松软煤层抗张强度及防隔水煤柱宽度的研究

Application of Point Load Test in Research on Tensile Strength of Loose Coal Seam and Width of Coal Pillar

在矿井生产过程中,为防止发生突水事故,常在井下设置防隔水煤柱。通过留设矿井防隔水煤柱,对矿井延长服务年限和煤矿水害防治具有十分重要的意义,而研究合理的防隔水煤柱宽度,能够更加安全、合理、高效地开采煤炭资源。通过点荷载试验测定了祁南煤矿34下6工作面采取的松软结构煤体的点荷载强度指数。考虑到尺寸效应,对不规则试件的结果进行修正后,利用点荷载强度间接获取松软煤层抗张强度。在矿井特定位置留设防水煤柱时,煤层的厚度和水头压力是固定的,煤柱的留设宽度仅为煤层的抗张强度的函数。因此,根据经验公式可计算出防隔水煤柱的合理留设宽度。

In the mine production process,to prevent water inrush accidents,water-proof coal pillars are often installed underground.It is of great significance for the mine to extend the service life of the mine and the prevention and control of coal mine water hazards by leaving the mine to prevent water-proof coal pillars.The study of reasonable water-proof coal pillar width is more safe,reasonable and efficient for mining coal resources.The point load strength index of the soft structure coal body adopted in the lower 6 working face of Qinan Coal Mine 34 was measured by point load test.Taking into account the size effect,after correcting the results of irregular specimens,the point load strength is used to indirectly obtain the tensile strength of the soft coal seam.When leaving a waterproof coal pillar at a specific location in a mine,the thickness and head pressure of the coal seam are fixed,and the width of the coal pillar is only a function of the coal seam's tensile strength.Therefore,according to the empirical formula,the reasonable leaving width of the anti-water coal pillar can be calculated.