断层破碎带岩性复杂,巷道压力显现规律多变。对巷道过断层破碎带的监控量测能够及时掌握断层破碎带围岩的变形与支护结构受力信息,评价各种支护所取得的效果及判断施工方案的合理性。淮南矿区顾北煤矿南翼回风大巷穿越断层破碎带,区域地质条件复杂,受构造运动影响,围岩内赋存高水平地应力,巷道处于深部大规模松软围岩内。为研究施工期和运行期巷道围岩的稳定性演化规律,对围岩表面位移、深部位移、锚杆和锚索锚固力及支架压力的变化和分布规律进行监控量测。监测结果显示:(1)由于受F92大断层的水平剪切和挤压作用,与顶拱和两肩相比,巷道两帮的水平位移较大,而锚杆受力较小,锚固作用得不到有效发挥,因此,在F92大断层附近增大了锚索和注浆的支护强度;(2)围岩表面位移和深部位移的监测结果均呈现"底臌变形大于两帮收敛大于拱顶下沉"的分布规律,显示出底板是巷道支护的薄弱环节,因而提出应用底角注浆锚管和帮脚锚杆抵抗底角应力集中区的剪切滑移,底板锚索和底板注浆增强加固底板,提高底板岩体抗剪强度的支护修改方案,底臌量得到有效控制;(3)U型钢支架压力的监测结果显示,围岩作用于U型钢支架上的压力仅为0~0.24MPa,远小于0.4MPa的支架设计承载能力,说明巷道稳定主要是依靠锚注支护来维护,而U型钢支架的作用主要是巷道施工过程中工作面的安全防护。通过对监测结果的分析,为巷道的信息化施工和设计方案的优化调整提供依据。其监测分析成果也可为类似复杂条件下巷道的开挖支护设计和施工提供参考。
The lithology in fault fracture zones is complex and the pressure in roadway in these zones is variable.The deformation of surrounding rock and pressure on support structure in fault fracture zone can be grasped through the monitoring measurement of roadway.Based on the measurement,the effects of various supports and the rationality of construction scheme are evaluated.Ventilation roadway in south of Gubei coal mine in Huainan mine area passes through the fault fracture zone.In this area,the geological condition is complex.Because of the influence by tectonic movement,the geostress of surrounding rock is high and the surrounding rock of roadway is large-scale loosened rock.In order to analyze the stability and study the deformation law of surrounding rock in the periods of construction and operation,the surface displacement of surrounding rock,deep displacement,stress of anchors and cables,support pressure and the variation distribution regularity of loosened zone of surrounding rock are studied through the field measurement.The results show that:(1) The horizontal displacement of wall of roadway is larger than that of roof and spandrel;and the stress of anchor is small because of the horizontal shear force and squeeze force from fault F92.And it means that the action of anchoring is not effective.Hence,the strength of anchors and the grouting near fault F92 was reinforced.(2) From the measurement results of surface and deep displacement of surrounding rock,the floor dilates,the two walls converge and the roof sinks.It means that the floor is the weak part in the support of roadway.A revised support scheme is proposed:grouting tube at the corner of floor and rockbolts at wall corner are used to resist the shear displacement at the floor corner with concentrated stress;and the floor is reinforced by anchor and grouting to improve the shear strength of rock mass near floor.The dilation of floor is controlled effectively which means the support effect is good.(3) From the measurement result of pressu