1. State Key Laboratory for Geomechanics & Deep Underground Engineering,China University of Mining & Technology,Xuzhou　 221116,China;2. School of Mechanics and Civil Engineering,China University of Mining & Technology,Xuzhou　 221116,China

采用锚杆轴力无损检测技术,对采动影响区域锚杆轴力随工作面推进变化情况进行了大量现场测试,发现锚杆轴力变化与采场超前支承压力分布具有明显的对应关系。以淮南某矿回采工作面运输平巷锚杆轴力实测数据为例,检测结果表明:在距采煤工作面0~20 m范围内,受采动影响严重,锚杆轴力变化较大;在距工作面5 m范围之内,存在支承压力减压区,此区域内锚杆轴力降低;在距工作面5~20 m范围内,对应着支承压力增压区,此区域内锚杆轴力增加,且锚杆轴力峰值位于距工作面煤壁10 m左右;在20 m以外区域,受采动影响较小,对应着支承压力稳压区,此区域内锚杆轴力变化不大。在基本顶断裂后,位于减压区内的顶板锚杆轴力急剧下降,同时,位于增压区内的锚杆轴力峰值明显下降且位置向前发生跳跃前进。研究结果表明,采动支承压力分布与锚杆轴力变化存在良好的对应关系,基本顶断裂可在锚杆轴力动态响应上得到有效体现。

Using non-destructive testing technique for axial bolt load,large amounts of field measurements have been performed on the variation of the axial bolt load with mining advance in mining disturbancezones of a working face. It was found that an obvious correspondence between the variation of axial bolt load and the abutment pressure distribu- tion in front of theface exist. Given a mine in Shanxi Province as an example,the measured data of axial bolt load in the belt entry of the face show that axial bolt load varies considerably in the zone from 0 to 20 m before the working face owing to heave mining disturbance. Within the zone of 5 m before the face,a releasing area of the abutment pres- sure exists and the axial bolt load drops. The abutment pressure is concentrated in the zone from about 5 m to 20 m in front of the faceand theaxial bolt load increases correspondingly;moreover,the bolts’ peak-load is located at about 10 m from the face. In the zone of about 20 m far away from the face,the abutment pressure keeps stably and theaxial bolt load is not likely to change quickly. After the failure of main roof,the axial load of roof bolts decreases considera- bly in the releasing area of the abutment pressure,meanwhile the peak value of the axial bolt load declines violently and its location leaps forwards. The research results demonstrate that the variation of the axial bolt load and the abutment pressure distribution are in good correspondence,meanwhile the failure of main roof can be effectively reflected on the dynamic response of theaxial bolt load.

国家重点基础研究发展计划(973)资助项目(2013CB227900)；国家自然科学基金资助项目(51227003,51404262)；

Chen Yanlong,Zhang Houquan,Wu Yu,et al. Field measurement study of the relation between mining pressure and axial boltload[ J]. Journal of China Coal Society,2016,41(5):1106-1110.