431 / 2024-04-09 17:58:29

Identifying the size and load-bearing capacity of artificial protective pillars for the entry gate road during deep mining in thick coal seams in Quang Ninh coalfield

thick coal seam, artificial protection pillar, pillar width, compression resistance strength

3、深地工程与能源利用 > 1、深部岩土力学基础理论

Using artificial pillars to replace the coal pillars to protect the entry gate road is one of the most effective solutions to minimize coal losses and enhance safety in mining thick coal seams. Currently, in the Quang Ninh coal region (Vietnam), mining operations are conducted at a depth of -350m and preparing for mining down to -500m. To determine the width and load-bearing capacity of the artificial pillars, more detailed studies are needed for each specific geological condition. This paper utilizes Phase 2 numerical simulation software to analyze the relationship between strength and compression coefficient with the width of the artificial protective pillars for entry gate roads in thick coal seam mining in the Quang Ninh coal region. The study results show that the relationship between the width of the artificial pillars and the dip angle of the seam follows the law of a linear function, with the size of the protective pillars increasing with the depth of mining. At a mining depth of -500m, the pillar size varies from 1.4 to 2.4m. Increasing the compression resistance of the protective pillars reduces their width while increasing the dip angle of the seam also increases the required width of the pillars. The correlation coefficient (Pearson) between the dip angle of the seam and the width of the pillars is strongly correlated (Pearson = 0.621). The remaining relationship between the width of the pillars and the mining depth is directly proportional and weakly correlated (Pearson = 0.532), and between the width of the pillars and the compression strength of the pillars is inversely proportional, and weakly correlated (Pearson = -0.177). Therefore, when mining under corresponding conditions, it is necessary to select the appropriate size and compression resistance of the artificial pillars to ensure their load-bearing capacity.