钻孔摄像测试围岩松动圈的机理与实践

利用全景钻孔数字摄像技术和数字图像处理与分析方法,研制了全景数字钻孔摄像煤矿巷道围岩松动圈测试系统,该系统由硬件和软件2大部分组成,硬件系统包括高压密封摄像定位磁性罗盘以及微型CCD摄像机等,软件系统则包括钻孔图像实时监视与实时处理(如图像无缝拼接、平面图展开、三维钻孔岩芯生成)以及松动圈的分析程序.在松动圈识别关键技术中,提出了用钻孔图像中围岩裂缝的圆形度指标作为判断围岩松动圈标准的新思路.首次将其应用于山东七五煤矿深井围岩松动圈的测试工作,获得了围岩松动圈厚度值在巷道断面不同部位有较大差异的分布规律,并和传统的围岩松动圈超声波测量法比较,误差在3.5%之内,验证了钻孔摄像技术测量松动圈的可靠性,为高应力地下工程围岩松动圈厚度值的测试提供了新的方法.

Borehole Camera Technology for Measuring the Relaxation Zone of Surrounding Rock. Mechanism and Application

A panoramic borehole camera technology (BCT) and digital image processing method was developed by constructing a system composed of hardware and software. The technology was used for measuring the relaxation zone of surrounding rock with the borehole camera. The hardware consists of a mini CCD camera and a high-pressure sealed magnetic compass that is used for camera positioning. The software includes real-time image monitoring and a processing program that includes the procedure for analysis of the relaxation zone. The roundness of cracks in the boreholes is taken as the index for identifying the relaxation zone. The system was used to measure the relaxation zone of a deep roadway in the Qiwu coal mine of Shandong province. The distribution of the relaxation zone around the roadway was obtained. The results show that the thickness of the broken rock zone varies with the measuring position within a cross section of the roadway. The reliability of the measuring method was tested and verified by comparing the data from BCT with those measured by an ultrasonic method: The difference is less than 3.5%. The system provides a new method for the measurement of the relaxation zone when engineering deep underground.