Comparison monitoring method for internal displacement of hard rock

Abstract

The invention discloses a hard rock internal displacement comparison monitoring method, and relates to the field of high-level radioactive waste dispose.The method comprises the steps that firstly, a hole is drilled in the direction from an excavated roadway to a TBM / drilling and blasting roadway to be excavated, and a TBM section / drilling and blasting section hard rock displacement monitoring system is arranged in the drilled hole; in the TBM method / drilling and blasting method excavation process, a TBM section / drilling and blasting section hard rock displacement monitoring system is adopted to obtain TBM section / drilling and blasting section displacement monitoring data, the hard rock displacement evolution law of a TBM roadway / drilling and blasting roadway is analyzed according to the TBM section / drilling and blasting section displacement monitoring data, and the accuracy of hard rock displacement response characterization in the TBM method and drilling and blasting method excavation process can be improved; the excavation process of the TBM method and the drilling and blasting method is guided according to the hard rock displacement evolution law analysis result of the TBM roadway and the drilling and blasting roadway, and the scientific construction process of the TBM method and the drilling and blasting method can be achieved.

Description

Technical Field

[0001] The present application relates to the technical field of high-level radioactive waste disposal, and in particular to a hard rock internal displacement comparison monitoring method. Background Art

[0002] High-level radioactive waste (abbreviated as HLW) is characterized by strong radioactivity, high toxicity and long half-life, making it extremely difficult to dispose of it safely and facing a series of scientific, technological and engineering challenges. Whether high-level radioactive waste can be safely disposed of is a strategic issue related to the sustainable development of the nuclear industry and environmental protection. The geological disposal repository for high-level radioactive waste has the characteristics of complex construction conditions, high safety level and long service life (tens of thousands of years), which makes research and development very difficult. To this end, based on previous research experience, it is necessary to first build an underground laboratory for high-level radioactive waste disposal at the depth of the repository, conduct site characteristic evaluation, and conduct on-site testing and verification of disposal technology, so as to provide the necessary scientific research foundation and practical experience for the construction of the repository.

[0003] TBM (Tunnel Boring Machine) and drilling and blasting are two commonly used methods in the construction of underground projects (underground laboratories and disposal repositories). They have their own characteristics and are suitable for different geological conditions and engineering requirements. In the excavation process of underground laboratories and disposal repositories, TBM and drilling and blasting are often used in combination. However, there is a lack of comparative analysis methods for the hard rock displacement response of the excavation process of the two methods in this field, which makes it difficult to guide the actual excavation process of TBM and drilling and blasting. Summary of the invention

[0004] The purpose of this application is to provide a hard rock internal displacement comparison monitoring method to accurately characterize the hard rock displacement response during TBM and drilling and blasting excavation, and to guide the scientific excavation of TBM and drilling and blasting.

[0005] To achieve the above objectives, this application provides the following solutions.

[0006] The present application provides a hard rock internal displacement comparison monitoring method, comprising:

[0007] Drill holes from the excavated tunnel toward the TBM tunnel to be excavated, and install the TBM section hard rock displacement monitoring system in the holes;

[0008] During the TBM excavation process, the TBM segment hard rock displacement monitoring system is used to obtain TBM segment displacement monitoring data;

[0009] Analyze the evolution law of hard rock displacement in TBM tunnels based on TBM segment displacement monitoring data;

[0010] Drill holes from the excavated tunnel to the direction of the drilling and blasting tunnel to be excavated, and install a hard rock displacement monitoring system for the drilling and blasting section in the boreholes;

[0011] During the drilling and blasting excavation process, the drilling and blasting section hard rock displacement monitoring system is used to obtain the drilling and blasting section displacement monitoring data;

[0012] Analyze the evolution law of hard rock displacement in the drilling and blasting tunnel based on the displacement monitoring data of the drilling and blasting section;

[0013] The analysis results of the hard rock displacement evolution law of TBM tunnels and drill and blast tunnels are used to guide the TBM and drill and blast excavation processes.

[0014] Optionally, drilling a hole from the excavated tunnel toward the TBM tunnel to be excavated and arranging a TBM section hard rock displacement monitoring system in the drill hole specifically includes:

[0015] Drill holes from the excavated tunnel toward the TBM tunnel to be excavated. The drilling directions include up-inclined, nearly horizontal, and down-inclined.

[0016] One or more of a multi-point displacement meter, a fiber grating FRP smart reinforcement and a sliding micrometer are buried at preset positions in corresponding boreholes to form a TBM section hard rock displacement monitoring system.

[0017] Optionally, embedding one or more of a multi-point displacement meter, a fiber Bragg grating (FRP) smart rib and a sliding micrometer at a preset position in the corresponding borehole specifically includes:

[0018] The distance between the sensor closest to the TBM tunnel sidewall in each borehole and the TBM tunnel sidewall is 0.1m-1m;

[0019] The sensor located on the central axis of the TBM tunnel is 0.1-1m away from the TBM tunnel wall.

[0020] Optionally, analyzing the hard rock displacement evolution law of the TBM tunnel according to the TBM segment displacement monitoring data specifically includes:

[0021] According to the TBM segment displacement monitoring data, the hard rock displacement of the TBM tunnel is divided into three stages: the slow growth stage of hard rock deformation before reaching the monitoring borehole, the rapid growth stage of deformation near the monitoring section, and the stable stage of hard rock deformation behind the monitoring section.

[0022] Optionally, analyzing the hard rock displacement evolution law of the TBM tunnel according to the TBM segment displacement monitoring data further includes:

[0023] Using piecewise function To fit the relationship between the displacement D(t) of the multi-point displacement meter and the distance S(t) between the face and the borehole axis during TBM tunnel excavation; where t represents time; t0, t1, t2, ... t N+1are the time nodes of each stage; D0, D1, D2, ..., D n are the displacement values ​​at the beginning of each stage; k1, k2, k3, ..., k n+1 are the displacement change rates in each stage respectively.

[0024] Optionally, the distance S(t) between the tunnel face and the borehole axis is given by the formula: Or S(t)=Kt+B for fitting; wherein K represents the slope of the S(t) curve, B represents the intercept; w represents the time factor, a represents the time factor coefficient, and b represents the exponential adjustment factor.

[0025] Optionally, drilling a hole from the excavated tunnel toward the drilling and blasting tunnel to be excavated, and arranging a drilling and blasting section hard rock displacement monitoring system in the hole specifically includes:

[0026] Drill holes from the excavated tunnel in a direction perpendicular to the excavation direction of the tunnel to be excavated. The drilling directions include upward, nearly horizontal, and downward.

[0027] One or more of a multi-point displacement meter, a fiber grating FRP smart rib and a sliding micrometer are buried at preset positions in corresponding boreholes to form a hard rock displacement monitoring system for the drilling and blasting section.

[0028] Optionally, one or more of a multi-point displacement meter, a fiber Bragg grating (FRP) smart rib and a sliding micrometer are buried at a preset position in the corresponding borehole, specifically including:

[0029] The distance between the sensor closest to the side wall of the drilling and blasting tunnel in each borehole and the side wall of the drilling and blasting tunnel is 0.3m-1m;

[0030] The sensor located on the central axis of the drilling and blasting tunnel is 0.3-1m away from the wall of the drilling and blasting tunnel.

[0031] Optionally, analyzing the hard rock displacement evolution law of the drilling and blasting tunnel according to the drilling and blasting section displacement monitoring data specifically includes:

[0032] According to the analysis of the displacement monitoring data of the drilling and blasting section, the displacement showed a step increase after each round of excavation in the drilling and blasting tunnel, and then the displacement growth decayed exponentially.

[0033] Optionally, analyzing the hard rock displacement evolution law of the drilling and blasting tunnel according to the drilling and blasting section displacement monitoring data specifically includes:

[0034] Using piecewise function To fit the curve of the displacement u(t) of the multi-point displacement meter over time T during the drilling and blasting tunnel excavation process; where T0, T1, T2, ... T N+1 are the time nodes of each stage; u0,u1,u2,...u Nare the displacement values ​​at the beginning of each stage; K1, K2, K3, ... K N+1 are the displacement change influence coefficients of each stage; α1, α2, α3, ... α N+1 are the time influence coefficients of each stage; β1, β2, β3, ... β N+1 are the time adjustment factors for each stage respectively.

[0035] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0036] The present application provides a hard rock internal displacement comparison monitoring method, which can accurately characterize the internal damage evolution process of hard rock by deploying a hard rock displacement monitoring system in the TBM section and the drilling and blasting section, and analyzing the hard rock displacement evolution law based on the displacement monitoring data obtained during the TBM / drilling and blasting excavation process. Furthermore, guiding the TBM and drilling and blasting excavation process based on the hard rock displacement evolution law analysis results of the TBM tunnel and the drilling and blasting tunnel can not only improve the safety of the project, optimize the construction plan, and improve the construction efficiency, but also realize scientific and intelligent management, providing important guarantees for the smooth implementation of underground projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 A schematic diagram of a flow chart of a hard rock internal displacement comparison monitoring method for this application;

[0039] Figure 2 Schematic diagram of drilling and sensor layout in TBM section and drilling and blasting section;

[0040] Figure 3 Schematic diagram of the structure of the multi-point displacement meter used for displacement monitoring;

[0041] Figure 4 Schematic diagram of the fiber Bragg grating (FRP) smart reinforcement structure used for displacement monitoring;

[0042] Figure 5 This is a schematic diagram of the displacement monitoring data of the horizontal borehole ZKB05 and the buried multi-point displacement meter;

[0043] Figure 6 This is a schematic diagram of the displacement monitoring data of the down-dip borehole ZKB04 and the buried multi-point displacement meter;

[0044] Figure 7 This is a schematic diagram of displacement monitoring data of a grating fiber FRP smart reinforcement in units of days;

[0045] Figure 8 This is a schematic diagram of displacement monitoring data of a grating fiber FRP smart reinforcement in hours;

[0046] Fig. 9 The diagram is a curve showing the change of the monitored displacement with the distance from the TBM wall;

[0047] Fig.10 This is a schematic diagram of the displacement monitoring data of a measuring point of a multi-point displacement meter in the drilling and blasting section. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0049] The purpose of this application is to provide a hard rock internal displacement comparison monitoring method to accurately characterize the hard rock displacement response during TBM and drilling and blasting excavation, and to guide the scientific excavation of TBM and drilling and blasting.

[0050] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0051] See also Figure 1 The present application provides a hard rock internal displacement comparison monitoring method, including the following steps 1 to 7. The present application method is mainly used in the excavation process of underground laboratories. In the embodiment of the present application, the rock mass condition in the excavation area is high integrity and high strength granite; of course, the present application method can also be applied to other hard rock areas.

[0052] Step 1: Drill holes from the excavated tunnel toward the TBM tunnel to be excavated, and deploy the TBM section hard rock displacement monitoring system in the boreholes.

[0053] like Figure 2 As shown in the left half, holes are drilled from the excavated tunnel to the TBM tunnel (also called tunnel) to be excavated. The holes (represented by straight lines in the figure) include three directions: up-dipping, nearly horizontal, and down-dipping. Multi-point displacement meters, fiber Bragg grating FRP smart bars or sliding micrometers are buried at preset positions in the corresponding holes to form a TBM section hard rock displacement monitoring system. Figure 2As shown in the left half, the sensor (measurement point) located on the central axis of the TBM tunnel is 0.1-1m away from the TBM tunnel wall. And the distance between the sensor (measurement point) closest to the TBM tunnel side wall in each borehole and the TBM tunnel side wall is set to 0.3m-1m, which can ensure that the sensor is arranged as close as possible to the maximum stress point obtained by numerical simulation and avoid damage by excavation.

[0054] Among them, the multi-point displacement meter structure is as follows Figure 3 As shown, it includes a measuring point fixing head 301, a solid displacement transmission rod 302, a blocking limit sleeve 303, a sleeve-type rigid displacement transmission rod 304, a low-friction material 305, a sleeve probe 306 and a measuring tool 307. The sleeve probe 306 is located in the hard rock wall 308 of the tunnel and has a measuring plane and a measuring hole 309. In the embodiment of the present application, the multi-point displacement meter model specification is BGK-4450, with a range of 0 to 12.5 mm, a sensitivity of 0.025 mm / F, a measurement accuracy of ±0.1% F·S, a temperature measurement range of -25 to 60°C, a temperature measurement accuracy of ±0.5°C, and a water seepage prevention pressure of ≥1.0 MPa.

[0055] Fiber Bragg Grating FRP Intelligent Reinforcement Structure Figure 4 As shown, it includes FRP tendons 401, fiber Bragg gratings 402, anchor heads 403, displacement isolation layers 404, grouting 405, and optical cables 406. The fiber Bragg grating 402 can be further divided into a fiber Bragg grating temperature sensor 407 and a fiber Bragg grating strain sensor 408. The fiber Bragg grating FRP smart tendon selected in the embodiment of the present application has a measuring range of 2 to 4 mm, a displacement resolution of 0.005 mm, a grating center wavelength of 1525 to 1565 nm, an operating temperature of -30°C to 80°C, and 18 measuring points. In the drilling, the top measuring point is 0.5 m away from the wall, the spacing between measuring points 1 to 4 is 0.1 m, the spacing between measuring points 5 to 8 is 0.3 m, the spacing between measuring points 9 to 12 is 0.5 m, and the spacing between measuring points 13 to 18 is 1 m.

[0056] The layout of the sliding micrometer needs to ensure that the measuring line is arranged along the center line of the tunnel or the key position that needs to be monitored. The probe uses the ball-cone positioning principle to measure the mark on the measuring tube, which can ensure the accuracy and stability of the measurement. During the layout process, the sliding micrometer measures the displacement along the measuring line by the line method. This method is different from the traditional point method monitoring principle. It can continuously measure the information between two adjacent points, thereby deriving the axial and lateral deformation distribution on the entire measuring line. In order to ensure the accuracy of the measurement, the sliding micrometer needs to be calibrated regularly before and after each measurement to ensure very high measurement accuracy and long-term stability.

[0057] exist Figure 2In the illustrated embodiment, some boreholes and sensor layout positions of the TBM section hard rock displacement monitoring system are shown in Table 1. In Table 1, ZKB is a multi-point displacement meter borehole, and the multi-point displacement meter is numbered with the letter D; ZKF is a sliding micrometer borehole, and the sliding micrometer is numbered with the letter H; ZKA is a fiber Bragg grating FRP smart tendon borehole, and the fiber Bragg grating FRP smart tendon is numbered with the letter F.

[0058] Table 1 Some boreholes and sensor layout locations of the hard rock displacement monitoring system of the TBM section

[0059]

[0060]

[0061] Step 2: During TBM excavation, the TBM segment hard rock displacement monitoring system is used to obtain TBM segment displacement monitoring data.

[0062] During the TBM excavation process, the multi-point displacement meter, fiber Bragg grating FRP intelligent reinforcement and sliding micrometer deployed in the TBM section are used to monitor the displacement data at different positions and times, and the displacement change curve over time is plotted. The displacement monitoring data of the horizontal borehole ZKB05 and the buried multi-point displacement meter are shown in the figure. Figure 5 The mileage is 3346.10m. The displacement monitoring data of the down-dip borehole ZKB04 and the buried multi-point displacement meter are as follows Figure 6 The mileage is 3346.80m. The monitoring results of a grating fiber FRP smart reinforcement are as follows Figure 7 As shown, the displacement variation curve over time is shown in days, with the maximum displacement being approximately 1.1 mm and 0.11 m away from the TBM sidewall. Figure 8 The displacement versus time curve is shown in hours.

[0063] Step 3: Analyze the hard rock displacement evolution law of the TBM tunnel based on the TBM segment displacement monitoring data.

[0064] like Figures 5 to 8 As shown in the figure, the black curve represents the change curve of the distance S between the face and the borehole axis over time, which reflects the excavation process of the TBM to a certain extent. The slope of the curve represents the excavation rate. When the slope is zero, the TBM stops excavating. It can be observed that the displacement of the measuring point increases in a step-like manner with the excavation of the TBM, and the displacement change of the measuring point is consistent with the change of the curve S. In some embodiments, the following piecewise function can be used to describe the relationship between the displacement D(t) of the measuring point of the multi-point displacement meter and the distance S(t) between the face and the borehole axis during the TBM tunnel excavation process:

[0065]

[0066] Where D(t) represents the displacement of the measuring point at time t, which represents the displacement value measured by the multi-point displacement meter of the TBM section. S(t) is the distance between the tunnel face and the borehole axis at time t, which represents the relative position of the tunnel face relative to the borehole during the TBM excavation process. D0, D1, D2, ..., D n are the displacement values ​​at the beginning of each stage, representing the initial displacement point in each time period, and n is a positive integer. k1, k2, k3, ..., k n+1 are the displacement change rates of each stage, indicating the influence of the distance change between the tunnel face and the borehole axis on the displacement in each time period. This parameter can be obtained by fitting the monitoring data. N+1 is the time node of each stage, representing the start time of different stages in the TBM excavation process. This formula assumes that in each stage, there is a linear relationship between the displacement D(t) of the measuring point and the distance S(t) between the face and the borehole axis. This assumption is applicable to the direct relationship between displacement and distance during TBM excavation. The use of piecewise function (1) to describe the change of D(t) is suitable for the sudden change characteristics of displacement during TBM excavation. The rate of change in each stage may be different, reflecting the displacement response under different excavation speeds or hard rock conditions. The initial displacement D of each stage is i (i=0,1,2,...,n) represents the baseline displacement at the beginning of the stage, and the subsequent displacement changes are based on this baseline. i The values ​​of (i=1,2,...,n+1) provide an understanding of the displacement response at each stage. i The value means that the change in the distance between the tunnel face and the borehole axis has a greater impact on the displacement at this stage. i (i=0,1,2,...,n+1) can be determined through displacement monitoring data, usually at the moment when a significant change occurs during the excavation of the TBM. Through this piecewise linear model, the displacement changes measured by multi-point displacement meters during the TBM excavation process can be effectively described and predicted, helping engineers to conduct real-time monitoring and risk assessment.

[0067] Among them, the distance S(t) between the tunnel face and the borehole axis at different times t can be fitted using the following formula (2) or (3):

[0068]

[0069] S(t)=Kt+B (3)

[0070] Where K represents the slope of the S(t) curve, B is the intercept, w represents the time factor, a is the factor coefficient, and b is the exponential adjustment factor.

[0071] By analyzing Figures 5 to 8 The displacement monitoring data of the TBM section shown in the figure can be used to obtain the evolution law of the hard rock displacement of the TBM tunnel. The hard rock displacement at different depths can be divided into the following three stages:

[0072] 1) Slow growth stage of hard rock deformation before reaching the monitoring borehole: Before the excavation face reaches the monitoring borehole, the displacement of the measuring point does not change much. Before the tunnel face reaches the axis of the monitoring borehole, hard rock deformation begins to occur;

[0073] 2) Rapid deformation growth stage near the monitoring section: When the tunnel face reaches the vicinity of the monitoring borehole axis, the internal displacement of the hard rock increases rapidly;

[0074] 3) Stable deformation stage of hard rock behind the monitoring section: After the face excavation passes the monitoring borehole, the internal displacement of the hard rock begins to slow down. When the face excavation advances to a certain distance from the monitoring borehole (this distance is positively correlated with the excavation diameter), the influence of excavation unloading decreases, and the hard rock deformation rate tends to be stable. For example, when the excavation diameter is 7m, the face excavation advances to about 10m from the monitoring borehole, the influence of excavation unloading decreases, and the hard rock deformation rate tends to be stable.

[0075] From the above analysis, it can be seen that tunnel excavation is accompanied by hard rock deformation and stress adjustment process. Hard rock deformation is dynamic, and the displacement change curve of deep measuring points shows the characteristics of slow growth-rapid rise-trend to stability. This is because the rock mass of the measuring section has not been excavated before the excavation face reaches the monitoring borehole. Under its support, the displacement and displacement rate of the measuring point are very small; after the face passes the monitoring borehole, the support of the face gradually weakens, and the displacement increases rapidly in a short time; after the excavation face is pushed over a certain distance, with the release of hard rock deformation and the gradual reduction of the face constraint, the hard rock displacement rate gradually decreases and tends to be stable in deformation.

[0076] Furthermore, the monitoring results of each multi-point displacement meter were analyzed to obtain the displacement curve with the distance from the TBM wall, as shown in Fig. 9 As shown in , it characterizes the temporal and spatial characteristics of hard rocks at different depths and can be fitted using a piecewise linear function. Fig. 9 The monitoring results shown can be analyzed to derive the following evolution law of hard rock displacement in the TBM tunnel: (1) The displacement of hard rock at measuring points in different areas and at different depths is quite different; (2) The closer the measuring points are to the TBM excavation surface, the greater the displacement of the hard rock after stabilization, and it gradually decreases along the radial direction of the tunnel; (3) After stabilization, the displacement of each measuring point decreases nonlinearly along the radial direction of the tunnel, with a faster displacement reduction rate close to the excavation surface and a slower displacement reduction rate far away from the excavation surface.

[0077] Step 4: Drill holes from the excavated tunnel toward the drilling and blasting tunnel to be excavated, and install a hard rock displacement monitoring system for the drilling and blasting section in the holes.

[0078] like Figure 2 As shown in the right half, a borehole is drilled from the excavated tunnel to the direction of the drilling and blasting tunnel to be excavated, and the drilling includes three directions: up-inclined, nearly horizontal, and down-inclined. Multi-point displacement meters or fiber grating FRP smart bars are buried at preset positions in the corresponding boreholes to form a hard rock displacement monitoring system for the drilling and blasting section. It should be noted that the sensor (measuring point) closest to the side wall of the drilling and blasting tunnel in each borehole needs to be 0.3m-1m away from the side wall of the drilling and blasting tunnel. This can ensure that the sensor is arranged as close as possible to the maximum stress point obtained by numerical simulation, and can avoid damage by excavation. The sensor (measuring point) located on the central axis of the drilling and blasting tunnel is 0.1-1m away from the wall of the drilling and blasting tunnel, preferably 0.7m. The distance between two adjacent sensors (measuring points) in the same borehole is 1.5-2.5m, taking into account both the sensor layout cost and monitoring accuracy.

[0079] exist Figure 2 In the embodiment shown, some of the boreholes and displacement sensor layout positions of the hard rock displacement monitoring system of the drilling and blasting section are shown in Table 2. In Table 2, ZBB is a multi-point displacement meter drilling; ZBE is a fiber Bragg grating FRP intelligent reinforcement drilling.

[0080] Table 2 Some boreholes and sensor layout locations of the hard rock displacement monitoring system in the drilling and blasting section

[0081]

[0082]

[0083] There are 6 holes for multi-point displacement meter, with 36 sensors buried. There are 2 holes for fiber grating FRP smart reinforcement, each with 18 monitoring points.

[0084] Step 5: During the drilling and blasting excavation process, the drilling and blasting section hard rock displacement monitoring system is used to obtain the drilling and blasting section displacement monitoring data.

[0085] During the drilling and blasting excavation process, the multi-point displacement meter and fiber Bragg grating FRP smart reinforcement deployed in the drilling and blasting section are used to monitor the displacement data at different positions and at different times, and a displacement variation curve over time is plotted. In some embodiments, the displacement variation curve of the measuring point monitored by the multi-point displacement meter over time is as follows: Fig.10 shown.

[0086] Step 6: Analyze the evolution law of hard rock displacement in the drilling and blasting tunnel based on the displacement monitoring data of the drilling and blasting section.

[0087] from Fig.10The monitoring results shown in the figure show that due to the spatial effect of the tunnel face, the displacement increases stepwise after each excavation in the drilling and blasting section, and then the displacement growth decays exponentially, showing obvious creep characteristics. In some embodiments, the following piecewise function can be used to describe the evolution of the displacement u(t) of the measuring point of the multi-point displacement meter over time during the excavation of the drilling and blasting tunnel:

[0088]

[0089] Where u(t) represents the displacement of the measuring point at time T, which is the displacement value measured by the multi-point displacement meter in the drilling and blasting section. u0,u1,u2,...u N They are the displacement values ​​at the beginning of each stage, representing the initial displacement point in each time period, and N is a positive integer. K1, K2, K3, ... K N+1 are the displacement change influence coefficients of each stage, α1, α2, α3, ... α N+1 are the time influence coefficients of each stage, β1, β2, β3, ... β N+1 are the time adjustment factors of each stage, and these parameters can be obtained by fitting the monitoring data. N+1 is the time node of each stage, representing the start time of different stages. The piecewise function 4) is used to describe the change of u(t) over time, which is suitable for the sudden change characteristics of displacement during drilling and blasting excavation. The change curve of each stage may be different, reflecting the displacement response under different construction parameters or hard rock conditions. Through this piecewise model, the displacement changes measured by multi-point displacement meters during drilling and blasting excavation can be effectively described and predicted, helping engineers to conduct real-time monitoring and risk assessment.

[0090] Step 7: Guide the TBM and drilling and blasting excavation processes based on the hard rock displacement evolution analysis results of the TBM tunnel and drilling and blasting tunnel.

[0091] Based on the analysis results of the hard rock displacement evolution law of TBM tunnels and drill-blast tunnels, we can reasonably design blasting plans and construction plans, reasonably design tunnel shapes and directions, guide tunnel excavation sequence, guide support plan design, and conduct geological disaster risk warnings.

[0092] Specifically, the design of the blasting plan needs to comprehensively consider the following aspects: 1) Geological conditions: According to the geological overview, understand the rock properties, crack direction, groundwater conditions, etc., and select appropriate blasting parameters. 2) Support measures: Provide support in time before and after blasting to ensure the stability of hard rock and prevent collapse. 3) Construction monitoring: Use the hard rock displacement monitoring system of this application to monitor blasting displacement, evaluate the blasting effect and surrounding environmental safety, and adjust blasting parameters and support measures when necessary. 4) Emergency plan: Formulate detailed emergency plans and disposal measures for possible geological disasters (such as rock bursts, water gushing, etc.).

[0093] Based on the analysis results of the evolution of hard rock displacement in TBM tunnels and drill-and-blast tunnels, TBM or drill-and-blast can be selected for construction in different applicable scenarios. The TBM method performs better in hard rock and can maintain a high construction speed and stability, but special attention should be paid to support and groundwater treatment when encountering soft hard rock or poor geological conditions. The drill-and-blast method is more flexible in dealing with complex geological conditions and can adapt to different geological conditions by adjusting blasting parameters and support measures, but special attention should be paid to the stability and safety of hard rock in soft hard rock.

[0094] It is also possible to select appropriate tunnel shapes and directions based on the deformation characteristics and stress distribution of hard rock to ensure the stability and safety of the tunnel. First of all, the analysis of the evolution law of hard rock displacement is the basis of design. By analyzing the deformation characteristics and stress distribution of hard rock, we can understand the differentiated response characteristics of tunnels under different stress conditions. For example, when the lateral stress coefficient k>1, attention should be paid to the support of the top (bottom) plate of the tunnel; when k<1, attention should be paid to the support of both sides of the tunnel. In addition, the hard rock control of deep underground projects needs to consider the changes in the physical and mechanical properties of the rock mass and its self-healing ability, and adopt the pressure-yielding design technology to give full play to the vitality of hard rock and achieve the purpose of optimized design.

[0095] In underground engineering, TBM and drilling and blasting are two common hard rock excavation methods. Both methods may encounter geological disasters such as rock bursts during implementation. These disasters not only threaten the safety of construction workers, but may also lead to delays in project progress and increased costs. Therefore, the analysis of hard rock excavation response is crucial. This application analyzes the hard rock excavation response of TBM and drilling and blasting methods based on a hard rock displacement monitoring system, which can improve project safety and efficiency, as well as achieve effective prediction and prevention of geological disasters such as rock bursts.

[0096] The core of geological disaster risk warning based on the analysis results of hard rock displacement evolution law is to monitor and analyze small changes in hard rock in real time, so as to provide early warning. Analysis of hard rock displacement evolution law is the basis of geological disaster warning. This application deploys a hard rock displacement monitoring system in the TBM section and the drilling and blasting section, and analyzes the hard rock displacement evolution law based on the displacement monitoring data obtained during the TBM / drilling and blasting excavation process. It can detect geological disaster risks in advance, and effectively reduce casualties and property losses caused by geological disasters through a widely covered monitoring network and rapid response mechanism.

[0097] The hard rock displacement monitoring system of this application evaluates the damage and safety status of the hard rock in the tunnel by monitoring the displacement caused by hard rock fracture, thereby providing a basis for predicting and controlling disasters. By real-time monitoring of rock mass stability, potential safety hazards can be discovered and dealt with in a timely manner, geological disasters such as rock bursts can be avoided, and the safety of construction personnel and equipment can be guaranteed. According to the monitoring data, the construction plan can be adjusted, such as changing the excavation speed, support method, etc., to adapt to different geological conditions and reduce the occurrence of safety accidents. By accurately predicting geological disasters such as rock bursts, the construction schedule can be reasonably arranged to avoid project delays caused by emergencies, thereby improving construction efficiency. Combined with modern information technology, real-time transmission and processing of data can be realized, providing intelligent support for engineering management, and further improving the efficiency and accuracy of engineering management. This application conducts TBM and drilling and blasting hard rock excavation response analysis based on the hard rock displacement monitoring system, which can not only improve the safety of the project, optimize the construction plan, and improve the construction efficiency, but also realize intelligent management, providing important guarantees for the smooth implementation of underground projects.

[0098] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A hard rock internal displacement comparison monitoring method, characterized in that: include: Drill holes from the excavated tunnel toward the TBM tunnel to be excavated, and install the TBM section hard rock displacement monitoring system in the holes; During the TBM excavation process, the TBM segment hard rock displacement monitoring system is used to obtain TBM segment displacement monitoring data; Analyze the evolution law of hard rock displacement in TBM tunnels based on TBM segment displacement monitoring data; Drill holes from the excavated tunnel to the direction of the drilling and blasting tunnel to be excavated, and install a hard rock displacement monitoring system for the drilling and blasting section in the boreholes; During the drilling and blasting excavation process, the drilling and blasting section hard rock displacement monitoring system is used to obtain the drilling and blasting section displacement monitoring data; Analyze the evolution law of hard rock displacement in the drilling and blasting tunnel based on the displacement monitoring data of the drilling and blasting section; The analysis results of the hard rock displacement evolution law of TBM tunnels and drill and blast tunnels are used to guide the TBM and drill and blast excavation processes.

2. The hard rock internal displacement comparison monitoring method according to claim 1 is characterized in that: The method of drilling a hole from the excavated tunnel toward the TBM tunnel to be excavated and arranging a TBM section hard rock displacement monitoring system in the hole specifically includes: Drill holes from the excavated tunnel toward the TBM tunnel to be excavated. The drilling directions include up-inclined, nearly horizontal, and down-inclined. One or more of a multi-point displacement meter, a fiber grating FRP smart reinforcement and a sliding micrometer are buried at preset positions in corresponding boreholes to form a TBM section hard rock displacement monitoring system.

3. The hard rock internal displacement comparison monitoring method according to claim 2 is characterized in that: The method of burying one or more of a multi-point displacement meter, a fiber Bragg grating (FRP) smart rib and a sliding micrometer at a preset position in the corresponding borehole specifically includes: The distance between the sensor closest to the TBM tunnel sidewall in each borehole and the TBM tunnel sidewall is 0.1m-1m; The sensor located on the central axis of the TBM tunnel is 0.1-1m away from the TBM tunnel wall.

4. The hard rock internal displacement comparison monitoring method according to claim 1 is characterized in that: The analysis of the hard rock displacement evolution law of the TBM tunnel based on the TBM segment displacement monitoring data specifically includes: According to the TBM segment displacement monitoring data, the hard rock displacement of the TBM tunnel is divided into three stages: the slow growth stage of hard rock deformation before reaching the monitoring borehole, the rapid growth stage of deformation near the monitoring section, and the stable stage of hard rock deformation behind the monitoring section.

5. The hard rock internal displacement comparison monitoring method according to claim 4 is characterized in that: The analysis of the hard rock displacement evolution law of the TBM tunnel according to the TBM segment displacement monitoring data also includes: Using piecewise function To fit the relationship between the displacement D(t) of the multi-point displacement meter and the distance S(t) between the face and the borehole axis during TBM tunnel excavation; where t represents time; t0, t1, t2, ...t N+1 are the time nodes of each stage; D0tD1, D2, ..., D n are the displacement values ​​at the beginning of each stage; k1, k2, k3, ..., k n+1 are the displacement change rates in each stage respectively.

6. The hard rock internal displacement comparison monitoring method according to claim 5 is characterized in that: The distance S(t) between the tunnel face and the borehole axis is calculated using the formula Or S(t)=Kt+B for fitting; wherein K represents the slope of the S(t) curve, B represents the intercept; w represents the time factor, a represents the time factor coefficient, and b represents the exponential adjustment factor.

7. The hard rock internal displacement comparison monitoring method according to claim 1 is characterized in that: The method of drilling a hole from the excavated tunnel toward the drilling and blasting tunnel to be excavated and arranging a hard rock displacement monitoring system for the drilling and blasting section in the hole specifically includes: Drill holes from the excavated tunnel in a direction perpendicular to the excavation direction of the tunnel to be excavated. The drilling directions include upward, nearly horizontal, and downward. One or more of a multi-point displacement meter, a fiber grating FRP smart rib and a sliding micrometer are buried at preset positions in corresponding boreholes to form a hard rock displacement monitoring system for the drilling and blasting section.

8. The hard rock internal displacement comparison monitoring method according to claim 7 is characterized in that: The method of burying one or more of a multi-point displacement meter, a fiber Bragg grating (FRP) smart rib and a sliding micrometer at a preset position in the corresponding borehole specifically includes: The distance between the sensor closest to the side wall of the drilling and blasting tunnel in each borehole and the side wall of the drilling and blasting tunnel is 0.3m-1m; The sensor located on the central axis of the drilling and blasting tunnel is 0.3-1m away from the wall of the drilling and blasting tunnel.

9. The hard rock internal displacement comparison monitoring method according to claim 8, characterized in that: The analysis of the hard rock displacement evolution law of the drilling and blasting tunnel based on the displacement monitoring data of the drilling and blasting section specifically includes: According to the analysis of the displacement monitoring data of the drilling and blasting section, the displacement showed a step increase after each round of excavation in the drilling and blasting tunnel, and then the displacement growth decayed exponentially.

10. The hard rock internal displacement comparison monitoring method according to claim 9, characterized in that: The analysis of the hard rock displacement evolution law of the drilling and blasting tunnel based on the displacement monitoring data of the drilling and blasting section specifically includes: Using piecewise function To fit the curve of the displacement u(t) of the multi-point displacement meter over time T during the drilling and blasting tunnel excavation process; where T0, T1, T2, ... T N+1 are the time nodes of each stage; u0,u1,u2,...u N are the displacement values ​​at the beginning of each stage; K1, K2, K3, ... K N+1 are the displacement change influence coefficients of each stage; α1, α2, α3, ... α N+1 are the time influence coefficients of each stage; β1, β2, β3, ... β N+1 are the time adjustment factors for each stage respectively.

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