SU1467177A1 - Method of monitoring the state of working-face in the process of hydraulic rock excavation - Google Patents

Abstract

The invention relates to mining. The goal is to increase the information content of the control. Acoustic sigals generated by the action of hydraulic jets on the array are recorded and analyzed. Additionally, acoustic emission signals are recorded. The amplitude, intensity, and spectral densities of the acoustic emission signals and acoustic signals are measured. cash. The latter are generated by the action of a hydraulic jet on the array. According to the characteristics obtained, the rock crushability of the fracture, the intensity of the fracture, the individual stages of the hydraulic structure, the position of the sources of destruction and the location of the meeting of the hydraulic jet with the bottom hole are determined. The method allows to improve the performance of the hydraulic excavation. 2 Il. &

Description

The invention relates to mining and is intended to determine bottomhole parameters. characteristics of the process of hydraulic destruction during hydraulic excavation of rocks.

The purpose of the invention is to increase the information content of the control ..

Figure 1 shows the installation of receivers with hydraulic openings in short air; Fig. 2 shows the same with hydraulic openings with long refining faces.

Figures 1 and 2 denote rock mass G, hydro monitor 2, acoustic sensors (receivers) 3, excavation production 4, mechanized complex 5, excavation unit 6, ventilation 7 and co-firing 8 drifts.

In addition, in FIG. shows the contour of the ABCD., and in FIG. 2 -. pressure support zone R.

The method is carried out in the following way.

In the excavation excavation 4 (Fig. 1), the hydrometer nitor 2 is installed at: a distance of 3–5 m from the boundary of the goaf (line BC). The contour to be excavated zajkk ABCD. The long working face (lava) is equipped with a mechanized complex 5 and a excavation unit 6 (Fig. 2). In the ventilation 7 and conveyor 8 drifts, receivers 3 are installed,

Acoustic signals arising from the destruction of rocks hydravCD

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acoustic emission signals are received at the receivers 3 and, after amplification, are separated by a filter unit into components: acoustic emission signals C4 (frequencies about 5 kHz) and signals generated by the actual hydraulic impact on array C. up to 1-3 kHz). Next, Q determines the amplitudes of signals C and C, their intensity and spectral density.

The measurement results are sent to comparison blocks in which the amplitude, intensity, and spectral density of the signals are compared with similar parameters of the calibration signals. The spectral density comparison results are 20 estimates of the resistance of an array to fracture. The results of the comparison of the amplitude of the signal C with the amplitude of the calibration signal are compared with the results of the comparison of the 25 amplitudes of the signal Cj (perceived by the same receiver) with the amplitude of the corresponding calibration signal, on the basis of which the hydraulic depths are determined. A comparison of the intensity and amplitude of the signal C ,, perceived at the breaking stage, with the corresponding parameters of the calibration signal, makes it possible to estimate the intensity of fracture. At the stages of attenuation and blasting, the relative attenuation of the amplitude of signals Cj, perceived by the various-receivers, is determined, which makes it possible to find the coordinates of the meeting place of the jetting station with the face. On one hundred days of breaking, the time delay of signals C, perceived by various receivers, is determined, the amplitude selection of these signals is made, on the basis of which the numbers of caKf tori of the array correspond to the location of the existing foci of destruction, Thus, the proposed method; it allows you to control the following parameters of the state of the slaughter and the process of hydraulic destruction of the resistance; the fracture rocks, separate stages of the hydraulic structure, the intensity of the hydraulic destruction, the location of the foci of destruction and the meeting point of the jetting jet with the bottom, can be used as a basis for the manufacture of the electrical measuring complex

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Standard instruments used to measure and record acoustic emission parameters, as well as elements of sound-absorbing equipment of the SCT type, should be taken.

The physical prerequisites for the implementation of the proposed control method are as follows.

The resistance of rocks to hydraulic fracture is estimated when the jet moves in contact with the face at a certain speed along the bottom surface. Over a period of 5-10 seconds, enough information is gathered to estimate the spectral density of the acoustic signals, and with the help of the latter Comparison with preliminary calibration data performed on an array with known resistance is estimated by hydraulic fracture rock resistance. The method of separating the hydraulic stages is based on the use of the following characteristic features of the recorded acoustic signals. Small shark: The tic activity of the rock to be destroyed is characteristic of the initial stage of destruction (weakening). The stage of hydroturbing corresponds to the process of avalanche propagation of cracks, which is accompanied by a sharp increase in the intensity and amplitude of acoustic emission signals C. Signals C in the attenuation and breaking stages are strong enough in amplitude; at the stage of disconnection and reduction of the amplitude of signals C and C2. and the intensity of the signals C fall significantly,

The increase in the intensity and amplitude of the acoustic emission signals (s,) corresponds to the increase in the intensity of the hydraulic destruction. The measurement of the intensity of the hydraulic destruction is most justified to be carried out at the breaking stage (with the greatest acoustic activity of the rock).

The position of the source of destruction can be determined by the difference in the time of reception of the same signal With receivers located at different distances from the source of signals at the stage of the most intensive crack growth (breaking).

In order to separate the coordinates of the foci of destruction, it is necessary to make an amplitude selection of the signals Cj, which

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Claims (1)

Claim A method for monitoring the state of a face during hydraulic excavation of rocks, including recording and analyzing acoustic signals generated by the action of a hydraulic jet on an array, characterized in that, in order to increase the information content of the control, acoustic emission signals are additionally recorded, and amplitudes and intensities are measured and spectral densities of acoustic emission signals and acoustic signals generated by the action of a hydraulic jet on the array, and by; The irradiated characteristics determine the resistance of rocks to hydraulic fracture, the rate of hydraulic fracture, individual stages of hydraulic excavation, the location of the foci of destruction and the place where the hydraulic jet meets the face. FIG. 2