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Short wall mining technology is an important method to coal resource mining in the United States, Australia and other countries, and also one of important methods to boundary coal resource recovery in China. Short wall mining technology through leaving a large number of coal pillars to support and control roof, induces a series of accidents, such as large area roof suspended, collapse and shock, which restricts the further popularization and application of short wall mining technology seriously. By improving the existing short wall mining technology, the article proposed short wall continuous mining technology with full roof falling, and designed measures to control roof. The main research work is as follows: (1) By reducing and eliminating coal pillars in mining section as much as possible, including entry protecting pillar and pillar between caverns, also ensured stability of roof during mining period at the same time; after mining, roof can be collapse, to prevent large area roof suspended and collapsed inducing shock accidents; mining process and equipment of short wall continuous mining technology with full roof falling, were designed comprehensively. (2) Measures to control roof of short wall continuous mining technology with full roof falling are designed, using self-moving hydraulic support to control roof of mining cavern, anchor bolt and cable to ensure branch and cross entries stable during mining period, and forced caving technology to control large area roof suspended; (3) Short wall continuous mining technology with full roof falling and roof control measures were successfully industrialized in 42,210 boundary coal face of Yujialiang coal mine, which belong to Shenhua energy group in Inner Mongolia. The research result is significant to enrich and develop short wall mining technology.

For the thick alluvium and thin bedrock coal seam mining in East China, it is easy to produce water by pressing the frame. Taking the engineering geological conditions of the thin bedrock coal seam 1611 (3) working face in the Zhangji Coal Mine of Huainan Mining Group as the research background, the breaking law of the thin bedrock coal seam working face with thick alluvium was studied by using a similar material physical simulation experiment and theoretical analysis. It is revealed that under the load transfer of the loose aquifer, the roof fracture of the stope with thick alluvium and thin bedrock is characterized by large and small periodic ground pressure, and the combination failure of the high key stratum and the low key stratum with large cycles is prone to support crushing accidents. Based on this, the safety mining technical measures of reducing the fracture distance of the high key stratum by forced roof caving are proposed, and the reasonable blasting parameters are calculated. After field application, no support crushing accident on the working face was recorded, and the mining was safe, which provides a technical reference for the mining of the working face under similar conditions.

Accurate and efficient acquisition of information about the dynamic characteristics of coalface overburden can provide an important theoretical basis for green mining in coal producing regions in western China. In this study, a novel method for comprehensively detecting the dynamic behavior of coalface overburden is proposed in order to address deficiencies of the existing detection methods. The new method combines surface radon measurement, overburden borehole imaging, and underground pressure observation into a comprehensive detection technology system, resulting in spatial and temporal integration of surface, overburden, and underground detection. To examine the feasibility of the proposed method, a field experiment was carried out at #1103 coalface in the Suancigou Coal Mine, which is operated by the Inner Mongolia Yitai Coal Co. Ltd. The results of the three approaches are largely consistent and they complement one another. But it must be pointed out that this method needs to be further improved by more field experiments. Based on the experimental results, a technique for forced caving by presplit blasting of the overburden was developed and then implemented to #1103 coalface. The practical use of the technique led to good results: it effectively prevented roof-associated accidents by controlling the first weighting step to about 82 m, contributing to safe and efficient mining; coal production was expected to increase about 126 kilotons.