大断面突出危险掘进工作面应力分布规律研究

Study on stress distribution law of large section outburst dangerous driving face

为分析大断面突出危险掘进工作面在采掘过程中的应力分布规律,采用现场实测的方法进行研究。可以看出,试验工作面煤体应力峰值区位于前方6~8 m,巷道帮外6 m煤体应力受掘进活动影响较小;掘进面后方下帮煤体应力随时间延长呈现降低趋势;巷道上帮煤体应力变化梯度比下帮快,且出现应力涨跌现象,上帮煤体更容易出现失稳破坏。可以对采掘工作面前方10~20 m应力分布状态进行实时监测,通过研究其与突出的耦合关系,提高突出的实时监测能力。特别对于地应力为主导的突出危险性,将提供新的综合防突技术指导,最终提供一种新的预测预报手段;应力传感器直径在50 mm左右,采用直径42 mm钻头施工监测钻孔,通过特殊操纵杆安装可很快固定传感器,并达到监测应力的目的。

In order to analyze the stress distribution law of large section outburst dangerous mining face,the field measurement method was used to study.Through the research,it could be seen that the peak stress area of the coal body in the test face was 6~8 m ahead,and the stress of the coal body outside the roadway was less affected by the mining activity;the stress of the coal body in the lower side of the roadway showed a decreasing trend with the extension of time;the stress gradient of the coal body in the upper side of the roadway was faster than that in the lower side,and the phenomenon of stress rise and fall occurred,and the coal body in the upper side was more prone to instability and failure.Real-time monitoring of stress distribution in the range of at least 10~20 m in front of the mining face could be carried out.By studying the coupling relationship between stress distribution and outburst,the ability of real-time monitoring of outburst could be improved.Especially for in-situ stress-dominated outburst danger,it would provide a new comprehensive technical guidance,and finally provide a new means of prediction and prediction.Stress sensor diameter was about 50 mm,using a diameter of 42 mm drill bit to construct monitoring boreholes,through the installation of special control rod,the sensor could be quickly fixed,and the purpose of monitoring stress could be achieved,so the installation was simple.