构造复杂区域巷道控顶卸压原理与支护技术实践

PRESSURE-RELIEF PRINCIPLE IN ROOF CONTROL AND ITS APPLICATION TO ROADWAYS IN COMPLEX GEOLOGICAL STRUCTURE AREAS

针对构造复杂区域内煤巷存在的高应力、围岩破碎和支护困难等问题,提出了控顶卸压原理及配套的三锚支护技术,即在巷道掘进过程中,首先以较小的断面进行超前掘进,并对顶板采用高强度锚杆进行及时支护,而对巷道两帮煤体不支护,允许两帮煤体产生一定的变形和破坏,形成松动圈,从而使围岩中的高应力得到释放;当两帮煤体出现片帮后再进行刷帮和锚杆支护,并对顶角补充锚杆进行支护;然后再采用预应力锚索对顶板进行加强支护,且对巷道底角采用内注浆锚杆进行锚注加固。这样形成了一套完善的控顶卸压原理和三锚支护技术。该原理和技术得以应用于肥城矿区陶阳煤矿构造复杂区域煤巷的支护实践,经回采实践和矿压观测表明,取得了较好的技术与经济效果,为构造复杂区域煤巷的支护提供了一条有效途径。

This paper proposes the pressure relief principle of roof control and the corresponding ＂three bolting＂ support technique to solve the problem in supporting coal roadways with high ground pressure, cracked surrounding rock and support difficulty. The practical process of this technique involves two steps in. coal roadway excavation. The first step involves the lead-excavation in small section and the only bolting support in time to the roof plate stratum with high strength bolts, but no support to the side coal seam, which allow some deformation and fracture to the side coal seam, and the loosening circle is formed gradually, the high stress in surrounding rock is released. Then the enlargement is carried to the two sides of the coal roadway and the bolting support to the side coal seam and the top of the roof plate is added with high strength bolts in time after the enlargement when the side coal seam appears sloughing. In the second step, the prestressed cable is used as reinforced support to the roof plate, and the reinforcement by bolting and grouting with inside grouting bolt is applied to base angle. As a result, a suit of technique of the pressure relief principle to the roof control and the corresponding ＂three bolting＂ support technique is formed. These principle and technique have been applied to the coal roadway support in complex geological structure areas of Taoyang coal mine at Feicheng mining area. After the support practice and observation on rock pressure, satisfactory benefits both in technology and in economy are gained, which provides a new approach in support of the coal roadways under difficult conditions.