A study of the dynamic movement rule of overlying strata combinations using a short‐wall continuous mining and full‐caving method

Abstract

At present in China, short-wall working face coal-mining methods are among the main methods used for the high-efficiency recoveries of boundary coal pillars and residual pillars. In traditional short-wall mining methods, overlying roofs are supported by coal pillars. However, issues such as the excessive number of coal pillars, low coal recovery efficiency, large areas of hanging roof arches, etc, have been encountered. In view of the aforementioned issues of the current short-wall mining technology, this study took the short-wall mining of the Yujialiang Mine in the Shendong mining area as the project background. The study then proposed a judgment method for the key stratum on the working face of the mine using a short-wall continuous mining and full-caving method. The proposed method was based on the theory of elastic plates and was verified using the theoretical analysis results of similar material simulation experiments. FLAC 3D software was adopted to analyze the stress and displacement evolution processes of the overlying rock strata during the advancement of the working face using a short-wall continuous mining and full-caving method. The results showed that the short-wall continuous mining and full-caving method not only had the ability to improve the recovery rate, but was also able to realize the effective control of the roof areas, thereby avoiding any large areas of hanging arches. The short-wall continuous mining and full-caving method is potentially of important significance for the improvement of coal recovery rates, as well as for the safe and highly efficient mining of boundary coal pillars and residual pillars in mines under special conditions. K E Y W O R D Scaving span, composite key stratum, numerical simulation, short-wall continuous mining and full caving, similar material simulation experiment | 2985 WEN Et al.

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