Method for testing disturbance stress of tunnel surrounding rock

Abstract

The application provides a tunnel surrounding rock disturbance stress testing method, comprising the following steps: obtaining the rock mass basic quality grade of the tunnel surrounding rock of a tunnel to be monitored; according to the rock mass basic quality grade of the tunnel surrounding rock, a plurality of disturbance stress testing drill holes are arranged on the tunnel surrounding rock; a plurality of stress sensors are arranged in the disturbance stress testing drill holes at intervals; and stress monitoring information of each stress sensor is obtained. The method can understand the rock mass mechanical properties of the tunnel surrounding rock to be monitored by obtaining the rock mass basic quality grade of the tunnel surrounding rock, so that the disturbance stress testing drill holes are arranged according to the rock mass basic quality grade of the tunnel surrounding rock, a plurality of disturbance stress testing drill holes are arranged on the tunnel surrounding rock, and the arrangement mode of the disturbance stress testing drill holes can have higher adaptability and pertinence to the rock mass mechanical properties of the tunnel surrounding rock, the influence of the tunnel rock mass mechanical properties on the monitoring cost is reduced, the accuracy of the stress monitoring result of the key area is improved, and reliable basis is provided for the stability evaluation of the tunnel surrounding rock.

Description

Technical Field

[0001] This invention relates to the field of surrounding rock stress testing technology, and in particular to a method for testing the disturbance stress of surrounding rock in tunnels. Background Technology

[0002] In related technologies, in order to monitor the disturbance stress on the surrounding rock of a tunnel and to analyze and evaluate the stability of the surrounding rock based on the monitoring data, stress monitoring is usually carried out by uniformly arranging measuring holes and stress sensors on the surrounding rock around the tunnel according to the structural parameters of the tunnel cross section. However, the aforementioned testing method can easily lead to a significant increase in testing costs or result in inaccurate stability evaluation results. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] In view of this, a method for testing the disturbance stress of tunnel surrounding rock is proposed according to an embodiment of this application, comprising:

[0005] Obtain the basic quality grade of the surrounding rock mass of the tunnel to be monitored;

[0006] Based on the basic quality grade of the surrounding rock mass of the tunnel, multiple disturbance stress test boreholes were drilled in the surrounding rock of the tunnel.

[0007] Multiple stress sensors are spaced out in each disturbance stress test borehole;

[0008] Obtain stress monitoring information from each stress sensor.

[0009] In one feasible implementation, the aforementioned step of drilling multiple disturbance stress test boreholes in the tunnel surrounding rock according to the basic quality grade of the surrounding rock mass includes:

[0010] Select a stress monitoring section, which is perpendicular to the tunnel's axial direction;

[0011] Based on the basic quality grade of the surrounding rock mass of the tunnel, the layout of multiple disturbance stress test boreholes is determined.

[0012] Based on the borehole layout and stress monitoring section, multiple disturbance stress test boreholes are drilled in the surrounding rock of the tunnel. The axes of these multiple disturbance stress test boreholes are all located within the stress monitoring section.

[0013] In one feasible implementation, the aforementioned step of determining the layout of multiple disturbance stress test boreholes based on the basic rock mass quality grade of the tunnel surrounding rock includes:

[0014] Based on the stress monitoring section, determine the height line and span line of the tunnel to be monitored;

[0015] Obtain the height h and span l of the tunnel to be monitored;

[0016] A polar coordinate system is established with the intersection of the elevation line and the span line as the pole, the ray originating from the pole and passing through the apex of the tunnel to be monitored as the polar axis, and the clockwise direction as the positive direction.

[0017] When the basic quality grade of the surrounding rock of the tunnel is Grade I, Grade II or Grade III, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the form of the first borehole layout.

[0018] Among them, multiple disturbance stress test boreholes include top test holes, first side test holes, and first shoulder test holes, and the first hole layout is as follows:

[0019] A top measuring hole with a depth of 3h is opened on the surrounding rock of the tunnel along the first preset angle direction, where the first preset angle direction is greater than or equal to -10° and less than or equal to 10°.

[0020] Along the second preset angle direction, a first side measuring hole with a depth of 4l is opened on the surrounding rock of the tunnel. The second preset angle direction is greater than or equal to 85° and less than or equal to 95°.

[0021] Along the third preset angle direction, a first shoulder measuring hole with a depth of 1.5(l+h) is opened on the surrounding rock of the tunnel. The third preset angle direction is greater than or equal to -45° and less than or equal to -30°.

[0022] In one feasible implementation, the aforementioned step of determining the layout of multiple disturbance stress test boreholes based on the basic quality grade of the surrounding rock mass of the tunnel further includes:

[0023] When the basic quality grade of the surrounding rock of the tunnel is Class IV, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the first and second borehole layouts.

[0024] Among them, multiple disturbance stress test boreholes also include second side test holes and second shoulder test holes, and the second hole layout is as follows:

[0025] Along the fourth preset angle direction, a second shoulder measuring hole with a depth of 1.5(l+h) is opened on the surrounding rock of the tunnel. The fourth preset angle is greater than or equal to 30° and less than or equal to 45°.

[0026] Along the fifth preset angle direction, a second side measuring hole with a depth of 4l is opened on the surrounding rock of the tunnel. The fifth preset angle direction is greater than or equal to -95° and less than or equal to -85°.

[0027] In one feasible implementation, the aforementioned step of determining the layout of multiple disturbance stress test boreholes based on the basic quality grade of the surrounding rock mass of the tunnel further includes:

[0028] When the basic quality grade of the surrounding rock of the tunnel is Grade V, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the first, second and third borehole layouts.

[0029] Among them, the multiple disturbance stress test boreholes also include a first bottom test hole and a second bottom test hole, and the third hole layout is as follows:

[0030] Along the sixth preset angle direction, a first bottom measuring hole with a depth of (l+h) is opened on the surrounding rock of the tunnel. The sixth preset angle direction is greater than or equal to 135° and less than or equal to 150°.

[0031] Along the seventh preset angle direction, a second bottom measuring hole with a depth of (l+h) is opened on the surrounding rock of the tunnel. The seventh preset angle direction is greater than or equal to -150° and less than or equal to -135°.

[0032] In one feasible implementation, the spacing between stress sensors is increased along the direction from the borehole opening to the bottom of each disturbance stress test borehole.

[0033] In one feasible implementation, the method for testing the disturbance stress of tunnel surrounding rock further includes:

[0034] Obtain the monitoring time information of each stress sensor;

[0035] Based on stress monitoring information and monitoring time information, the primary relationship between surrounding rock stress and monitoring duration is determined.

[0036] In one feasible implementation, the method for testing the disturbance stress of tunnel surrounding rock further includes:

[0037] Obtain the measurement point location information of each stress sensor;

[0038] Based on stress monitoring information and measuring point location information, a second relationship is determined between the surrounding rock stress and the borehole depth of the disturbance stress test borehole.

[0039] In one feasible implementation, the method for testing the disturbance stress of tunnel surrounding rock further includes:

[0040] Based on the stress monitoring information and monitoring time information of each stress sensor, the stress duration curve of each stress sensor is determined, and the stress duration curve is used to determine the first relationship;

[0041] Based on stress monitoring information and measurement point location information, stress-depth curves are established for each disturbance stress test borehole. These stress-depth curves are used to determine the second relationship.

[0042] In one feasible implementation, the method for testing the disturbance stress of tunnel surrounding rock further includes:

[0043] Based on the stress-hole depth curve, the critical stress point of the tunnel surrounding rock is determined. The critical stress point is the first peak point in the stress-hole depth curve along the direction of increasing hole depth.

[0044] Based on the critical stress point, the damage and fracture zone and the elastic zone of the tunnel surrounding rock are determined.

[0045] Based on the stress-duration curve, the self-stabilization duration of the surrounding rock and the support stabilization duration of the surrounding rock are determined.

[0046] Compared with the prior art, the present invention has at least the following beneficial effects: The tunnel surrounding rock disturbance stress testing method provided in this application obtains the basic quality grade of the surrounding rock of the tunnel to be monitored; based on the basic quality grade of the surrounding rock, multiple disturbance stress testing boreholes are drilled in the surrounding rock; multiple stress sensors are arranged at intervals in each disturbance stress testing borehole; and the stress monitoring information of each stress sensor is obtained. Before stress monitoring of the surrounding rock, by obtaining the basic quality grade of the surrounding rock, the mechanical properties of the surrounding rock can be understood, thereby allowing for the determination of the basic quality grade of the surrounding rock. To assess the impact of rock mass on monitoring costs, multiple disturbance stress test boreholes are drilled in the tunnel surrounding rock. This ensures that the arrangement of these boreholes is highly adaptable and targeted to the rock mechanics properties of the tunnel surrounding rock, thereby improving the accuracy of stress monitoring results in key areas. Furthermore, multiple stress sensors are spaced out within each disturbance stress test borehole to monitor the stress on the tunnel surrounding rock near each borehole. By acquiring stress monitoring information from these sensors, a reliable basis for the stability analysis and evaluation of the tunnel surrounding rock is provided. Attached Figure Description

[0047] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of exemplary embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0048] Figure 1 A schematic flowchart illustrating a method for testing disturbance stress in tunnel surrounding rock according to an embodiment of this application;

[0049] Figure 2 This is a schematic structural diagram of the borehole layout for the disturbance stress test boreholes determined by the tunnel surrounding rock disturbance stress test method according to an embodiment of this application.

[0050] Figure 3This is a schematic structural diagram of the borehole layout for the disturbance stress test borehole determined by the tunnel surrounding rock disturbance stress test method according to another embodiment of this application.

[0051] Figure 4 This is a schematic structural diagram of the borehole layout for the disturbance stress test boreholes determined by the tunnel surrounding rock disturbance stress test method according to another embodiment of the present application.

[0052] Figure 5 This is a schematic diagram of the arrangement of stress sensors in the top measuring hole, determined by a tunnel surrounding rock disturbance stress testing method according to an embodiment of this application.

[0053] Figure 6 This is a schematic diagram of the arrangement of stress sensors in the test hole of the tunnel wall, determined by a method for testing disturbance stress in the surrounding rock of a tunnel according to an embodiment of this application.

[0054] Figure 7 This is a schematic diagram of the arrangement of stress sensors in the shoulder measuring hole, determined by a tunnel surrounding rock disturbance stress testing method according to an embodiment of this application.

[0055] Figure 8 This is a schematic diagram of the arrangement of stress sensors in the bottom measuring hole, as determined by a tunnel surrounding rock disturbance stress testing method according to an embodiment of this application.

[0056] Figure 9 This is a schematic diagram of the stress-time curve determined by a tunnel surrounding rock disturbance stress testing method according to an embodiment of this application;

[0057] Figure 10 This is a schematic diagram of the stress-hole depth curve determined by a tunnel surrounding rock disturbance stress testing method according to an embodiment of this application.

[0058] in, Figures 2 to 8 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0059] 10 tunnels to be monitored;

[0060] 100 Top measuring hole; 200 First shoulder measuring hole; 300 First side measuring hole; 400 Second shoulder measuring hole; 500 Second side measuring hole; 600 First bottom measuring hole; 700 Second bottom measuring hole. Detailed Implementation

[0061] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0062] According to an embodiment of this application, a method for testing the disturbance stress of surrounding rock in tunnels is proposed, such as... Figure 1 As shown, it includes:

[0063] Step S101: Obtain the basic quality grade of the surrounding rock of the tunnel to be monitored;

[0064] Specifically, the basic quality grade of rock mass can reflect the hardness and integrity of rock mass. Therefore, there is a close correlation between the basic quality grade of rock mass surrounding the tunnel and the bearing capacity of the tunnel surrounding rock. By obtaining the basic quality grade of rock mass surrounding the tunnel to be monitored, the mechanical properties of the rock mass surrounding the tunnel to be monitored can be understood, thus providing a reference for the arrangement of disturbance stress test boreholes.

[0065] Understandably, the basic quality grade of the surrounding rock of a tunnel can be determined according to the engineering rock mass classification standards, using the testing and evaluation methods provided in the standards, through methods such as exploration and sampling tests. The process of determining the basic quality grade of the surrounding rock of a tunnel will not be described in detail here. The engineering rock mass classification standards divide the basic quality of rock mass into five levels: Grade I, Grade II, Grade III, Grade IV, and Grade V. As the basic quality grade of the rock mass increases, the rock mass quality decreases.

[0066] Step S102: Based on the basic quality grade of the surrounding rock mass of the tunnel, multiple disturbance stress test boreholes are drilled in the surrounding rock of the tunnel.

[0067] Specifically, once the basic quality grade of the surrounding rock mass of the tunnel is obtained, the arrangement of disturbance stress test boreholes can be based on the basic quality grade of the surrounding rock mass. Multiple disturbance stress test boreholes can be opened on the surrounding rock mass to ensure that the arrangement of the disturbance stress test boreholes is highly targeted to the mechanical properties of the surrounding rock mass of the tunnel, thereby reducing the impact of the mechanical properties of the tunnel rock mass on monitoring costs and stress monitoring results.

[0068] Understandably, traditional techniques rely on the structural parameters of the tunnel cross-section. Measuring boreholes are uniformly arranged on the surrounding rock, and stress sensors are evenly placed within these boreholes to monitor stress in different sections of the tunnel. However, the rock mechanics properties of the surrounding rock are often overlooked during borehole placement. Consequently, when monitoring tunnels with relatively small cross-sections, the number of boreholes is often limited. If the surrounding rock quality is relatively poor, the limited coverage of the boreholes will result in missing stress monitoring data for certain sections. If the unmonitored areas contain fragile, easily damaged strata, subsequent analysis and evaluation of rock stability based on monitoring data may yield results inconsistent with the actual situation, hindering timely warnings of rock fracturing and instability. Conversely, when monitoring tunnels with relatively large cross-sections, a larger number of boreholes are used. If the surrounding rock quality is relatively good and the stress field distribution on both sides of the tunnel is relatively balanced, this leads to data redundancy, significantly increasing the cost of sensor and borehole placement, and consequently, the cost of testing for surrounding rock disturbance stress.

[0069] Compared to traditional testing methods, the tunnel surrounding rock disturbance stress testing method provided in this application takes the basic quality grade of the surrounding rock mass as a reference when arranging the disturbance stress testing boreholes. This considers the impact of the surrounding rock quality, allowing for a more dense and uniform arrangement of the boreholes when the surrounding rock quality is relatively poor, thus ensuring monitoring coverage. Conversely, a sparser arrangement can be used when the surrounding rock quality is also relatively poor, saving on borehole arrangement costs and reducing the number of stress sensors required. In other words, the location and number of disturbance stress testing boreholes are adjusted according to the basic quality grade of the surrounding rock mass, thereby improving the adaptability and specificity of the borehole arrangement to the mechanical properties of the surrounding rock mass.

[0070] In some feasible examples, during the drilling process of disturbance stress test boreholes, core drill bits can be used to open the holes, and pneumatic slag removal can be used to remove the slag formed during drilling, so as to improve the forming quality of disturbance stress test boreholes and provide further assurance for the accuracy of stress monitoring.

[0071] Step S103: Arrange multiple stress sensors at intervals in each disturbance stress test borehole;

[0072] Specifically, multiple stress sensors are arranged at intervals in each disturbance stress test borehole to monitor the stress on the surrounding rock of the tunnel near each disturbance stress test borehole. It can be understood that in the same disturbance stress test borehole, multiple stress sensors are arranged at intervals along the depth direction of the borehole.

[0073] In some feasible examples, the stress sensor is a three-dimensional stress sensor, which can be used to meet the stress testing requirements of the tunnel surrounding rock in different directions.

[0074] Step S104: Obtain stress monitoring information from each stress sensor.

[0075] Specifically, acquiring stress monitoring information from various stress sensors can provide reference data for subsequent stability analysis and evaluation of tunnel surrounding rock. Furthermore, since the quality of the tunnel surrounding rock is considered during the arrangement of disturbance stress test boreholes, the possibility of lack of monitoring in areas with poor rock mass quality can be reduced, improving the comprehensiveness of stress monitoring information coverage and providing a reliable basis for stability evaluation and damage early warning analysis of tunnel surrounding rock.

[0076] In summary, the tunnel surrounding rock disturbance stress testing method provided in this application, before conducting stress monitoring of the tunnel surrounding rock, obtains the basic quality grade of the surrounding rock mass, thereby understanding the rock mass mechanical properties of the surrounding rock to be monitored. Based on the basic quality grade of the surrounding rock mass, disturbance stress testing boreholes are arranged, and multiple disturbance stress testing boreholes are opened in the tunnel surrounding rock. This ensures that the arrangement of the disturbance stress testing boreholes is highly targeted to the rock mass mechanical properties of the tunnel surrounding rock, reducing the impact of the rock mass mechanical properties on monitoring costs and stress monitoring results. Furthermore, multiple stress sensors are spaced apart within each disturbance stress testing borehole to monitor the stress on the tunnel surrounding rock near each borehole. By acquiring the stress monitoring information from each stress sensor, a reliable basis is provided for the stability analysis and evaluation of the tunnel surrounding rock.

[0077] In some examples, the aforementioned step of drilling multiple disturbance stress test boreholes in the surrounding rock of the tunnel, based on the basic quality grade of the surrounding rock mass, includes:

[0078] Select a stress monitoring section, which is perpendicular to the tunnel's axial direction;

[0079] Based on the basic quality grade of the surrounding rock mass of the tunnel, the layout of multiple disturbance stress test boreholes is determined.

[0080] Based on the borehole layout and stress monitoring section, multiple disturbance stress test boreholes are drilled in the surrounding rock of the tunnel. The axes of these multiple disturbance stress test boreholes are all located within the stress monitoring section.

[0081] Specifically, in the process of drilling multiple disturbance stress test boreholes in the tunnel surrounding rock based on the basic quality grade of the surrounding rock, it is necessary to select the stress monitoring section and ensure that the stress monitoring section is perpendicular to the tunnel axis. This allows for the planning of the placement of the disturbance stress test boreholes based on the stress monitoring section. Simultaneously, the borehole layout is determined according to the basic quality grade of the tunnel surrounding rock. Furthermore, based on the borehole layout and the stress monitoring section, multiple disturbance stress test boreholes are drilled in the tunnel surrounding rock, ensuring that the axes of all the boreholes are located within the stress monitoring section. This avoids positional deviations between stress sensors along the tunnel axis when placing them within the boreholes, thus ensuring the reliability of the stress monitoring data and the accuracy of the tunnel surrounding rock stability analysis and evaluation.

[0082] It should be noted that, depending on the actual situation of the tunnel, for shorter tunnels, monitoring sections can be selected in the middle section of the tunnel's axis; for longer tunnels, since the area corresponding to the surrounding rock is relatively large, the rock mass quality sometimes exhibits uneven distribution along the tunnel's axis. Therefore, extensive rock mass surveys are often conducted before tunnel excavation. Based on the survey results, the distribution of the basic quality grade of the surrounding rock along the tunnel's axis can be obtained. Monitoring sections can then be selected in the section with the worst rock mass quality, i.e., the section with the highest basic quality grade of the surrounding rock, to ensure the reliability of stress monitoring.

[0083] In some examples, such as Figure 2 As shown, the aforementioned steps for determining the layout of multiple disturbance stress test boreholes based on the basic rock mass quality grade of the tunnel surrounding rock include:

[0084] Based on the stress monitoring section, the height line and span line of the tunnel 10 to be monitored are determined.

[0085] Obtain the height h and span l of the tunnel to be monitored;

[0086] A polar coordinate system is established with the intersection of the elevation line and the span line as the pole O, the ray originating from the pole O and passing through the vertex of the tunnel 10 to be monitored as the polar axis, and the clockwise direction as the positive direction.

[0087] When the basic quality grade of the surrounding rock of the tunnel is Grade I, Grade II or Grade III, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the form of the first borehole layout.

[0088] Among them, multiple disturbance stress test boreholes include a top test hole 100, a first side test hole 300, and a first shoulder test hole 200. The first hole layout is as follows:

[0089] Along the first preset angle direction, a top measuring hole 100 with a depth of 3h is opened on the surrounding rock of the tunnel. The first preset angle direction is greater than or equal to -10° and less than or equal to 10°.

[0090] Along the second preset angle direction, a first side measuring hole 300 with a hole depth of 4l is opened on the surrounding rock of the tunnel. The second preset angle direction is greater than or equal to 85° and less than or equal to 95°.

[0091] Along the third preset angle direction, a first shoulder measuring hole 200 with a depth of 1.5(l+h) is opened on the surrounding rock of the tunnel. The third preset angle direction is greater than or equal to -45° and less than or equal to -30°.

[0092] like Figure 2 As shown, with the stress monitoring section selected, the height line and span line of the tunnel 10 to be monitored can be determined based on the stress monitoring section.

[0093] It is understandable that the stress monitoring section includes the cross-section of the tunnel 10 to be monitored, and the height and span directions of the tunnel 10 to be monitored can be determined based on the cross-section of the tunnel 10, such as... Figure 2 As shown, taking the cross-section of the tunnel 10 to be monitored as an arch as an example, the height line of the tunnel 10 to be monitored is a straight line perpendicular to the bottom of the tunnel 10 to be monitored and passing through the top of the cross-section, and the span line of the tunnel 10 to be monitored is a straight line perpendicular to the height line of the tunnel 10 to be monitored and passing through the geometric center of the cross-section.

[0094] Simultaneously, the height h and span l of the tunnel to be monitored are obtained. The height h and span l of the tunnel to be monitored can be obtained from the tunnel plan or other design data of the tunnel 10 to be monitored, so as to provide a reference for the arrangement depth of each disturbance stress test borehole. It can be understood that the arrangement depth is the borehole depth. Then, the intersection of the height line and the span line is taken as the pole O, the ray starting from the pole O and passing through the vertex of the tunnel 10 to be monitored is taken as the polar axis, and the clockwise direction is taken as the positive direction, so as to provide a reference for the arrangement position of multiple disturbance stress test boreholes according to the aforementioned polar coordinate system.

[0095] If the basic quality grade of the surrounding rock of the tunnel is Grade I, II, or III, it indicates that the quality of the surrounding rock of the tunnel to be monitored, Tunnel 10, is relatively good, with high hardness and integrity. The stress field distribution of the surrounding rock on both sides of the tunnel can have a high degree of symmetry. Therefore, fewer disturbance stress test boreholes can be drilled on the surrounding rock of Tunnel 10 to ensure that the surrounding rock of multiple locations near Tunnel 10 can be monitored, while saving drilling costs and controlling the number of stress sensors used in the future.

[0096] Furthermore, when the basic quality grade of the surrounding rock of the tunnel is Grade I, Grade II, or Grade III, multiple disturbance stress test boreholes, including a top test hole 100, a first side test hole 300, and a first shoulder test hole 200, are arranged in the aforementioned first borehole layout to monitor the top surrounding rock, the shoulder surrounding rock on one side, and the side surrounding rock on the other side of the tunnel 10 to be monitored.

[0097] Understandably, when the basic quality grade of the surrounding rock mass of the tunnel is Grade I, II, or III, based on the first borehole layout, borehole monitoring was only conducted on one shoulder and the other side of the tunnel. The distribution information of the surrounding rock mass of the shoulder and side that was not monitored by borehole can be referenced from the stress information obtained based on the first shoulder borehole 200 and the stress information obtained based on the first side borehole 300, respectively. This allows the good quality of the surrounding rock mass of the tunnel to be utilized, saving the cost of arranging disturbance stress test boreholes.

[0098] In some feasible examples, the first preset angle direction is 0°, the second preset angle direction is 90°, and the third preset angle direction is -45°.

[0099] In some examples, the aforementioned steps of determining the layout of multiple disturbance stress test boreholes based on the basic quality grade of the surrounding rock mass of the tunnel, such as... Figure 3 As shown, it also includes:

[0100] When the basic quality grade of the surrounding rock of the tunnel is Class IV, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the first and second borehole layouts.

[0101] Among them, the multiple disturbance stress test boreholes also include a second side test hole 500 and a second shoulder test hole 400, and the second hole layout is as follows:

[0102] Along the fourth preset angle direction, a second shoulder measuring hole 400 with a depth of 1.5(l+h) is opened on the surrounding rock of the tunnel. The fourth preset angle is greater than or equal to 30° and less than or equal to 45°.

[0103] Along the fifth preset angle direction, a second side measuring hole 500 with a depth of 4l is opened on the surrounding rock of the tunnel. The fifth preset angle direction is greater than or equal to -95° and less than or equal to -85°.

[0104] Specifically, if the basic quality grade of the surrounding rock of the tunnel is Class IV, it indicates that the surrounding rock of the tunnel to be monitored, 10, is slightly weaker and has poor rock integrity, with some breakage. The symmetry of the stress field distribution on both sides of the tunnel is reduced. Therefore, it is necessary to arrange multiple disturbance stress test boreholes in a relatively symmetrical manner on both sides of the surrounding rock of the tunnel to be monitored, so as to avoid missing the monitoring of the surrounding rock that is prone to breakage in some areas.

[0105] Furthermore, such as Figure 3 As shown, when the basic quality grade of the surrounding rock of the tunnel is Class IV, multiple disturbance stress test boreholes include a top test borehole 100, a first side test borehole 300, a second side test borehole 500, a first shoulder test borehole 200, and a second shoulder test borehole 400. Among them, the top test borehole 100, the first side test borehole 300, and the first shoulder test borehole 200 are arranged in the aforementioned first borehole layout, and the second side test borehole 500 and the second shoulder test borehole 400 are arranged in the aforementioned second borehole layout, so as to monitor the top surrounding rock, the shoulder surrounding rock on both sides, and the side surrounding rock on both sides of the tunnel 10 to be monitored respectively. Moreover, the intervals between the aforementioned disturbance stress test boreholes are relatively uniform, which is conducive to improving the monitoring coverage.

[0106] In some feasible examples, the fourth preset angle is 45° and the fifth preset angle is -90°.

[0107] In some examples, the aforementioned steps of determining the layout of multiple disturbance stress test boreholes based on the basic quality grade of the surrounding rock mass of the tunnel, such as... Figure 4 As shown, it also includes:

[0108] When the basic quality grade of the surrounding rock of the tunnel is Grade V, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the first, second and third borehole layouts.

[0109] Among them, the multiple disturbance stress test boreholes also include a first bottom measuring hole 600 and a second bottom measuring hole 700, and the third hole layout is as follows:

[0110] Along the sixth preset angle direction, a first bottom measuring hole 600 with a depth of (l+h) is opened on the surrounding rock of the tunnel. The sixth preset angle direction is greater than or equal to 135° and less than or equal to 150°.

[0111] Along the seventh preset angle direction, a second bottom measuring hole 700 with a depth of (l+h) is opened on the surrounding rock of the tunnel. The seventh preset angle direction is greater than or equal to -150° and less than or equal to -135°.

[0112] Specifically, if the basic quality grade of the surrounding rock mass of the tunnel is V, it indicates that the quality of the surrounding rock of the tunnel 10 to be monitored is relatively poor, the hardness and integrity of the surrounding rock are extremely low, and the stress field distribution of the surrounding rock on both sides of the tunnel is likely to have large differences. Therefore, it is necessary to conduct more comprehensive monitoring of the surrounding rock around the tunnel 10 to avoid missing the monitoring of the surrounding rock that is prone to local fracturing.

[0113] Furthermore, such as Figure 4 As shown, when the basic quality grade of the surrounding rock of the tunnel is Grade V, multiple disturbance stress test boreholes include a top test hole 100, a first side test hole 300, a second side test hole 500, a first shoulder test hole 200, a second shoulder test hole 400, a first bottom test hole 600, and a second bottom test hole 700. Among them, the top test hole 100, the first side test hole 300, and the first shoulder test hole 200 are arranged in the aforementioned first hole arrangement, the second side test hole 500 and the second shoulder test hole 400 are arranged in the aforementioned second hole arrangement, and the first bottom test hole 600 and the second bottom test hole 700 are arranged in the third hole arrangement, so as to monitor the top surrounding rock, the shoulder surrounding rock on both sides, the side surrounding rock on both sides, and the bottom surrounding rock of the tunnel 10 to be monitored.

[0114] It should be noted that when the basic quality grade of the surrounding rock of the tunnel is Grade V, the bottom surrounding rock of the tunnel to be monitored, 10, may also be prone to breakage and instability, which could lead to poor tunnel passability and affect daily production. Therefore, the first bottom measuring hole 600 and the second bottom measuring hole 700 are arranged in the bottom surrounding rock of the tunnel to be monitored, according to the third hole arrangement method, and stress sensors are arranged in each bottom measuring hole. This allows for continuous monitoring of the stress condition of the bottom surrounding rock, which is beneficial for predicting the breakage and instability of the bottom surrounding rock, and thus provides a guarantee for the continuity of production.

[0115] In some feasible examples, the sixth preset angle direction is 150° and the seventh preset angle direction is -150°.

[0116] It is understood that the aforementioned 3h represents 3 times the height h of the tunnel to be monitored; the aforementioned 4l represents 4 times the span l of the tunnel to be monitored; the aforementioned 1.5(l+h) represents 1.5 times the sum of the height h and the span l of the tunnel to be monitored; and the aforementioned (l+h) represents the sum of the height h and the span l of the tunnel to be monitored. Accordingly, the depth of the top measuring hole is 3h, the depth of each shoulder measuring hole is 1.5(l+h), the depth of each side measuring hole is 4l, and the depth of each bottom measuring hole is (l+h). The unit of the aforementioned hole depths can be meters.

[0117] In some examples, such as Figures 5 to 8 As shown, the spacing of the stress sensors increases along the direction from the borehole opening to the bottom of each disturbance stress test borehole.

[0118] Specifically, after the aforementioned disturbance stress test boreholes are opened, multiple stress sensors are arranged at intervals along the borehole from the borehole opening to the bottom of the borehole, i.e., along the borehole depth. The intervals between the stress sensors are increased, resulting in a situation where the stress sensors are arranged more densely closer to the borehole opening and more sparsely closer to the bottom of the borehole. This enables high-density monitoring of key stress monitoring areas and low-density monitoring of areas with relatively low stress monitoring criticality, further saving the number of stress sensors used.

[0119] It should be noted that the increasing spacing of the stress sensors along the borehole from the opening to the bottom of each disturbance stress test borehole can be a continuous increase. For example, assuming a borehole depth of 5m is arranged within it, and the five stress sensors are numbered Sensor 1, Sensor 2, Sensor 3, Sensor 4, and Sensor 5 from the opening to the bottom, Sensor 1 is 0.2m from the opening, Sensor 1 is 0.5m from Sensor 2, Sensor 2 is 1m from Sensor 3, Sensor 3 is 1.5m from Sensor 4, and Sensor 4 is 1.6m from Sensor 5. It is understood that when the spacing increases continuously, the number and spacing of the stress sensors are not limited to the data given in this example.

[0120] Along the borehole from the opening to the bottom of each disturbance stress test borehole, the spacing of the stress sensors can increase in stages. For example, assuming a borehole depth of 10m is arranged with 7 stress sensors, numbered 6, 7, 8, 9, 10, 11, and 12 from the opening to the bottom, sensor 6 is 0.5m from the opening. Sensors 6, 7, and 8 are equidistant, with a 1m interval between them: sensor 7 and 6, sensor 8 and 7, sensor 9 and 8, and sensor 10 and 9. Sensors 11 and 10 are spaced 2m apart, and sensor 12 and 11 are also spaced 2m apart. It is understood that when using a staged increase in spacing, the number and spacing of the stress sensors are not limited to the data given in this example.

[0121] Understandably, during the excavation and support stages of the tunnel 10 to be monitored, the surrounding rock near the outline of the tunnel 10 will experience greater disturbance stress, and the changes in disturbance stress will be more drastic. Therefore, in order to more accurately grasp the stress on the surrounding rock near the outline of the tunnel 10 to be monitored, stress sensors are arranged at a higher density in the area near the borehole opening in each disturbance stress test borehole. Correspondingly, the surrounding rock far from the outline of the tunnel 10 to be monitored tends to experience less disturbance stress, and the changes in disturbance stress are relatively gentle. Therefore, stress sensors can be arranged at a lower density in the area near the bottom of the borehole in each disturbance stress test borehole to reduce the number of stress sensors used and lower monitoring costs.

[0122] In some feasible examples, such as Figures 5 to 8 As shown, the stress sensors in each disturbance stress test borehole can be arranged in the following sensor arrangement:

[0123] like Figure 5 As shown, stress sensors are installed at positions 0.1h, 0.2h, 0.3h, 0.6h, 1.0h, 1.4h, 2.0h, and 3.0h along the direction from the top of the measuring hole to the bottom, for a total of eight stress sensors. Figure 5 TS1 to TS8 represent the aforementioned eight stress sensors that are sequentially installed along the direction from the opening of the top measuring hole to the bottom of the hole. It can be understood that the stress sensor installation positions here are obtained with the opening of the top measuring hole as the 0 point position.

[0124] like Figure 6 As shown, stress sensors are installed at positions 0.1l, 0.2l, 0.3l, 0.6l, 1.0l, 1.4l, 2.0l, 3.0l, and 4.0l along the direction from the borehole opening to the bottom of each side test hole, for a total of 9 stress sensors. Figure 6 BS1 to BS9 represent the aforementioned nine stress sensors that are sequentially installed along the direction from the opening to the bottom of each side measuring hole. It can be understood that the stress sensor installation positions here are obtained with the opening of each side measuring hole as the 0 point position.

[0125] like Figure 7 As shown, along the direction from the opening to the bottom of each shoulder-shaped measuring hole, stress sensors are installed at positions of 0.05(l+h), 0.1(l+h), 0.15(l+h), 0.3(l+h), 0.5(l+h), 0.7(l+h), (l+h), and 1.5(l+h), for a total of eight stress sensors. Figure 6JS1 to JS8 represent the aforementioned eight stress sensors that are sequentially installed along the direction from the opening to the bottom of each shoulder measuring hole. It can be understood that the stress sensor positions here are obtained with the opening of each shoulder measuring hole as the 0 point position.

[0126] like Figure 8 As shown, stress sensors are installed at positions 0.05(l+h), 0.1(l+h), 0.15(l+h), 0.3(l+h), 0.5(l+h), 0.7(l+h), and (l+h) along the direction from the opening to the bottom of each bottom measuring hole, for a total of 7 stress sensors. Figure 8 DS1 to DS7 represent the aforementioned seven stress sensors that are sequentially installed along the direction from the opening to the bottom of each bottom measuring hole. It can be understood that the stress sensor positions here are obtained with the opening of each bottom measuring hole as the 0 point position.

[0127] In some examples, the method for testing the disturbance stress of the surrounding rock in tunnels also includes:

[0128] Obtain the monitoring time information of each stress sensor;

[0129] Based on stress monitoring information and monitoring time information, the primary relationship between surrounding rock stress and monitoring duration is determined.

[0130] Specifically, the monitoring time information of each stress sensor is further obtained. The monitoring time information corresponds to the monitoring stress information and is used to reflect the acquisition time of the monitoring stress information. Thus, based on the stress monitoring information and the monitoring time information, the primary relationship between the surrounding rock stress and the monitoring time can be determined. This facilitates the monitoring personnel to analyze and determine the change law of the surrounding rock stress over time based on the primary relationship, and provides a reliable prediction basis for predicting the fracture and instability time of the surrounding rock of the tunnel.

[0131] Understandably, the primary relationship can be determined by mapping forms such as empirical formulas, relationship curves, and relationship tables, based on the correspondence between stress monitoring information and monitoring time information. Furthermore, a set of primary relationships can be obtained based on the monitoring time information and the measured stress monitoring information of each stress sensor.

[0132] In some examples, the method for testing the disturbance stress of the surrounding rock in tunnels also includes:

[0133] Obtain the measurement point location information of each stress sensor;

[0134] Based on stress monitoring information and measuring point location information, a second relationship is determined between the surrounding rock stress and the borehole depth of the disturbance stress test borehole.

[0135] Specifically, the location information of each stress sensor's measuring point is further obtained. This measuring point location information corresponds to the monitored stress information. It can be understood that the measuring point refers to the stress monitoring point, which is also the location of the stress sensor. Since the stress sensor is arranged in the disturbance stress test borehole, the measuring point location information reflects the depth of the stress sensor in the corresponding disturbance stress test borehole. Therefore, based on the stress monitoring information and the measuring point location information, a second relationship can be determined between the surrounding rock stress on the tunnel surrounding rock and the depth of the disturbance stress test borehole. This facilitates the monitoring personnel to analyze and determine the variation law of surrounding rock stress with the depth of the borehole based on the second relationship, and provides a reliable prediction basis for predicting the fracture and instability location of the tunnel surrounding rock.

[0136] Understandably, the second relationship can be determined by empirical formulas, relationship curves, relationship tables, and other mapping forms summarized based on the correspondence between stress monitoring information and measurement point location information. Furthermore, a set of second relationships can be obtained based on the monitoring time information and measured stress monitoring information from multiple stress sensors within each disturbance stress test borehole.

[0137] In some examples, such as Figure 9 and Figure 10 As shown, the method for testing the disturbance stress of tunnel surrounding rock also includes:

[0138] Based on the stress monitoring information and monitoring time information of each stress sensor, the stress duration curve of each stress sensor is determined, and the stress duration curve is used to determine the first relationship;

[0139] Based on stress monitoring information and measurement point location information, stress-depth curves are established for each disturbance stress test borehole. These stress-depth curves are used to determine the second relationship.

[0140] like Figure 9 As shown, Figure 9The horizontal axis represents the monitoring duration in days; the vertical axis represents the surrounding rock stress in MPa. Specifically, stress-duration curves for each stress sensor can be established based on the stress monitoring information and monitoring time information of each stress sensor. The stress-duration curve corresponding to each stress sensor can reflect the change law of surrounding rock stress over time within the monitoring range of that stress sensor. Therefore, the aforementioned first relationship can be determined using the stress-duration curve. Furthermore, the stress-duration curve has high intuitiveness, facilitating monitoring personnel to predict the time of fracture and instability of tunnel surrounding rock and determine whether the tunnel surrounding rock is in a stable state, thus improving the efficiency of tunnel surrounding rock stability analysis. In addition, the nonlinear mechanical properties and time effects of the tunnel surrounding rock are considered during the testing process, accurately reflecting the spatiotemporal evolution of disturbance stress in the tunnel surrounding rock. Therefore, the tunnel surrounding rock disturbance stress testing method provided in this application is particularly suitable for the disturbance stress testing of weak and fractured surrounding rock in deeply buried tunnels.

[0141] like Figure 10 As shown, Figure 10 The horizontal axis represents the borehole depth in meters (m), and the vertical axis represents the surrounding rock stress in MPa (MPa). Based on stress monitoring and monitoring time information, stress-depth curves can be established for each disturbed stress test borehole. Each stress-depth curve reflects the change in surrounding rock stress over time within the monitoring range of multiple stress sensors in that borehole. This allows for the determination of the aforementioned second relationship. Furthermore, the stress-depth curve is highly intuitive, facilitating monitoring personnel in predicting the location of tunnel surrounding rock fracturing and instability, and determining whether the surrounding rock at various locations is in a stable state, thus improving the efficiency of tunnel surrounding rock stability analysis.

[0142] It is understandable that the stress-depth curve of each perturbation stress test borehole is obtained based on the stress monitoring information and measurement point location information of multiple stress sensors within the perturbation stress test borehole.

[0143] In some examples, such as Figure 9 and Figure 10 As shown, the method for testing the disturbance stress of tunnel surrounding rock also includes:

[0144] Based on the stress-hole depth curve, the critical stress point of the tunnel surrounding rock is determined. The critical stress point is the first peak point in the stress-hole depth curve along the direction of increasing hole depth.

[0145] Based on the critical stress point, the damage and fracture zone and the elastic zone of the tunnel surrounding rock are determined.

[0146] Based on the stress-duration curve, the self-stabilization duration of the surrounding rock and the support stabilization duration of the surrounding rock are determined.

[0147] like Figure 10 As shown, specifically, the critical stress point of the tunnel surrounding rock can be determined based on the stress-hole depth curve. The critical stress point is the first peak point along the direction of increasing hole depth in the stress-hole depth curve. It can be understood that if there are multiple peak points in the stress-hole depth curve, the critical stress point is the peak point with the smallest hole depth. Therefore, the critical stress point is the peak point closest to the outline of the tunnel to be monitored among the multiple peak points. The hole depth position corresponding to the critical peak point is defined as the critical position A1. The critical position A1 can be used to divide the tunnel surrounding rock into the elastic zone and the damage and fracture zone. The tunnel surrounding rock area with a hole depth less than the critical position A1 is the damage and fracture zone. Part of the tunnel surrounding rock in the damage and fracture zone is prone to large disturbance stress, thus easily leading to breakage and instability. The tunnel surrounding rock area with a hole depth greater than the critical position A1 is the elastic zone. Part of the tunnel surrounding rock in the elastic zone experiences relatively small stress, thus having better stability. This provides a reference for determining the location for preventing instability of the tunnel surrounding rock.

[0148] For example, if in the region where the hole depth in the stress-hole depth curve is greater than the critical position, as shown in the example... Figure 10 The stress fluctuation area of ​​the surrounding rock enclosed in interval A2 can be used to determine that the tunnel surrounding rock zone corresponding to interval A2 is a fracture zone. The borehole depth position corresponding to the peak in interval A2 is the starting point of the fracture in the surrounding rock zone, and the borehole depth position corresponding to the trough in interval A2 is the ending point of the fracture in the surrounding rock zone. That is, within the stress fluctuation area where the borehole depth position in the stress-borehole depth curve is greater than the critical position, the area between an adjacent set of peak and trough borehole depth positions is the surrounding rock fracture zone. Similarly, through... Figure 10 Interval A3 in the diagram can also be used to determine a fracture zone of the surrounding rock.

[0149] like Figure 10 The stress in the surrounding rock within region A4 of the middle section changes very little with the borehole depth. Therefore, the surrounding rock zone corresponding to region A4 can be identified as a stable zone. The surrounding rock of some tunnels within the stable zone has good stability and the possibility of fracturing and instability is low. By obtaining the actual slope of the stress-hole depth curve and setting a stable reference slope, the borehole depth range where the actual slope is less than the stable reference slope can be identified as a stable zone.

[0150] It should be noted that, Figure 10 The diagram shows three stress location curves. This is because the stress sensor used in the actual application is a three-dimensional stress sensor, which obtains stress location curves in three directions within the same disturbance stress test borehole. From top to bottom, the three stress location curves are the stress location curve in the direction of self-weight stress, the stress location curve in the direction of tunnel span, and the stress location curve in the direction of tunnel axis. The direction of self-weight stress is also the direction of gravity.

[0151] Simultaneously, the self-stabilization time of the surrounding rock and the support stabilization time of the tunnel can be determined based on the stress-duration curve. The self-stabilization time of the surrounding rock represents the time required for the stress of the surrounding rock to stabilize on its own from the start of excavation. It can reflect the overall rheological properties of the surrounding rock and can provide reference data for subsequent prediction of tunnel surrounding rock fracturing and instability. The support stabilization time represents the time required for the surrounding rock to stabilize from the start of support operations. It reflects the coupling process between support and surrounding rock and can provide further reference for subsequent prediction of tunnel surrounding rock fracturing and instability.

[0152] The steps for determining the self-stabilization time of the surrounding rock and the support stabilization time of the tunnel based on the stress-time curve may include:

[0153] Obtain the excavation time of the tunnel to be monitored;

[0154] According to the stress duration curve, the first monitoring moment when the slope of the stress duration curve first falls below the self-stabilizing reference slope after the excavation time is obtained.

[0155] The difference between the first monitoring time and the excavation time is determined as the self-stabilization time of the surrounding rock;

[0156] Obtain the start time of support for the tunnel to be monitored;

[0157] According to the stress duration curve, after obtaining the support initiation time, the second monitoring time is when the slope of the stress duration curve is first lower than the support stability reference slope.

[0158] The difference between the second monitoring time and the support start time is determined as the support stabilization time.

[0159] The excavation time and the support start time can be obtained from the construction records of the tunnel to be monitored. The self-stabilizing reference slope and the support stability reference slope can be set in combination with the stability requirements of the surrounding rock of the tunnel, which can be 0.1 MPa / day or 0.1 MPa / week.

[0160] For example, Figure 9The diagram shows the stress-duration curve of the monitored tunnel from the time of excavation to the time it was put into operation. It can be understood that the excavation of the tunnel caused stress disturbance to the surrounding rock, resulting in a sustained and rapid increase in stress from time 0. When the monitoring time reaches the time corresponding to the dashed line T1, the slope of the surrounding rock stress curve decreases to 0.1 MPa / day, indicating that the rate of increase in surrounding rock stress with monitoring time tends to level off. If 0.1 MPa / day is taken as the self-stabilizing reference slope, then the time corresponding to the dashed line T1 is the first monitoring time. Since time 0 is the excavation time, the value at the time corresponding to the dashed line T1 is the self-stabilizing time of the surrounding rock. The time corresponding to the left boundary of interval T2 is the support start time. After the right boundary of interval T2 is the support start time, the slope of the stress-duration curve first falls below the support stabilization reference slope at the second monitoring time. Therefore, the difference between the time corresponding to the left boundary and the time corresponding to the right boundary of interval T2 is the support stabilization time.

[0161] Furthermore, after the second monitoring time, the surrounding rock of the tunnel maintained a stable stress state for a period of time. When the time reached the left boundary of interval T3, the stress of the surrounding rock underwent a sudden change. It can be determined that at the time corresponding to the left boundary of interval T3, the surrounding rock of the tunnel was again affected by other factors, resulting in stress disturbance. These other factors may be engineering disturbances such as tunnel excavation operations in the vicinity of the monitored tunnel. The self-stabilizing reference slope is used as a reference. Figure 9 The stress-duration curve shown in the figure shows that after the time corresponding to the left boundary of interval T3, the slope is again lower than the self-stabilizing reference slope at the time corresponding to the right boundary of interval T3. This indicates that the tunnel surrounding rock can recover stability under external disturbance. Correspondingly, if the slope of the stress disturbance curve remains greater than or equal to the self-stabilizing reference slope for a period of time exceeding the warning standby time from the time corresponding to the left boundary of interval T3, it indicates that the tunnel surrounding rock cannot achieve stability and that an instability accident is about to occur. The sum of the time corresponding to the left boundary of interval T3 and the warning standby time is determined as the warning time, thereby realizing real-time warning of tunnel surrounding rock instability.

[0162] In this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0163] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0164] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0165] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for testing the disturbance stress of surrounding rock in tunnels, characterized in that, include: Obtain the basic quality grade of the surrounding rock mass of the tunnel to be monitored; Based on the basic quality grade of the surrounding rock of the tunnel, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel. Multiple stress sensors are arranged at intervals in each of the aforementioned disturbance stress test boreholes; Obtain stress monitoring information from each of the stress sensors; The step of drilling multiple disturbance stress test boreholes in the surrounding rock of the tunnel according to the basic quality grade of the surrounding rock includes: A stress monitoring section is selected, and the stress monitoring section is perpendicular to the axial direction of the tunnel; Based on the basic quality grade of the surrounding rock of the tunnel, the hole layout of the multiple disturbance stress test boreholes is determined; According to the hole layout and the stress monitoring section, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel, wherein the axes of the multiple disturbance stress test boreholes are all located within the stress monitoring section; The step of determining the layout of the multiple disturbance stress test boreholes based on the basic quality grade of the surrounding rock of the tunnel includes: Based on the stress monitoring section, the height line and span line of the tunnel to be monitored are determined. Obtain the height h and span l of the tunnel to be monitored; A polar coordinate system is established with the intersection of the elevation line and the span line as the pole, the ray originating from the pole and passing through the vertex of the tunnel to be monitored as the polar axis, and the clockwise direction as the positive direction. When the basic quality grade of the surrounding rock of the tunnel is Grade I, Grade II or Grade III, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the form of the first borehole layout. The plurality of disturbance stress test boreholes include top test holes, first side test holes, and first shoulder test holes, wherein the first hole layout is as follows: Along a first preset angle direction, a top measuring hole with a depth of 3h is opened on the surrounding rock of the tunnel, wherein the first preset angle direction is greater than or equal to -10° and less than or equal to 10°; Along the second preset angle direction, a first side measuring hole with a depth of 4l is opened on the surrounding rock of the tunnel, the second preset angle direction being greater than or equal to 85° and less than or equal to 95°; Along a third preset angle direction, a first shoulder measuring hole with a depth of 1.5(l+h) is opened on the surrounding rock of the tunnel. The third preset angle direction is greater than or equal to -45° and less than or equal to -30°.

2. The method for testing the disturbance stress of surrounding rock in tunnels according to claim 1, characterized in that, The step of determining the layout of the plurality of disturbance stress test boreholes based on the basic quality grade of the surrounding rock of the tunnel further includes: When the basic quality grade of the surrounding rock of the tunnel is Grade IV, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the first and second borehole layouts. Among them, the plurality of disturbance stress test boreholes also include second side test holes and second shoulder test holes, and the second hole layout is as follows: Along the fourth preset angle direction, a second shoulder measuring hole with a depth of 1.5(l+h) is opened on the surrounding rock of the tunnel, wherein the fourth preset angle is greater than or equal to 30° and less than or equal to 45°; Along the fifth preset angle direction, a second side measuring hole with a depth of 4l is opened on the surrounding rock of the tunnel. The fifth preset angle direction is greater than or equal to -95° and less than or equal to -85°.

3. The method for testing the disturbance stress of tunnel surrounding rock according to claim 2, characterized in that, The step of determining the layout of the plurality of disturbance stress test boreholes based on the basic quality grade of the surrounding rock of the tunnel further includes: When the basic quality grade of the surrounding rock of the tunnel is Grade V, multiple disturbance stress test boreholes are opened on the surrounding rock of the tunnel in the first, second and third borehole layouts. The plurality of disturbance stress test boreholes further include a first bottom test hole and a second bottom test hole, and the third hole layout is as follows: Along the sixth preset angle direction, a first bottom measuring hole with a depth of (l+h) is opened on the surrounding rock of the tunnel, wherein the sixth preset angle direction is greater than or equal to 135° and less than or equal to 150°. Along the seventh preset angle direction, a second bottom measuring hole with a depth of (l+h) is opened on the surrounding rock of the tunnel. The seventh preset angle direction is greater than or equal to -150° and less than or equal to -135°.

4. The method for testing the disturbance stress of tunnel surrounding rock according to claim 3, characterized in that, The spacing between the stress sensors increases along the direction from the borehole opening to the bottom of each of the disturbance stress test boreholes.

5. The method for testing the disturbance stress of surrounding rock in tunnels according to any one of claims 1 to 4, characterized in that, Also includes: Obtain the monitoring time information of each of the stress sensors; Based on the stress monitoring information and the monitoring time information, a first relationship between the surrounding rock stress and the monitoring duration is determined.

6. The method for testing the disturbance stress of tunnel surrounding rock according to claim 5, characterized in that, Also includes: Obtain the measurement point location information of each stress sensor; Based on the stress monitoring information and the measuring point location information, a second relationship is determined between the surrounding rock stress and the hole depth of the disturbance stress test borehole.

7. The method for testing the disturbance stress of surrounding rock in tunnels according to claim 6, characterized in that, Also includes: Based on the stress monitoring information and monitoring time information of each stress sensor, a stress duration curve for each stress sensor is determined, and the stress duration curve is used to determine the first relationship; Based on the stress monitoring information and the measurement point location information, stress-depth curves are established for each of the disturbance stress test boreholes, and the stress-depth curves are used to determine the second relationship.

8. The method for testing the disturbance stress of tunnel surrounding rock according to claim 7, characterized in that, Also includes: Based on the stress-hole depth curve, the critical stress point of the tunnel surrounding rock is determined. The critical stress point is the first peak point in the stress-hole depth curve along the direction of increasing hole depth. Based on the critical stress point, the damage and fracture zone and the elastic zone of the tunnel surrounding rock are determined. Based on the stress-duration curve, the self-stabilization duration of the surrounding rock and the support stabilization duration of the surrounding rock are determined.

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