyu criteria and Erlangshan highway criteria.The results show that Jiama mining area geostress is dominated by horizontal tectonic stress, and belongs to tectonic stress mining area, the geostress level is medium.The maximum horizontal principal stress is about 2 times of the gravity stress, and its trend is N35.6W-N76.28W, and the minimum horizontal principal stress trend is N35.6W-N76.28W, the basic characteristics of geostress field is σ_h.max> σ_v≈γH> σ_h.min.The rock burst tendency of Jiama mining area is between weak to moderate, when the mining elevation is above 4 450 m, the surrounding rock has weak rock burst tendency, when the mining elevation is below 4 250 m, as the geostress increases, the surrounding rock has medium rock burst tendency.The results have important reference to guide the mine engineering design, stope layout, supporting parameters optimization and the ground pressure disaster prevention and control.