基于GSI原理瓦斯抽采钻孔收缩比评估方法及其应用

发布时间：2018-04-25 20:53

本文选题：GSI原理 + Hoek-Brown准则　；参考：《中国安全生产科学技术》2015年02期

【摘要】：瓦斯抽采钻孔收缩是致使排渣阻力增大、钻孔发生堵塞的主要因素。基于地质强度指标(GSI)法,分析了评估煤体力学参数的方法,探讨了Mohr-Coulomb与Hoek-Brown准则内在关系,从而能够应用较为广泛的方法验证和求解不同煤层条件下钻孔的变形量;提出了钻孔收缩比概念和计算方法,应用GSI原理对不同强度煤的钻孔收缩比进行定性分析。分析结果表明,钻孔收缩比受煤体强度变化的影响非常敏感,对于强度较低的煤体,钻孔变形量大,钻孔收缩严重,其结果缩小了钻孔的排渣空间,间接增大了钻屑运移、钻杆旋转及退钻阻力,使钻孔施工更加困难。结合工程案例,根据施工地点地质条件,科学评估钻孔收缩比并提出钻孔施工改进方案,通过工业性试验,钻进深度提高40%,钻进效率提高97.5%。
[Abstract]:The shrinkage of gas drainage borehole is the main factor that causes the slag drainage resistance to increase and the borehole clogging. Based on the geological strength index (GSI) method, the method of evaluating the mechanical parameters of coal body is analyzed, and the inherent relationship between Mohr-Coulomb and Hoek-Brown criterion is discussed, which can be widely used to verify and solve the deformation of boreholes under different coal seam conditions. The concept and calculation method of borehole shrinkage ratio are put forward, and the GSI principle is applied to qualitatively analyze the borehole shrinkage ratio of coal with different strength. The results show that the borehole shrinkage is more sensitive than that affected by the change of coal strength. For the coal body with low strength, the borehole deformation is large and the borehole shrinkage is serious. Drilling pipe rotation and back drilling resistance make drilling more difficult. Combined with engineering cases, according to the geological conditions of the construction site, the paper scientifically evaluates the borehole shrinkage ratio and puts forward the improvement scheme of drilling construction. Through the industrial test, the drilling depth is increased by 40 and the drilling efficiency is increased by 97.5.
【作者单位】：河南理工大学能源科学与工程学院;
【基金】：国家科技支撑计划项目(2013BAA03B02) 河南理工大学博士基金项目(B2014-053)
【分类号】：TD712.6

【参考文献】