Rock mass fracture zone stress-strain real-time monitoring method and rock mass stability analysis method

Abstract

The application discloses a rock mass fracture zone stress and strain real-time monitoring method and a rock mass stability analysis method. The real-time monitoring method comprises the following steps: determining a fracture zone surface region; vertically digging a groove along the middle position of the fracture zone surface region, the groove extending through the fracture zone surface region to the complete rock mass regions on both sides; burying a preset stress monitoring device in the groove; determining first drilling hole position information and second drilling hole position information according to the groove, and drilling a first mounting hole and a second mounting hole; respectively installing a first anchor rod and a second anchor rod in the first mounting hole and the second mounting hole, and the first anchor rod and the second anchor rod are both provided in a cantilevered manner; installing a preset strain monitoring device between the cantilevered first anchor rod and the second anchor rod; and acquiring stress information and strain information of the fracture zone region based on the preset stress monitoring device and the preset strain monitoring device. The method can realize real-time monitoring of the stress and deformation in the fracture zone, and provides a basis for surrounding rock control.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of rock mass stress and strain monitoring, and particularly relates to a rock mass fracture zone stress and strain real-time monitoring method and a rock mass stability analysis method. BACKGROUND

[0002] During the excavation of a deep vertical shaft, surrounding rocks of different integrity are generated; the displacements and stress changes of rock layers of different integrity are inconsistent; when the surrounding rocks of two different integrity are combined together, the complete surrounding rock and the fracture zone will appear inconsistent deformation; if the shaft is affected by the inconsistent deformation for a long time, the shaft wall will crack, and in a more serious case, the shaft wall will be unstable.

[0003] Due to the geological structure, the fractured surrounding rock has developed cracks, and the engineering characteristics have non-homogeneity, non-continuity and uncertainty. After the underground engineering is excavated, the distribution range of the exposed fractured surrounding rock also has uncertainty; the fractured rock mass surrounding rock may be only centimeters, or may reach several meters or even tens of meters. The conventional stress and strain monitoring means disclosed in the prior art cannot meet the accurate monitoring demand of the pressure deformation of the fractured surrounding rock. SUMMARY

[0004] Therefore, the embodiments of the present disclosure provide a rock mass fracture zone stress and strain real-time monitoring method and a rock mass stability analysis method, which can realize real-time, comprehensive and accurate monitoring of the stress and strain of the discovered rock mass fracture zone on site, and are fast and efficient.

[0005] In a first aspect, the embodiments of the present disclosure provide a rock mass fracture zone stress and strain real-time monitoring method, which comprises the following steps:

[0006] According to the on-site information of the rock mass, the surface area of the fracture zone is determined.

[0007] A groove is vertically excavated along the middle position of the surface area of the fracture zone, and the groove extends through the surface area of the fracture zone to the complete rock mass area on both sides.

[0008] A preset stress monitoring device is buried in the groove, and is fixed by covering with concrete.

[0009] According to the groove, first drilling position information and second drilling position information are determined.

[0010] First and second installation holes are drilled according to the first and second drilling position information respectively; the center line of the first and second installation holes is parallel to the longitudinal axis of the groove, and the first installation hole is perpendicular to the surface of the fracture zone.

[0011] First and second anchor rods are installed in the first and second installation holes respectively, and the first and second anchor rods are both provided in a cantilevered manner.

[0012] The preset strain monitoring device is installed between the first anchor rod and the second anchor rod, and a longitudinal axis of the preset strain monitoring device is perpendicular to the first anchor rod.

[0013] The stress information of the fracture zone is obtained based on the preset stress monitoring device, and the strain information of the fracture zone is obtained based on the preset strain monitoring device.

[0014] Optionally, an inner diameter of the groove is matched with an outer diameter of the preset stress monitoring device, and a length of the groove is greater than a vertical dimension of the fracture zone surface area.

[0015] The vertical direction is a longitudinal stress direction in which the fracture zone surface area spreads to the intact rock mass.

[0016] Optionally, the groove is vertically opened along the middle position of the fracture zone surface area, and the groove comprises:

[0017] A groove body is vertically opened along the middle position of the fracture zone surface area, and a length of the groove body is not less than a vertical dimension of the fracture zone surface area.

[0018] A first groove and a second groove are respectively opened at two ends of the groove body, and an inner diameter of the first groove and an inner diameter of the second groove are both greater than an inner diameter of the groove body.

[0019] The first groove is located in an intact rock mass area on one side of the fracture zone surface area, and the second groove is located in an intact rock mass area on the other side of the fracture zone surface area.

[0020] Optionally, the preset stress monitoring device comprises a round steel, a first base, a second base, and a stress monitoring device fixed to the round steel, the first base and the second base are respectively fixedly installed at two ends of the round steel, and end area of the first base and the second base are both greater than end area of the round steel.

[0021] The preset stress monitoring device is buried in the groove, and the method comprises:

[0022] The round steel is placed in the groove body.

[0023] The first base and the second base are respectively placed in the first groove and the second groove.

[0024] Optionally, a hole depth of the first mounting hole, a hole depth of the second mounting hole, and a groove depth of the groove are uniformly set.

[0025] The preset stress monitoring device is provided in plurality.

[0026] When the preset stress monitoring device is provided with three, the preset stress monitoring device is buried in the groove and fixed by covering with concrete, comprising:

[0027] The first preset stress monitoring device is arranged at the bottom of the groove and covered with concrete;

[0028] The second preset stress monitoring device is arranged in the groove after covering with concrete along the depth direction of the groove and covered with concrete;

[0029] The third preset stress monitoring device is arranged in the groove after covering with concrete along the depth direction of the groove and covered with concrete;

[0030] The three preset stress monitoring devices are arranged at equal intervals along the depth direction of the groove.

[0031] Optionally, the distance from the outer side of the third preset stress monitoring device to the surface area of the fracture zone is ΔH, 10cm≤ΔH≤20cm.

[0032] Optionally, the first drilling position information comprises a first drilling position, a first hole depth and a first hole diameter; and the second drilling position information comprises a second drilling position, a second hole depth and a second hole diameter.

[0033] The distance between the first drilling position and the groove is L1, 10cm≤L1≤20cm.

[0034] The distance between the second drilling position and the first drilling position is matched with the length of the preset strain monitoring device.

[0035] The first hole diameter is matched with the outer diameter of the first anchor rod.

[0036] The second hole diameter is matched with the outer diameter of the second anchor rod.

[0037] Optionally, the distance from the preset strain monitoring device to the surface area of the fracture zone is L3, 3cm≤L3≤5cm.

[0038] Optionally, the first base and the second base are arranged in the same structure.

[0039] The stress information of the fracture zone area comprises the stress P in the rock mass: P=F / A; wherein F is the pressure value detected by the preset stress monitoring device, and A is the area of the first base.

[0040] In a second aspect, the application discloses a rock mass stability analysis method, based on the rock mass fracture zone stress and strain real-time monitoring method, comprising:

[0041] acquire stress information of the broken zone region in a preset period based on the preset stress monitoring device;

[0042] acquire a stress change trend graph according to the stress information in the preset period;

[0043] acquire strain information of the broken zone region in a preset period based on the preset strain monitoring device;

[0044] acquire a strain change trend graph according to the strain information in the preset period;

[0045] determine the influence of the surface region of the broken zone on the sidewall of the roadway based on the stress change trend graph and the strain change trend graph.

[0046] The rock mass broken zone stress and strain real-time monitoring method disclosed in the present application can directly acquire stress information of the broken zone region by digging a groove in the surface region of the broken zone and burying a stress monitoring device therein. Meanwhile, the strain information of the broken zone region can be monitored in real time by drilling installation holes on both sides of the groove and installing anchor rods in combination with a strain monitoring device, so that the stress and strain changes of the broken surrounding rock can be captured more accurately, and the problem that the stress and strain of the broken surrounding rock cannot be accurately monitored in the prior art can be solved. By monitoring the broken zone region specifically, the mechanical behavior of the region can be grasped more accurately. Monitoring stress and strain can comprehensively evaluate the stability of the rock mass from multiple angles. Real-time monitoring equipment can acquire data in time and respond to possible changes quickly. By burying and fixing the monitoring device, the continuity and reliability of the data can be ensured. Through real-time monitoring of the broken zone, potential risks can be warned in advance, and the safety of personnel and equipment can be ensured.

[0047] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the content of the specification can be implemented, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creating any creative labor.

[0049] Figure 1 The flowchart of the rock mass broken zone stress and strain real-time monitoring method provided by the embodiments of the present application is shown.

[0050] Figure 2The installation schematic diagram of the preset stress monitoring device provided by the embodiment of the present disclosure.

[0051] Figure 3 The installation schematic diagram of the preset stress monitoring device provided by the embodiment of the present disclosure.

[0052] Figure 4 The flowchart of the rock mass stability analysis method provided by the embodiment of the present disclosure.

[0053] Explanation of reference signs:

[0054] 10, upper intact rock mass; 20, surface area of fracture zone; 30, lower intact rock mass; 100, first base; 200, round steel; 300, second base; 400, stress monitoring device; 500, first anchor rod; 600, second anchor rod; 700, preset stress monitoring device. DETAILED DESCRIPTION

[0055] The embodiments of the present disclosure are described in detail below with reference to the drawings.

[0056] It should be apparent that the following describes embodiments of this disclosure by way of specific examples, and that one of ordinary skill in the art can readily derive further advantages and effects of this disclosure from the disclosure. Obviously, the described embodiments are only a part of the embodiments of this disclosure, not all. This disclosure can also be implemented or applied by other different specific embodiments, and the details in this specification can be modified or changed based on different views and applications without departing from the spirit of this disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in this disclosure, all other embodiments obtained by one of ordinary skill in the art without creative labor are within the scope of protection of this disclosure.

[0057] It should be noted that the various aspects of the embodiments described below are within the scope of the appended claims. It should be apparent that the aspects described herein can be embodied in a wide variety of forms and that any specific structure and / or function described herein is merely illustrative. Based on the disclosure, one of ordinary skill in the art should understand that one aspect described herein can be implemented independently of any other aspect, and that two or more of these aspects can be combined in various ways. For example, an apparatus can be implemented using any number of the aspects described herein. In addition, this apparatus and / or method can be implemented using other structures and / or functionality in addition to or other than one or more of the aspects described herein.

[0058] It is also necessary to note that the drawings provided in the following embodiments only illustrate the basic concept of the present disclosure in a schematic manner, and only the components related to the present disclosure are shown in the drawings, not the number, shape and size of the components when actually implemented, and the actual implementation of each component can be a random change, and the component layout pattern can be more complex.

[0059] In addition, in the following description, specific details are provided in order to facilitate a thorough understanding of the examples. However, one skilled in the art will understand that the aspects described can be practiced without these specific details.

[0060] Reference Figure 1 The present application discloses a real-time monitoring method for stress and strain of rock mass fracture zone, comprising:

[0061] S100, determining the surface area of the fracture zone according to the field information of the rock mass.

[0062] Specifically, the specific location and range of the surface area of the fracture zone can be determined by a geological engineer or relevant professional on-site investigation according to the field information of the rock mass; determining the surface area of the fracture zone ensures that the monitoring target is clear.

[0063] S200, vertically excavating a groove along the middle position of the surface area of the fracture zone, the groove extending through the surface area of the fracture zone to the intact rock mass area on both sides.

[0064] The purpose of this groove is to bury the stress monitoring device, and by extending to the intact rock mass area, the stability and reliability of the monitoring data are ensured.

[0065] By excavating a groove in the middle position of the surface area of the fracture zone, the concentrated stress caused by external stress can be effectively dispersed and absorbed, reducing the impact of stress concentration on the structure, and this design helps to improve the overall stability of the structure, especially in the area of the fracture zone which may have unstable factors; At the same time, the middle position is selected because the stress distribution is representative and can reflect the stress condition of the entire fracture zone.

[0066] In this step, the groove is excavated to bury the stress monitoring device, and the extension to the intact rock mass area enhances the stability.

[0067] S300, burying the preset stress monitoring device in the groove and covering and fixing it with concrete.

[0068] Wherein, the inner diameter of the groove is matched with the outer diameter of the preset stress monitoring device, and the length of the groove is greater than the vertical dimension of the surface area of the fracture zone; the vertical direction is the longitudinal stress direction of the surface area of the fracture zone spreading to the intact rock mass.

[0069] The distance from the outer side of the preset stress monitoring device to the surface area of the fracture zone is △H, and 10 cm≤△H≤20 cm.

[0070] Specifically, the preset stress monitoring device includes a round steel, a first base, a second base, and a stress monitoring device fixed to the round steel. The first base and the second base are respectively fixed and installed at two ends of the round steel, and the end area of the first base and the second base is greater than the end area of the round steel.

[0071] Specifically, the round steel is vertically placed in the groove, and then covered and fixed with concrete (i.e., the groove is filled), to ensure the stable installation of the preset stress monitoring device, i.e., to ensure that it is closely combined with the rock mass, and at the same time, to protect these devices from external interference or damage, so as to obtain accurate stress data.

[0072] Through this step, it can be ensured that the arrangement of the preset stress monitoring device covers the entire range from the fracture zone to the complete rock mass area on both sides, providing comprehensive stress data to help engineers more accurately assess the health status of the structure.

[0073] S400, according to the groove, determining first drilling position information and second drilling position information.

[0074] Among the two first drilling position information and the second drilling position information, the drillings are parallel.

[0075] S500, drilling a first installation hole and a second installation hole according to the first drilling position information and the second drilling position information respectively; the center line of the first installation hole and the second installation hole is parallel to the longitudinal axis of the groove, and the first installation hole is perpendicular to the surface of the fracture zone.

[0076] Meanwhile referring to Figure 2 The distance between the first drilling position and the groove is L1, and 10 cm≤L1≤20 cm.

[0077] The first drilling position information includes a first drilling position, a first hole depth, and a first hole diameter; and the second drilling position information includes a second drilling position, a second hole depth, and a second hole diameter.

[0078] S600, installing a first anchor rod and a second anchor rod in the first installation hole and the second installation hole respectively, and the first anchor rod and the second anchor rod are both overhangingly arranged.

[0079] Specifically, one end of the first anchor rod is fixedly installed with the first installation hole, which can play a fixing and supporting role on the part overhanging out of the first installation hole; one end of the second anchor rod is fixedly installed with the second installation hole, which can play a fixing and supporting role on the part overhanging out of the second installation hole.

[0080] The first hole diameter is matched with the outer diameter of the first anchor rod, and the second hole diameter is matched with the outer diameter of the second anchor rod.

[0081] The first hole diameter is matched with the outer diameter of the first anchor rod, and the second hole diameter is matched with the outer diameter of the second anchor rod.

[0082] S700, the preset strain monitoring device is installed between the first anchor rod and the second anchor rod, and the longitudinal axis of the preset strain monitoring device is perpendicular to the first anchor rod.

[0083] In this step, the two anchor rods are anchored in the corresponding drill holes in a full-length anchoring manner, the part of the anchor rod exposed from the shelter is not fixed so that the strain of the fractured rock mass can be detected, and the preset strain monitoring device is welded between the two anchor rods to monitor the strain of the fractured rock mass in real time.

[0084] Specifically, the preset strain monitoring device can be welded and fixed with the first anchor rod and the second anchor rod.

[0085] Referring to FIG. 3, the distance between the second drill hole position and the first drill hole position is matched with the length of the preset strain monitoring device 700.

[0086] The distance from the preset strain monitoring device 700 to the surface area 20 of the fractured zone is L3, and 3cm≤L3≤5cm.

[0087] The overhanging part of the first anchor rod 500 and the second anchor rod 600 can provide an installation base point for the strain monitoring device, facilitating fixed installation. Meanwhile, the preset strain monitoring device 700 is installed between the overhanging first anchor rod 500 and the second anchor rod 600, and the longitudinal axis of the device is perpendicular to the first anchor rod 500. This installation mode can ensure that the strain monitoring device can measure strain along a specific direction, thereby obtaining accurate deformation data.

[0088] S800, based on the preset stress monitoring device, stress information of the fractured zone is obtained; based on the preset strain monitoring device, strain information of the fractured zone is obtained.

[0089] Specifically, the data transmission lines of the preset stress monitoring device and the preset strain monitoring device can be connected to a multi-channel data acquisition instrument to obtain real-time stress and strain information of the fractured rock mass.

[0090] The rock mass fracture zone stress-strain real-time monitoring method disclosed by the application can directly obtain stress information of the fracture zone region by digging a groove in the surface region of the fracture zone and burying a stress monitoring device in the groove; at the same time, the strain information of the fracture zone region can be monitored in real time by drilling installation holes on both sides of the groove and installing anchor rods, combined with the strain monitoring device, so that the stress-strain change of the fractured surrounding rock can be captured more accurately, and the problem that the stress-strain of the fractured surrounding rock cannot be accurately monitored in the prior art is solved. By monitoring the fracture zone region, the mechanical behavior of the region can be more accurately grasped; at the same time, stress and strain are monitored, the stability of the rock mass can be comprehensively evaluated from multiple angles; real-time monitoring equipment is used, data can be obtained in time, and possible changes can be responded quickly; by burying and fixing the monitoring device, the continuity and reliability of the data are ensured; through real-time monitoring of the fracture zone, potential risks can be warned in advance, and the safety of personnel and equipment is ensured.

[0091] Further, with reference to Figure 2 , the groove is vertically dug along the middle position of the surface region of the fracture zone 20, which specifically can include: a groove main body is vertically dug along the middle position of the surface region of the fracture zone 20; the length of the groove main body is not less than the vertical dimension of the surface region of the fracture zone 20; a first groove and a second groove are respectively dug at both ends of the groove main body, and the inner diameters of the first groove and the second groove are both greater than the inner diameter of the groove main body, which can adapt to the stress distribution under different geological conditions.

[0092] Among them, the first groove is located in the complete rock mass area on one side of the surface region of the fracture zone 20; the second groove is located in the complete rock mass area on the other side of the surface region of the fracture zone 20, that is, the first groove is located in the upper complete rock mass 10, and the second groove is located in the lower complete rock mass 30.

[0093] In the upper complete rock mass 10 and the lower complete rock mass 30, the relatively large inner diameter can better adapt to the possible large stress change here because the rock is relatively solid; and in the fracture zone region, the relatively small inner diameter of the groove main body can more effectively disperse the stress.

[0094] The preset stress monitoring device 400 is buried in the groove, including: placing the round steel 200 in the groove main body; placing the first base 100 and the second base 300 in the first groove and the second groove respectively.

[0095] Among them, the stress monitoring device 400 is preferably located at the middle of the round steel 200.

[0096] In this embodiment, the hole depth of the first installation hole, the hole depth of the second installation hole, and the groove depth of the groove are set uniformly.

[0097] The first base and the second base are arranged in the same structure; the stress information of the fracture zone area includes the stress P inside the rock mass: P=F / A; wherein F is the pressure value detected by the preset stress monitoring device, and A is the area of the first base.

[0098] The structural design of the groove makes the installation and maintenance of the monitoring device more convenient; due to the design of the groove body and the two end grooves, the preset stress monitoring device can be easily placed in place, and when it needs to be replaced or checked, it can also be easily taken out and reinstalled, which greatly reduces the difficulty and time of maintenance.

[0099] In another embodiment, the preset stress monitoring device can be provided with multiple.

[0100] When the preset stress monitoring device is provided with three, the preset stress monitoring device is buried in the groove and fixed by covering with concrete, comprising:

[0101] A100, the first preset stress monitoring device is arranged at the bottom of the groove and covered with concrete;

[0102] A200, the second preset stress monitoring device is arranged in the groove covered with concrete along the groove depth direction, and covered with concrete;

[0103] A300, the third preset stress monitoring device is arranged in the groove covered with concrete along the groove depth direction, and covered with concrete;

[0104] The three preset stress monitoring devices are arranged at equal intervals along the groove depth direction.

[0105] In this embodiment, the distance from the outside of the third preset stress monitoring device to the surface area YY+242358P

[0106] of the fracture zone is △H, and 10cm≤△H≤20cm.

[0107] In this embodiment, three round steels in the three preset stress monitoring devices are arranged in parallel; by arranging multiple stress monitoring devices in the groove, the stress distribution of the fracture zone can be more comprehensively monitored, and different depths of monitoring devices can capture stress changes at different positions, thereby providing more detailed data; the stress distribution inside the fracture zone may be uneven, and the stress changes near the surface and deep regions may be different; by arranging multiple monitoring devices at different depths, the stress state inside the fracture zone can be comprehensively reflected, avoiding the limitations of single-point monitoring; the arrangement of multiple monitoring devices can verify the data with each other, reducing errors or abnormalities that may occur in single-point monitoring; when the monitoring results of multiple devices tend to be consistent, the reliability and accuracy of the data can be improved; by arranging multiple monitoring devices at equal intervals along the groove depth direction, the stress distribution changes inside the fracture zone can be dynamically monitored; this is very important for analyzing the stress change trend of surrounding rock and judging whether there is a stress concentration or instability risk; multiple monitoring devices arranged at equal intervals can facilitate data analysis and comparison; stress changes at different depths can be used to evaluate the stability of surrounding rock and provide a basis for construction and reinforcement measures; the equal interval arrangement method can be adjusted according to specific engineering needs; for example, if the fracture zone is deep, the number of monitoring devices can be increased to further refine the monitoring points to adapt to more complex geological conditions.

[0108] By arranging multiple preset stress monitoring devices at equal intervals along the groove depth direction in the groove, fine monitoring of the stress inside the fracture zone can be achieved, which can improve the accuracy and reliability of the monitoring data, comprehensively reflect the stress distribution of the fracture zone, and provide more accurate basis for engineering design and construction, thereby enhancing the safety and stability of the project.

[0109] In the existing wellbore excavation process, there may be incoordination deformation between intact surrounding rock and fracture zone, which can lead to well wall cracking and even instability over a long period of time; by monitoring the stress and strain information of the fracture zone area in real time, the incoordination deformation of the surrounding rock can be found in time, thereby providing a basis for dynamic adjustment of engineering design. For example, reinforcement measures such as increasing support or adjusting the excavation schedule can be taken in advance to avoid well wall instability.

[0110] The distribution range and properties of fractured surrounding rock are uncertain, which may vary from a few centimeters to tens of meters; this scheme can adapt to fractured surrounding rock of different ranges and properties by excavating a groove in the surface area of the fracture zone and burying monitoring devices therein.

[0111] The rock mass fracture zone stress-strain real-time monitoring method disclosed in the application has simple installation hole and anchor rod design, can be quickly installed and adjusted, and is suitable for different engineering environments and geological conditions. Meanwhile, the layout of the monitoring device can be expanded according to the actual situation to ensure the comprehensiveness and flexibility of the monitoring; through real-time monitoring, potential safety hazards can be found in time to avoid the occurrence of shaft wall cracking and instability, thereby reducing engineering accidents and maintenance costs; based on the monitoring data, the shaft excavation design and construction scheme can be optimized to reduce unnecessary engineering costs and improve construction efficiency and economic benefits; the scheme not only monitors stress but also obtains strain information through the strain monitoring device, and the combination of the two can more comprehensively reflect the stress state of the surrounding rock and improve the integrity and accuracy of the monitoring data.

[0112] The rock mass fracture zone stress-strain real-time monitoring method disclosed in the application has clear steps, including grooving, burying the monitoring device, and drilling the installation hole, and the operation process is simple and easy to implement, which is convenient for engineering and technical personnel to implement. The scheme is not only suitable for deep vertical shaft excavation but also can be popularized to other underground engineering such as tunnels and mines, and has a wide application prospect.

[0113] The rock mass fracture zone stress-strain real-time monitoring method disclosed in the application solves the problems of shaft wall cracking and instability caused by incoordination deformation of fractured surrounding rock in the deep vertical shaft excavation process through innovative monitoring device layout and accurate stress-strain monitoring. The advantage is that it can accurately monitor complex geological conditions, dynamically adjust engineering design, and improve engineering safety and economy, and the operation is simple and easy to popularize and apply.

[0114] Reference Figure 4 In the second aspect, the application discloses a rock mass stability analysis method based on the rock mass fracture zone stress-strain real-time monitoring method, comprising:

[0115] S10, obtaining stress information in a preset period in the fracture zone region based on a preset stress monitoring device.

[0116] By regularly obtaining stress information, the stress change of the fracture zone region can be monitored in real time, and abnormal conditions can be found in time; continuously collecting stress data provides sufficient data basis for subsequent trend analysis and stability evaluation; stress data at multiple depths helps to understand the distribution and variation law of stress in the fracture zone.

[0117] S20, obtaining a stress change trend graph according to the stress information in the preset period.

[0118] Specifically, the stress data of each depth obtained in S10 can be subjected to time series analysis, and a stress change curve of each monitoring point over time can be drawn. For example, a line chart can be drawn using Excel or professional software (such as MATLAB, Origin, etc.), with the horizontal axis representing time and the vertical axis representing stress value.

[0119] The stress change trend chart intuitively shows the change of stress over time, facilitating observation and analysis; through the trend chart, the change trend of stress, such as whether it is continuously increasing, fluctuation amplitude, etc., can be identified, which helps to predict possible risks; the trend charts of multiple monitoring points can be compared to understand the similarities and differences of stress changes at different depths.

[0120] S30, obtaining strain information of the fracture zone region in a preset period based on the preset strain monitoring device.

[0121] The strain information can reflect the deformation of the surrounding rock, and in combination with the stress information, the mechanical state of the rock mass can be more comprehensively evaluated; the strain data are directly related to the deformation degree of the rock mass, which is crucial for evaluating the wellbore stability.

[0122] S40, obtaining a strain change trend chart according to the strain information in the preset period.

[0123] The strain change trend chart can show the development trend of the rock mass deformation, helping to judge whether over-deformation occurs; sudden increase of strain can be a precursor of wellbore instability, and through the trend chart, early warning can be made.

[0124] S50, determining the influence of the fracture zone surface region on the roadway sidewall based on the stress change trend chart and the strain change trend chart.

[0125] The change trends of stress and strain are comprehensively analyzed to evaluate the potential influence of the fracture zone on the roadway sidewall. For example, if the stress and strain continuously increase, it can indicate that the pressure of the fracture zone on the sidewall increases, and there is a risk of instability; according to the analysis results, it can be decided whether reinforcement measures need to be taken. Through comprehensive analysis of the stress and strain trends, the stability influence of the fracture zone on the roadway sidewall can be accurately evaluated, potential risks can be found in time, scientific basis can be provided for engineering design and construction, appropriate support measures can be guided to be taken, and engineering safety can be ensured.

[0126] The rock mass stability analysis method disclosed in the application provides a comprehensive view of the mechanical behavior of the rock mass by simultaneously monitoring stress and strain; in combination with the change trend of stress and strain, the stability of the rock mass can be more accurately evaluated; potential instability signs are found in advance, preventive measures are taken in time, and safety accidents are avoided; the engineering design is adjusted based on actual monitoring data, and the economy and efficiency of the engineering are improved; the method is applicable to various complex geological conditions and has a wide application prospect. The rock mass stability analysis method of the application provides strong technical support for underground engineering construction by real-time monitoring and comprehensive analysis of stress and strain data, effectively ensuring the safety and stability of the engineering.

[0127] Further, if there is a target turning point in the strain curve of the strain change trend graph, it is determined that the influence of the surface area of the fracture zone on the sidewall of the roadway is serious, which means that continuing construction can lead to a large deformation of the roadway, and therefore the construction will be suspended and comprehensive support of the sidewall of the roadway will be carried out.

[0128] If the trend of the stress change trend graph and the strain change trend graph is consistent, it is determined that the influence of the surface area of the fracture zone on the sidewall of the roadway is not large, and the construction can continue.

[0129] Further, according to the strain change trend graph, the change rate of strain with time (i.e. strain rate) can be obtained, and the change trend thereof is analyzed. The strain rate can be obtained by derivation with respect to time, and the formula is: strain rate = d∈ / dt, wherein ∈ is strain and t is time.

[0130] Under normal circumstances, the strain change of the rock mass is slow and stable, and the strain rate is usually low and stable; when the strain rate suddenly increases (i.e. the slope of the strain curve suddenly changes), it indicates that the surrounding rock may enter an unstable state, and such sudden change is usually caused by stress concentration of the surrounding rock, rock mass rupture or support failure, etc.

[0131] On the stress-strain curve, a sudden change in the slope (i.e. the curve becomes steep) indicates an increase in the strain rate, indicating that the surrounding rock is about to lose stability; by monitoring the change in the strain rate, the risk of surrounding rock instability can be warned in advance, so that support measures can be taken in time.

[0132] Through strain measurement, the deformation of the surrounding rock can be mastered in real time, and abnormalities can be found in time; the sudden change in the strain rate is a precursor of the instability of the surrounding rock, which can provide an early warning signal for support decision-making; by analyzing the change in the strain rate, the best support timing can be determined, and premature or late support can be avoided.

[0133] According to the stress change trend chart, the stability of the surrounding rock can be evaluated. If the measured stress value is lower than the bearing capacity of the rock mass, the surrounding rock is in a stable state. If the stress value is close to or exceeds the bearing capacity, the surrounding rock may enter the plastic deformation stage and there is a risk of instability. Through stress information, the stress distribution of the surrounding rock can be calculated, for example, high stress areas may be concentrated in certain parts of the roof or sidewall of the roadway.

[0134] Combined with stress information and the mechanical parameters of the rock mass (such as elastic modulus, Poisson's ratio, etc.), the plastic zone range of the rock mass can be calculated through numerical analysis (such as finite element analysis). The appearance of the plastic zone indicates that the rock mass has entered the nonlinear deformation stage and may require reinforced support.

[0135] By comprehensively analyzing the strain and stress data, the overall stability of the surrounding rock can be evaluated by combining the strain rate trend and stress distribution. Numerical analysis tools (such as finite element software) can be used to calibrate model parameters based on monitoring data to simulate the stress distribution and deformation behavior of the surrounding rock. Through the simulation results, the reliability of the monitoring data can be further verified, and the support scheme can be optimized.

[0136] If the strain rate increases and the stress value is close to or exceeds the bearing capacity, it indicates that the surrounding rock may be about to lose stability. If the strain rate is stable and the stress value is low, it indicates that the surrounding rock is in a stable state.

[0137] For the determination of support timing: when the strain rate suddenly increases, support measures need to be taken immediately; when the stress value is close to the bearing capacity, support needs to be strengthened in advance.

[0138] The selection of support methods can be determined according to the numerical analysis results, such as the selection of support methods (such as anchor support, shotcrete support, etc.) and support strength. For high stress areas or plastic zones, stronger support measures (such as increasing the density of anchor rods or using high-strength shotcrete) need to be taken.

[0139] By comprehensively analyzing the strain and stress data, the support timing and support method can be scientifically determined to avoid blind support. The numerical analysis results provide a basis for the optimization of the support scheme, which can improve the support effect and reduce the engineering cost. Through real-time monitoring and scientific analysis, the stability of the surrounding rock can be effectively prevented, and the safety of the roadway construction and operation can be ensured.

[0140] The basic principles of the present disclosure are described above in conjunction with specific embodiments, but it should be noted that the advantages, advantages, effects, etc. mentioned in the present disclosure are only examples and not limitations, and these advantages, advantages, effects, etc. cannot be considered as necessary for each embodiment of the present disclosure. In addition, the above specific details are only for the purpose of example and understanding, and are not limited to the above specific details for the implementation of the present disclosure.

[0141] In this disclosure, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The block diagrams of devices, apparatuses, devices, and systems involved in this disclosure are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as "comprising," "including," "having," etc., are open-ended terms meaning "including but not limited to," and are used interchangeably with them. The terms "or" and "and" as used herein refer to the terms "and / or," and are used interchangeably with them unless the context clearly indicates otherwise. The term "such as" as used herein refers to the phrase "such as but not limited to," and is used interchangeably with it.

[0142] Additionally, as used herein, the “or” used in a list of items beginning with “at least one” indicates a separate list, such that a list of, for example, “at least one of A, B, or C” means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word “exemplary” does not imply that the described example is preferred or better than other examples.

[0143] It should also be noted that in the systems and methods of this disclosure, the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalent solutions to this disclosure.

[0144] Various changes, substitutions, and modifications can be made to the technology described herein without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of this disclosure is not limited to the specific aspects of the processes, machines, manufactures, events, means, methods, and actions described above. Currently existing or later-developed processes, machines, manufactures, events, means, methods, or actions that perform substantially the same function or achieve substantially the same result as the corresponding aspects described herein can be utilized. Therefore, the appended claims include such processes, machines, manufactures, events, means, methods, or actions within their scope.

[0145] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0146] The foregoing description has been presented for the purposes of illustration and description. Furthermore, the description is not intended to limit the embodiments of the disclosure to the forms disclosed herein. Although the various example aspects and embodiments have been described herein with regard to particular aspects and embodiments, those skilled in the art will recognize that certain modifications, changes, substitutions, additions and sub-combinations can be made without departing from the spirit of the disclosure.

Claims

1. A method for real-time monitoring of stress and strain in fractured rock masses, characterized in that, include: Based on the on-site information of the rock mass, the surface area of ​​the fracture zone was determined: A vertical groove is excavated along the middle of the surface area of ​​the fractured zone, and the groove extends through the surface area of ​​the fractured zone to the intact rock mass areas on both sides; The pre-set stress monitoring device is embedded in the groove and fixed with concrete; Based on the groove, the first borehole position information and the second borehole position information are determined; The first mounting hole and the second mounting hole are drilled according to the first drilling position information and the second drilling position information, respectively; the center line connecting the first mounting hole and the second mounting hole is parallel to the longitudinal axis of the groove, and the first mounting hole is perpendicular to the surface of the crushed zone; The first anchor rod and the second anchor rod are respectively installed in the first mounting hole and the second mounting hole, and both the first anchor rod and the second anchor rod are suspended. A preset strain monitoring device is installed between the cantilevered first anchor rod and the second anchor rod, with the longitudinal axis of the preset strain monitoring device perpendicular to the first anchor rod; The stress information of the fracture zone area is obtained based on the preset stress monitoring device; The strain information of the fracture zone region is obtained based on the preset strain monitoring device.

2. The method for real-time monitoring of stress and strain in fractured rock mass zones according to claim 1, characterized in that, The inner diameter of the groove is matched with the outer diameter of the preset stress monitoring device, and the length of the groove is greater than the vertical dimension of the surface area of ​​the broken zone; The vertical direction refers to the longitudinal stress direction that extends from the surface region of the fractured zone to the intact rock mass.

3. The method for real-time monitoring of stress and strain in fractured rock mass zones according to claim 2, characterized in that, The vertically chiseled groove along the middle position of the surface area of ​​the fracture zone includes: A groove body is vertically formed at the middle position of the surface area of ​​the crushing zone; the length of the groove body is not less than the vertical dimension of the surface area of ​​the crushing zone; A first groove and a second groove are respectively opened at both ends of the groove body, and the inner diameter of the first groove and the inner diameter of the second groove are both larger than the inner diameter of the groove body. The first groove is located in the intact rock mass area on one side of the surface region of the fracture zone; the second groove is located in the intact rock mass area on the other side of the surface region of the fracture zone.

4. The method for real-time monitoring of stress and strain in fractured rock mass zones according to claim 3, characterized in that, The preset stress monitoring device includes a round steel bar, a first base, a second base, and a stress monitoring device fixed to the round steel bar. The first base and the second base are respectively fixedly installed at both ends of the round steel bar, and the end areas of the first base and the second base are both larger than the end area of ​​the round steel bar. The step of embedding the preset stress monitoring device in the groove includes: Place the round steel bar into the main body of the groove; Place the first base and the second base into the first slot and the second slot, respectively.

5. The method for real-time monitoring of stress and strain in fractured rock mass zones according to claim 4, characterized in that, The depths of the first mounting hole, the second mounting hole, and the groove are all set to be the same; Multiple preset stress monitoring devices are provided; When three preset stress monitoring devices are installed, the step of embedding the preset stress monitoring devices in the groove and fixing them with concrete includes: The first preset stress monitoring device is fitted into the bottom of the groove and covered with concrete; A second preset stress monitoring device is installed in the groove along the groove depth direction after the concrete is used for covering; A third preset stress monitoring device is installed in the groove after the concrete is used to cover it, along the groove depth direction. The three preset stress monitoring devices are arranged at equal intervals along the groove depth direction.

6. The method for real-time monitoring of stress and strain in fractured rock mass according to claim 5, characterized in that, The distance from the outer side of the third preset stress monitoring device to the surface area of ​​the fracture zone is ΔH, where 10cm≤ΔH≤20cm.

7. The method for real-time monitoring of stress and strain in fractured rock mass according to claim 5, characterized in that, The first borehole location information includes a first borehole location, a first borehole depth, and a first borehole diameter; the second borehole location information includes a second borehole location, a second borehole depth, and a second borehole diameter. The distance between the first drilled hole and the groove is L1, where 10cm≤L1≤20cm; The distance between the second borehole position and the first borehole position is set to match the length of the preset strain monitoring device; The first aperture is matched with the outer diameter of the first anchor rod; The second aperture is matched with the outer diameter of the second anchor rod.

8. The method for real-time monitoring of stress and strain in fractured rock mass according to claim 7, characterized in that, The distance from the preset strain monitoring device to the surface area of ​​the fracture zone is L3, where 3cm≤L3≤5cm.

9. The method for real-time monitoring of stress and strain in fractured rock mass according to claim 4, characterized in that, The first base and the second base have the same structure. The stress information of the fracture zone includes the stress P inside the rock mass: P = F / A; where F is the pressure value detected by the preset stress monitoring device, and A is the area of ​​the first base.

10. A method for analyzing rock mass stability, characterized in that, The method for real-time monitoring of stress and strain in fractured rock mass according to any one of claims 1-9 includes: Based on the preset stress monitoring device, stress information within a preset period in the fracture zone area is obtained; Based on the stress information within a preset period, obtain a stress change trend diagram; Based on the preset strain monitoring device, strain information within a preset period in the fracture zone area is obtained; Based on the strain information within a preset period, obtain a strain change trend diagram; Based on the stress change trend diagram and the strain change trend diagram, the influence of the fractured zone surface area on the roadway sidewall is determined.

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