Underground tunneling space stability monitoring method and monitoring system

Abstract

The application relates to the technical field of underground tunneling space construction, and discloses a kind of underground tunneling space stability monitoring method and monitoring system, the monitoring method comprises: obtaining the deformation allowable value S y , the accumulated convergence deformation amount S x of similar rock mass before instability, the ultimate tensile value F L of anchor rod / anchor cable in rock mass;Continuously detect the convergence deformation amount S m of rock mass, the longitudinal wave transmission speed V n of rock mass, the tension value F i of anchor rod / anchor cable, wherein m, n, i are all natural numbers greater than 0;Calculate the convergence deformation early warning value S J of rock mass, the tensile early warning value F J of anchor rod / anchor cable, the convergence deformation early warning coefficient K s of rock mass, the tension change rate K F of anchor rod / anchor cable, the wave speed early warning coefficient K v of rock mass;When S m >1.25S J Or K S >1.2, or K v <0.7 and V n <2.5km / s, or F i =0 or K F >=1.2, output the information of rock mass instability.The monitoring method can detect the stability of underground tunneling space, especially the stability near the position of blasting surface, and further guarantee the construction safety.

Description

Technical Field

[0001] This invention relates to the field of underground tunneling space construction technology, specifically to a method and system for monitoring the stability of underground tunneling spaces. Background Technology

[0002] The stability of underground tunnels, chambers, and stopes is a fundamental safety guarantee for mine construction and production. In tunnels and stopes with frequent personnel movement, accurately measuring the stability of the working space is crucial to preventing roof collapse accidents. Currently, the stability of underground spaces is mostly assessed through experience. Some mines install ground pressure monitoring systems, but these systems have a limited number of sensors and can only determine the stability of the entire area based on data from test points. Furthermore, these monitoring devices are often deployed in stopes with long mining cycles for long-term monitoring; however, in tunnels and access-type stopes with short mining cycles, sensors placed too close to the working face are easily damaged. Roof collapse accidents often occur at or near the tunneling face. Therefore, although existing ground pressure monitoring systems exist, they are generally applicable to areas far from the tunneling face. Summary of the Invention

[0003] This invention was made to solve the above-mentioned technical problems. Its purpose is to provide a method and system for monitoring the stability of underground tunneling space, which can detect the stability of underground tunneling space, especially the stability near the blasting face, thereby ensuring construction safety.

[0004] To achieve the above objectives, the present invention provides a method for monitoring the stability of underground tunneling spaces, comprising the following steps:

[0005] Step S1: Obtain the allowable deformation value S of the rock mass within the underground excavation space. y The cumulative convergent deformation S before the rock mass instability described in the same category x The ultimate tensile strength F of the anchor bolt / anchor cable in the rock mass L ;

[0006] Step S2: Continuously monitor the convergence deformation S of the rock mass. m The longitudinal wave propagation velocity V of the rock mass n The tensile force F of the anchor bolt / anchor cable i , where m, n, and i are all natural numbers greater than 0;

[0007] Step S3: Calculate the early warning value S of the convergence deformation of the rock mass. J The tensile warning value F of the anchor bolt / anchor cable J The convergence deformation early warning coefficient K of the rock mass s The rate of change of tension K of the anchor bolt / anchor cable FThe wave velocity warning coefficient K of the rock mass v ,in

[0008] S J =0.8×min(S) y ,S x ),

[0009] F J =0.9F L ,

[0010]

[0011] V0 is the longitudinal wave propagation velocity of the rock mass measured for the first time;

[0012] Step S4, in the S m >1.25S J or K S When >1.2, or the aforementioned K v <0.7 and V n When <2.5km / s, or the aforementioned F i =0 or K F When the value is ≥1.2, output information about the instability of the rock mass.

[0013] To achieve the above objectives, in another aspect, the present invention provides an underground tunneling space stability monitoring system for performing the aforementioned underground tunneling space stability monitoring method, comprising:

[0014] A 3D laser scanner is installed inside the underground excavation space to inspect the 3D model of the underground excavation space.

[0015] Online anchor bolt / anchor cable force gauges are installed on anchor bolts / anchor cables within the underground excavation space to monitor the tension of anchor bolts / anchor cables in real time;

[0016] The acoustic wave tester has its probe installed in a test hole in the rock mass of the underground excavation space to detect the longitudinal wave transmission speed of the rock mass.

[0017] The data processor receives detection data from the 3D laser scanner, the online anchor bolt / anchor cable force gauge, and the acoustic wave tester, and calculates the S. J F J K s K F and K v It also outputs the stability information of the underground excavation space.

[0018] Based on the above description and practice, it can be seen that the underground tunneling space stability monitoring method of the present invention detects the convergence deformation S of the rock mass within the underground tunneling space.m Longitudinal wave propagation velocity V of the rock mass n The tensile force F of the anchor bolt / anchor cable i This allows for the analysis of rock mass stability. Furthermore, the equipment used to detect these parameters is unaffected by the blasting surface, enabling the monitoring of rock mass stability near the blasting surface and ultimately ensuring construction safety. Attached Figure Description

[0019] Figure 1 This is a flowchart of an underground tunneling space stability monitoring method according to one embodiment of the present invention. Detailed Implementation

[0020] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be more comprehensive and complete, and will fully convey the concept of exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0021] This embodiment discloses a method for monitoring the stability of underground tunneling spaces, used to detect the stability of underground tunneling spaces, such as monitoring the stability of tunneling roadways, chambers, and mining areas, where stability mainly refers to the stability of the surrounding rock mass of the underground tunneling space. Figure 1 As shown, the method for monitoring the stability of underground tunneling spaces mainly includes the following four steps:

[0022] Step S1: Obtain the allowable deformation value S of the rock mass within the underground excavation space. y The cumulative convergent deformation S of the same type of rock mass before instability x The ultimate tensile strength F of the anchor bolts / cables in the rock mass. L .

[0023] Among them, the allowable deformation value S of the rock mass y= W × M, where W is the width of the underground excavation space and M is the allowable convergence value around the underground excavation space. Once the size of the underground excavation space is determined, the value of W is known. The value of M can then be determined based on the type of rock mass surrounding the underground excavation space. Specifically, M can be determined based on the rock mass type and uniaxial compressive strength, as detailed in Table 1, where M is expressed as a percentage (%). For example, when the rock mass type surrounding the underground excavation space is Type III and the uniaxial compressive strength is 50 MPa, the allowable convergence value around the underground excavation space is 0.8% to 1.2%. More specifically, the data in this table applies to underground excavation spaces below 300m. For brittle rock masses, the smaller value within the range in Table 1 is taken as the M value; for ductile rock masses, the larger value within the range in Table 1 is taken as the M value.

[0024] Table 1:

[0025]

[0026]

[0027] The cumulative convergent deformation S of the same type of rock mass before instability x Data can be obtained by querying existing data, or by taking samples within the underground excavation space for actual measurement. For example, actual measurement can be performed by installing a convergence meter at a selected location within the underground excavation space, monitoring it over a long period, and recording the convergence data in a table to obtain the cumulative convergence deformation before the rock mass becomes unstable.

[0028] The ultimate tensile strength F of the anchor bolts / cables in this rock mass L Alternatively, it can be obtained through actual measurement. For example, after the support is completed in the underground excavation space, a pull-out test can be performed on some of the anchor bolts / cables to measure their ultimate tensile value F. L .

[0029] Step S2: Continuously monitor the convergence deformation S of the rock mass. m The longitudinal wave propagation velocity V of the rock mass n The tensile force F of the anchor bolt / anchor cable i , where m, n, and i are all natural numbers greater than 0, and m, n, and i represent the values ​​of each measurement. For example, S2 is the convergence deformation of the rock mass in the second measurement, and S4 is the convergence deformation of the rock mass in the fourth measurement.

[0030] Among them, the convergence deformation S of the rock mass is detected. mThis can be achieved using 3D laser scanning equipment. For example, a 3D laser scanner is placed at a fixed location in the underground tunneling space. The space is then periodically scanned to acquire point cloud data. This point cloud data processing software is then used to obtain a 3D model of the underground tunneling space. The subsequently scanned 3D model is then compared with the initial scanned model. For areas where the changes exceed a preset range, cross-sections are extracted to obtain the contour of the rock mass in the underground tunneling space at that cross-section. Comparing the contours of each cross-section in the two models reveals the convergence deformation S at each point. m .

[0031] The longitudinal wave propagation velocity V of the rock mass was detected. n During this process, wave velocity test holes with a depth of 3-4m can be set up in each tunneling cycle in the underground tunneling space, and the probe of the surrounding rock acoustic wave tester can be placed in the test hole. Then, the longitudinal wave transmission velocity V of the rock mass at that location can be measured using the single-hole acoustic wave method. n The testing frequency is once every 1-3 days, in S m and F i When the change in the quantity shows an increasing trend, a test needs to be conducted once a day.

[0032] When testing the tension value F of anchor bolts / anchor cables i At that time, the tension value F of the anchor bolt / anchor cable can be monitored in real time using an online anchor bolt / anchor cable force gauge. i The detection data is transmitted to the back-end data processor in real time for data processing. At least one of these online anchor bolt / anchor cable force gauges is deployed in each tunneling cycle in the underground tunneling space to ensure timely monitoring of the rock mass stability in each tunneling cycle.

[0033] The above provides the values ​​for detecting the convergence deformation S of the rock mass. m The longitudinal wave propagation velocity V of the rock mass n The tensile force F of the anchor bolt / anchor cable i In one method, in other embodiments, the user may also use other existing devices to detect these data, such as using a multi-point displacement meter to measure the convergence deformation, which can also achieve data acquisition.

[0034] Step S3: Calculate the early warning value S of the convergence deformation of the rock mass. J Tensile warning value F of anchor bolts / anchor cables J Rock mass convergence deformation early warning coefficient K s The rate of change of tension K of the anchor bolt / anchor cable F The wave velocity warning coefficient K of the rock mass v ,in

[0035] S J =0.8×min(S) y ,Sx ),

[0036] F J =0.9F L ,

[0037]

[0038] In the formula, V0 is the longitudinal wave propagation velocity of the rock mass measured for the first time.

[0039] Among them, the early warning value S of the convergence deformation of the rock mass is calculated. J When, take S y and S x The minimum value is 80% of the minimum value. Obtaining this warning value provides a reference basis for subsequent monitoring of the convergence deformation of the rock mass. Two warning values ​​S J and F J It provides users with two parameters that can monitor the stability of underground tunneling spaces.

[0040] Rock mass convergence deformation early warning coefficient K s The wave velocity warning coefficient K of the rock mass represents the rate of change of the convergence deformation of the rock mass. v These values ​​indicate the degree of change in the longitudinal wave transmission velocity of the rock mass. When these values ​​exceed a certain range, it means that the rock mass is deformed significantly and the stability of the underground excavation space is poor.

[0041] The calculations in this step can be performed by a data processor, such as a computer with built-in calculation programs.

[0042] Step S4: Output the stability information of the underground excavation space based on the above calculation results.

[0043] Specifically, in S m >1.25S J or K S When >1.2, or the aforementioned K v <0.7 and V n When <2.5km / s, or the aforementioned F i =0 or K F When S ≥ 1.2, information about rock mass instability is output. m >1.25S J or K S A value greater than 1.2 indicates a large or rapid change in the convergence deformation of the rock mass, implying a high probability of instability. When the rock mass is relatively stable, its longitudinal wave propagation velocity is typically not lower than 2.5 km / s. v <0.7 and V nA velocity <2.5 km / s indicates a low and highly variable P-wave propagation velocity in the rock mass, suggesting a significant possibility of instability. i When K = 0, it indicates that the tension of the anchor bolt / cable is zero, meaning that the anchor bolt / cable has lost its supporting function, possibly due to deformation at some point in the rock mass. This also indicates a high probability of rock mass instability. F A value ≥1.2 indicates a significant change in the tension of the anchor bolt / anchor cable, which may be due to deformation at some point in the rock mass, and also indicates a high probability of rock mass instability.

[0044] In addition, if the tested data do not meet the above conditions, the following condition shall apply: S J <S m ≤1.25S J And K S =1.2, or 2.5km / s≤V n <3.5km / s and K v When ≥0.7, or F i >F J And 1 < K F When S < 1.2, the output indicates moderate stability of the rock mass. J <S m ≤1.25S J And K S When V = 1.2, it indicates that although the convergence deformation of the rock mass exceeds the warning value, the rate of change of the convergence deformation is 1.2, meaning that the deformation of the rock mass is relatively stable and still within a controllable range; 2.5 km / s ≤ V n <3.5km / s and K v When the value is ≥0.7, it indicates that although the longitudinal wave propagation velocity of the rock mass varies considerably, it is still within a controllable range; F i >F J And 1 < K F When the value is less than 1.2, it indicates that although the tension of the anchor bolt / cable exceeds the warning value, the rate of change of the tension is still low and within a controllable range, meaning that the rock mass is still relatively stable. In these cases, the output should indicate that the rock mass is moderately stable.

[0045] Furthermore, if the tested data still do not meet the above conditions, then if the following condition is met: S m <S J And K S When <1.2, and V n ≥3.5km / s and 0.7≤K v When <1, and F i ≤F J And K F When S ≤ 1, the rock mass stability information is output. m <SJ And K S When V < 1.2, it indicates that the convergence deformation of the rock mass has not exceeded the warning value, and the rate of change of the convergence deformation is less than 1.2, meaning that the rock mass is stable; n ≥3.5km / s and 0.7≤K v When F < 1, it indicates that the longitudinal wave propagation velocity of the rock mass is relatively high and the degree of change is relatively low, which means that the rock mass is stable; i ≤F J And K F When the value is ≤1, it means that the tension of the anchor bolt / anchor cable has not exceeded the warning value and the rate of change of the tension is still very low, which means that the rock mass is stable.

[0046] The stability information output above can be implemented in one or more forms, such as video, images, sound, and light.

[0047] In this embodiment, an underground tunneling space stability monitoring system is also disclosed for performing the above-described underground tunneling space stability monitoring method. The monitoring system includes: a three-dimensional laser scanner, an online anchor bolt / anchor cable force gauge, an acoustic wave tester, and a data processor.

[0048] The 3D laser scanner is positioned at a predetermined location within the underground excavation space to detect its 3D model. Even when positioned far from the blasting face, it can still measure the 3D model of the underground excavation space, avoiding damage during blasting operations. The 3D laser scanner is pre-installed with point cloud data processing software. The scanner's detection data can be directly processed to generate a 3D model of the underground excavation space, which is then transmitted to a data processor for further data processing and analysis. Alternatively, the data processor can have pre-installed point cloud data processing software, allowing the 3D laser scanner to directly transmit the detection data to the processor, which then converts it into a 3D model. Finally, the data processor calculates the convergence deformation S of the rock mass. m Convergence deformation warning value S J And the convergence deformation early warning coefficient K of the rock mass s .

[0049] Online anchor bolt / cable force gauges are installed on anchor bolts / cables within the underground excavation space. These anchor bolts / cables are used to support the underground excavation space and improve its stability. The online anchor bolt / cable force gauges can monitor the tension value F of the anchor bolts / cables in real time. i This online anchor bolt / cable force gauge connects to a data processor, enabling real-time transmission of detection data for subsequent processing. Located on the anchor bolt / cable and protected by the anchor hole, the online force gauge is minimally affected even when close to the blasting surface, facilitating user monitoring of rock stability near the blasting area.

[0050] The probe of the acoustic wave tester is installed in a test hole in the rock mass of the underground tunneling space to detect the longitudinal wave propagation velocity of the rock mass. The test hole is located within each tunneling cycle, at a depth of 3–4 meters. With the probe inside the test hole, the main testing equipment and other devices can be positioned at a distance from the blasting face via a data cable, reducing the impact of blasting operations. The acoustic wave tester is also connected to a data processor, enabling real-time transmission of the detection data for subsequent data processing.

[0051] The data processor can be a terminal device with computing capabilities, such as a server, smartphone, tablet, laptop, or desktop computer. It has a pre-installed calculation program that, after receiving detection data from a 3D laser scanner, an online anchor bolt / cable force gauge, and an acoustic wave tester, executes the calculation program to calculate the convergence deformation warning value S of the rock mass according to the method described in step S3 above. J Tensile warning value F of anchor bolts / anchor cables J Rock mass convergence deformation early warning coefficient K s The rate of change of tension K of the anchor bolt / anchor cable F The wave velocity warning coefficient K of the rock mass v It should be noted that the known parameter is the allowable deformation value S of the rock mass. y The cumulative convergent deformation S of the same type of rock mass before instability x and the ultimate tensile strength F of the anchor bolt / anchor cable in the rock mass L The data can be input by the user into the data processor. Additionally, the data processor has a pre-installed analysis program. When this program executes, it can derive the stability information of the rock mass based on the calculation results and the analysis method described in step S4. Finally, this stability information is output.

[0052] Specifically, the data processor can be equipped with one or more devices such as a built-in display, audio player, and indicator lights, so as to output the stability information of the rock mass in the form of video, images, sound, and light for users to obtain.

[0053] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for monitoring the stability of underground tunneling spaces, characterized in that, include: Step S1: Obtain the allowable deformation value S of the rock mass within the underground excavation space. y The cumulative convergent deformation S before the rock mass instability described in the same category x The ultimate tensile strength F of the anchor bolt / anchor cable in the rock mass L ; Step S2: Continuously monitor the convergence deformation S of the rock mass. m The longitudinal wave propagation velocity V of the rock mass n The tensile force F of the anchor bolt / anchor cable i Where m, n, and i are all natural numbers greater than 0; and the tension value F of the anchor bolt / anchor cable is monitored in real time by an online anchor bolt / anchor cable force gauge. i The detection data is transmitted to the background data processor in real time; The three-dimensional model of the underground tunneling space is detected by a three-dimensional laser scanning device. By comparing the subsequently detected three-dimensional model with the initially detected three-dimensional model, the convergence deformation S of the rock mass can be obtained. m In each tunneling cycle of the underground tunneling space, a wave velocity testing hole with a depth of 3-4m is provided, and the probe of the surrounding rock acoustic wave tester is placed in the testing hole. The longitudinal wave transmission velocity V of the rock mass is measured using the single-hole acoustic wave method. n ; Step S3: Calculate the early warning value S of the convergence deformation of the rock mass. J The tensile warning value F of the anchor bolt / anchor cable J The convergence deformation early warning coefficient K of the rock mass s The rate of change of tension K of the anchor bolt / anchor cable F The wave velocity warning coefficient K of the rock mass v ,in ， ， ， ， ， V0 is the longitudinal wave propagation velocity of the rock mass measured for the first time; Step S4, in the At that time, or as stated At that time, or as stated At that time, information about the instability of the rock mass is output.

2. The method for monitoring the stability of underground tunneling space as described in claim 1, characterized in that, The allowable deformation value of the rock mass Where W is the width of the underground excavation space, and M is the allowable convergence value around the underground excavation space.

3. The method for monitoring the stability of underground tunneling space as described in claim 1, characterized in that, In step S2, the longitudinal wave propagation velocity V of the rock mass is detected every 1-3 days. n .

4. The method for monitoring the stability of underground tunneling space as described in claim 1, characterized in that, At least one of the online anchor bolt / anchor cable force gauges shall be arranged in each tunneling cycle of the underground tunneling space.

5. The method for monitoring the stability of underground tunneling space as described in claim 1, characterized in that, In dissatisfaction At that time, or as stated At that time, or as stated hour, If the above At that time, or as stated and At that time, or At that time, information on the moderate stability of the rock mass is output.

6. An underground tunneling space stability monitoring system, used to execute the underground tunneling space stability monitoring method as described in any one of claims 1-5, characterized in that, include: A 3D laser scanner is installed inside the underground excavation space to inspect the 3D model of the underground excavation space. Online anchor bolt / anchor cable force gauges are installed on anchor bolts / anchor cables within the underground excavation space to monitor the tension of anchor bolts / anchor cables in real time; The acoustic wave tester has its probe installed in a test hole in the rock mass of the underground excavation space to detect the longitudinal wave transmission speed of the rock mass. The data processor receives detection data from the 3D laser scanner, the online anchor bolt / anchor cable force gauge, and the acoustic wave tester, and calculates the S. J F J K s K F and K v It also outputs the stability information of the underground excavation space.

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