“顶板-煤层”结构体多场应力控制防冲技术原理及优化设计

Rock- burst Prevention Technology Theory and Optimization Design With Multi- field Stress Control on "Roof- seam" Structure Body

以典型的深部强冲击危险矿井为背景，通过对“顸板-煤层”结构体受力状态的分析，建立从区域应力协调到局部应力控制的以“顶板-煤层”结构体稳定性为基础，以应力控制为中心的多场应力控制防冲技术体系，通过数值模拟和理论分析对现场的区段煤柱留设宽度、巷道断面尺寸及布置方法、煤层卸压爆破及大钻孔卸压等区域应力协调和局部应力控制技术手段的相关参数进行优化设计。研究发现，对于强冲击危险工作面，区段煤柱留设宽度在3～4rn时对冲击地压防治有力；大断面沿顶巷道布置方式更有利于冲击地压的防治，但当断面尺寸增大到一定程度时其应力控制防冲效果趋于稳定。煤层卸压爆破应根据卸压位置的不同在爆孔深度、封孔长度等参数上进行动态调整，大钻孔卸压采用孔深30m，孔径130mm，孔间距1．2m参数时，应力控制防冲效果最为明显。

Taking a typical deep mine with high risk of rock - burst as background, the stress state of ＂roof - seam＂ structure body was analyzed, and a rock - burst prevention technology system is established based on stability of ＂roof- seam＂ structure body and taking stress control as the center. According to the numerical simulation and theoretical analysis, the relevant parameters which include width of section coal pillar, size and layout of roadway and some technology methods of regional stress coordination and local stress control such as coal blasting for pressure relief and big borehole for pressure relief were designed and optimized. The study shows that width of section coal pillar which is from 3 to 4 m has a good effect on prevention for rock - burst, the roadway layout with big size along roof can prevent the occurrence of rock - burst better. However, the effect of rock - burst prevention by stress control will not change with the increase of size of roadway. Some parameters including depth of blasting holes and length of sealing have to make a dynamic adjust- ment. When the depth of hole is 30 m, diameter of hole is 130 mm, space of hole is 1.2 m, the stress control is obvious.