Research progress on mechanism and technology of “disaster treatment by blasting” in deep coal mine

As a typical feature of “three high and one disturbance”, the superposition of high in-situ stress and mining stress is one of the main causes for frequent geological disasters in deep mines. It is easy to cause strong rock pressure, rock burst and large deformation of mining roadway, which is a major hidden danger for safe and efficient mining in deep mines. In order to solve the problems of disaster control such as strong mine pressure, pressure bumps and large deformation of mining roadway in deep mine, the mechanism and new prevention and control method of “disaster treatment by blasting” in deep mine are put forward based on blasting technology, so as to realize the goal of “untie connection, weaken peak, control deformation” in underground mine disaster control. Firstly, the in-situ monitoring method of “point-line-surface-body” explosive fracture field is proposed, the formation mechanism of explosive fracture network in coal mine blasting site is revealed, and the stress control mechanism of surrounding rock in blasting pressure relief is clarified, which provides a theoretical basis for the field application of blasting technology in pressure relief and anti-scour engineering. Secondly, the key technologies of blasting pressure relief in deep mine are pointed out from three aspects: parameter design, advanced equipment and effect evaluation, covering the whole process of blasting pressure relief including parameter design, drilling and punching, charge plugging and comprehensive evaluation. Then, taking Huainan mining area (Zhangji coal mine), Luxi mining area (Xinjulong coal mine) and Ningdong mining area (Meihuajing coal mine) as typical engineering cases, the on-site targeted research of “disaster treatment by blasting” guiding blasting pressure relief was carried out, and the loose pre-splitting control blasting, high-level roadway fine control blasting and mining roadway blasting pressure relief stress control technology were formed respectively. Finally, based on the intelligent design of blasting parameters, the unmanned control of construction equipment and the intensive charging of ultra-long blastholes, the development trend of “disaster treatment by blasting” is prospected. Based on the perspective of intelligence, digitization and informatization, the possible research priorities and challenging problems of blasting pressure relief engineering in the future are put forward, which has important theoretical and practical significance for disaster management in the process of deep coal resource mining.