论文部分内容阅读
为了研究不同气体压力对软煤钻孔周围煤体应力及变形的影响,通过采集煤样、压煤成型、布设压电膜、钻孔实施及窥探等实验步骤,分析不同充气压力条件下钻孔周围应力变化及钻孔内部破坏变形情况及规律,得出随着充气压力的增大,钻孔周围应力集中逐渐向外围迁移,卸压带范围逐渐扩大;其中,在未充入气体时,实验钻孔周围卸压带约22 mm,在0.9 MPa气体压力作用下,其卸压范围增大到约60 mm;随着充气压力的增加钻孔内壁的破坏变形逐渐加剧。
In order to study the effect of different gas pressures on the stress and deformation of coal around the soft coal borehole, the experimental procedures such as coal sample collection, coal formation, piezoelectric film laying, drilling practice and snooping were used to analyze the influence of different gas pressure conditions on drilling The surrounding stress changes and the damage and deformation of the borehole. The results show that with the increase of the inflation pressure, the stress concentration around the borehole gradually migrates to the periphery, and the range of the pressure relief belt gradually expands. When the gas is not filled, the experiment The pressure relief band around the borehole is about 22 mm. Under 0.9 MPa gas pressure, the pressure relief range is increased to about 60 mm. With the increase of inflation pressure, the damage and deformation of the inner wall of the borehole is gradually aggravated.