Seventy years innovation development and popularization practice of coal mineconstruction technology and equipment in China

The paper comprehensively summarizes the process of China's coal mine construction technology from introduction and absorption to independent development since the founding of New China more than 70 years ago, as well as the important achievements in basic research, process innovation, technological breakthrough, equipment development and achievement transformation, involving drilling and blasting method, freezing method, grouting method, drilling method, caisson method and other drilling technology as well as coal mine rock tunneling technology. At present, the mechanization and automation level of drilling and blasting equipment mainly for drilling and blasting rock has been significantly improved, and the comprehensive drilling technology for short-segment excavation of kilometer-level deep wells has been mature, and the maximum depth of vertical shaft drilling has reached 1341.6 m.The level of geological support technology for drilling and tunneling such as freezing method and grouting method has been significantly improved, gradually replacing the curtain method, sheet pile method and dewatering method and other drilling technology. The maximum frozen depth of vertical shaft is 990 m, and the maximum frozen section of inclined shaft is 681 m. The longest inclined shaft of 5875 m is built by working face grouting, and the ground pre-grouting reinforcement depth is 1355 m.Breakthroughs have been made in the technology of mechanical rock breaking and tunneling. The maximum drilling diameter of reverse drilling rig is 6 m, and the maximum drilling depth is 562 m.The maximum drilling diameter of vertical drilling rig is 10.8 m, and the maximum drilling depth is 660 m, and the application range is gradually expanded. The drilling method of vertical tunneling machine has achieved a breakthrough of zero, which has laid a foundation for intelligent drilling of coal mine vertical shaft. The operation line of the mechanized excavation method of the rock tunnel has been formed, and the average tunneling speed of the full section tunneling machine is more than 400 m/month. In summary, the innovation and development of coal in China mine construction technology and equipment in the past 70 years has significantly improved the operation environment, construction efficiency and safety level of the coal mine tunneling, realized the unmanned and fully mechanized operation of the tunneling working face, solved the problems of the tunnel construction in each stage of coal development in China, and ensured the basic construction and mining continuous construction of coal mines. At the same time, the technical equipment developed from the coal mine construction and the successful experience have been promoted and practiced in the underground engineering fields such as hydraulic power generation, municipal rail transit, mountain traffic tunnels, water diversion tunnels, and made contributions to the construction of national key projects and the development of national economy.