Is mine engineering geological disaster the main internal cause of mine safety accidents?

Mine engineering geological disasters are the main internal causes of mine safety accidents.

Mine engineering geological disasters mainly refer to the redistribution of mine geostress caused by mining, which leads to disastrous situations such as rock movement and rock mass destruction. These hidden dangers can be eliminated by mine rock mechanics engineering design and mine safety monitoring and prevention technology. However, the geological conditions of metal mines are harsh, the hidden dangers of ground pressure disasters are great, and the influencing factors are complex. The geological structure of the deposit, the environmental conditions of in-situ stress, the weak zone of rock stratum, the cracks in rock mass, groundwater, geothermal energy and the influence of excavation all restrict the stability of mining engineering and surrounding rock.

Types of engineering geological disasters in mines

In addition to engineering disasters such as landslides that may occur on surface slopes and tailings dams, the types of geological disasters caused by ground pressure in metallic and nonmetallic mines also include:

(1) Surface subsidence. Due to the influence of shallow mined-out areas or large-scale mining, rock movement near the surface may cause certain harm to buildings and roads on the surface, and some even cause landslides. Surface subsidence in metal mines is widespread and extremely harmful. When blasting or rock strata move to a certain extent, large-scale collapse will occur in goaf. Due to the sudden collapse of mined-out areas, huge disasters such as seismic waves and air shock waves will occur.

(2) Roof caving. Roof fall accident is one of the most common disasters in underground mines, and it also has the highest accident rate. Roof fall includes falling rocks, falling blocks, bad stratum collapse, and various collapses caused by mining and geological structures. In particular, the difficult-to-mine bodies and weak interlayers with poor ore-rock stability are prone to large-scale caving, resulting in roof caving accidents in stopes and roadways.

(3) Deep rockburst. In recent years, some metal mines have entered the deep mining below 1000 m, and rockburst often occurs in hard rock strata under high pressure. Dongguashan copper mine has been developed to 1 100m, and there are rock bursts and rock ejections in the deep part; The mining depth of Hongtoushan Copper Mine is about 1.337m, and the mining depth is about1.654,38+000 m. The granite pillar and footwall in the large mining area have been subjected to large rock bursts many times, and the surface noise is thunderous, which seriously damages the shaft and roadway engineering and causes harm to production. Dachang 105# orebody buried depth 1000m, due to the excavation of civilian mining, a tall goaf was formed. In March and April of 200 1 year, there were many huge rockbursts and microseisms, which shook the surface and caused large landslides in deep civil mining sections.

(4) Groundwater seepage and sudden water inrush. Although sudden water inrush is not directly caused by ground pressure, it is closely related to mining operations. Once close to the roadway and goaf with water, or encounter caves and underground rivers, it will suddenly become unstable in isolated strata, which is easy to cause disasters.

(5) Disasters and accidents caused by abnormal production. Many people command illegally, do not act according to objective conditions, indiscriminately mine and dig, do not deal with mined-out areas, disrupt mining order, destroy isolated safety pillars, and cause disasters and accidents. For example, 1998, after the horizontal isolated coal pillar in the fire area of Tongkeng Mine was destroyed by civilian mining, it caused a large-scale collapse accident in the civilian mining face and broke through the surface, and the fire area was rekindled, resulting in resource loss and great harm.