Detection method of roadway roof rock Platts coefficient while drilling based on sound level meter

Abstract

The invention discloses a method for detecting while drilling the Platts coefficient of roadway roof rock based on a sound level meter, aiming at the problem of detecting while drilling the Platts coefficient, which is an important rock mechanics index affecting the roof anchoring support scheme of coal mines, in the roadway. Drill holes of Φ32~42mm on the top plate. A bearing-type drilling-while-drilling device with a sound level meter probe is installed behind the drill bit. The method combined with the reading of the scale drill pipe is used to test the drilling volume of different depths during the drilling process. The decibel value, combined with the standard library of rock Platts coefficient of 0.3 to 20 established in the laboratory, by comparing the decibel value of the in-situ rock drilling volume in the roadway, the Platts coefficient of the rock within the drilling range of the roadway roof can be quickly obtained, and the drilling process can be calculated. Harmful noises are transformed into beneficial sound sources, enabling detection while drilling technology. It is suitable for the detection of Platts coefficient of typical sedimentary rocks such as sandstone, shale and mudstone in coal measure strata while drilling. It has the advantages of convenient on-site use, simple operation, low labor intensity and no influence on normal production.

Description

technical field [0001] The invention relates to a detection-while-drilling device and method, which belong to the technical field of mine roadway support, and are especially suitable for roadway roof rock based on a sound level meter under geological conditions where the distance between bedding planes between different lithology rock layers on the roof of a coal mine roadway is small. Platts coefficient detection device and method while drilling. Background technique [0002] Roadway support is a key technology for safe coal mining, and roof accidents account for a considerable proportion of mine disasters. The main reason for roof accidents is that the lithological characteristics of local roofs have not been detected in time, resulting in insufficient support strength. . Therefore, during roadway construction, it is necessary to find out the lithological characteristics of the roadway roof in time, and change the support method or adjust the support parameters in time fo...

AI Technical Summary

Problems solved by technology

The core method is to use the geological core drill to take the core of the roof, and analyze the lithological characteristics of the roof according to the columnar structure of the core. Use anytime and anywhere; the borehole wall impression method is to use some non-flowing and elastic plastic materials to fit on the surface of the borehole, copy the internal contour of the borehole under test into a mold, and then measure the impression to evaluate the borehole under test The internal structure of the borehole, but it cannot measure the lithological characteristics of the roof, and cannot provide scientific and effective data for the design of the support method; the borehole wall observation method uses equipment such as rock formation detection recorders to view the internal scene of the borehole through the probe. It was directly photographed, but due to the influence of the underground environment of the coal mine, this method has a low accuracy of peeking, and the error of the parameters of the roof surrounding rock structure obtained by this method is relatively large; the geological radar detection is based on the electrical difference of the probed medium. Electromagnetic technology for precise discrimination and positioning of the interface, this method does not reveal the development of joints and fissures enough, and cannot effectively identify the lithological characteristics of the roadway roof stratum, which is the focus and difficulty in the design and construction of roadway support

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