An intelligent evaluation and prediction method for blasting quality in drill-and-blast tunnels

Abstract

The present invention belongs to the technical field of tunnel engineering construction and provides an intelligent evaluation and prediction method for the blasting quality of a drill-and-blast tunnel. The method comprises the following steps: obtaining the contour of the tunnel after blasting, comparing it with the designed contour of the tunnel to evaluate the shape difference, and obtaining the under-excavation rate P of the tunnel after blasting. q and over-excavation rate P c Calculate the actual volume of rock blasting after blasting, compare it with the theoretical value of surrounding rock volume under single cycle footage, and obtain the difference rate P of rock blasting volume after blasting tunnel. b Simulate the tunnel blasting effect, obtain the simulated stress value of the surrounding rock based on the simulated tunnel blasting effect, compare the simulated stress value of the surrounding rock with the initial ground stress of the surrounding rock to evaluate the surrounding rock stability, and calculate the stress difference rate P after blasting f ; The under-excavation rate P q , over-excavation rate P c , rockburst volume difference rate P b and stress difference rate P f Perform coupling calculation to obtain the blasting quality evaluation value P of the drill-blast tunnel z The present invention takes both the tunnel shape and the surrounding rock stability into consideration, and can comprehensively and accurately evaluate the blasting quality of drill-and-blast tunnels.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel engineering construction, and in particular relates to an intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel. Background Art

[0002] The drill-and-blast method is widely used in tunnel construction due to its wide applicability, flexibility, reliability, and cost-effectiveness. It is also the most commonly used method for railway tunnel construction in my country. Evaluating the blasting quality of drill-and-blast tunnels is crucial to inform subsequent blasting plan design.

[0003] Existing technical research mainly focuses on using the hierarchical analysis method to establish an evaluation index system, combining the index weights to evaluate blasting quality, or optimizing blasting parameters. However, none of them considers the deformation and stress characteristics of the surrounding rock after tunnel blasting, nor does it use intelligent algorithms to predict blasting quality. Summary of the Invention

[0004] The purpose of the present invention is to provide an intelligent evaluation and prediction method for the blasting quality of a drill-and-blast tunnel to solve the above problems.

[0005] To achieve the above object, the present invention provides the following solution: an intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel, comprising the following steps:

[0006] Obtain the tunnel contour after blasting, compare it with the tunnel design contour to evaluate the shape difference, and obtain the under-excavation rate P of the tunnel after blasting based on the shape difference evaluation. q and over-excavation rate P c ;

[0007] Calculate the actual volume of rock burst after blasting, compare it with the theoretical value of surrounding rock volume under single cycle footage, and obtain the difference rate P of rock burst volume after blasting tunnel. b ;

[0008] Simulate the tunnel blasting effect, obtain the surrounding rock simulated stress value based on the simulated tunnel blasting effect, compare the surrounding rock simulated stress value with the initial ground stress of the surrounding rock to evaluate the surrounding rock stability, and calculate the stress difference rate P after blasting f ;

[0009] The under-excavation rate P q , over-excavation rate P c , rockburst volume difference rate P b and stress difference rate P f Perform coupling calculation to obtain the blasting quality evaluation value P of the drill-blast tunnel z , according to P zIt is important to optimize the drilling arrangement and explosive filling of the current blasting section.

[0010] Preferably, the obtained tunnel blasting contour is compared with the tunnel design contour to perform shape difference evaluation, and based on the shape difference evaluation, the undercut rate P of the tunnel after blasting is obtained. q and over-excavation rate P c The steps include:

[0011] Calculate the tunnel design net area S based on the tunnel design shape outline;

[0012] Scan the point cloud data of the tunnel contour after blasting to obtain the actual shape contour of the tunnel;

[0013] The tunnel design shape outline and the actual shape outline are overlapped to obtain the tunnel over-break and under-break areas. The sum of the under-break areas based on the over-break and under-break areas is S. q , the sum of the over-excavation area is S c , through the net area S, the sum of the undercut area S q , the sum of over-excavation area S c Calculate the undercut rate P q and over-excavation rate P c .

[0014] Preferably, the undercut rate P q The calculation formula is: q =S q / S, over-excavation rate P c The calculation formula is: c =S c / S.

[0015] Preferably, the actual blasting volume after blasting is calculated and evaluated with the theoretical value of the surrounding rock volume under a single cycle footage to obtain the blasting volume difference rate P of the tunnel blasting. b The steps include:

[0016] Calculate the theoretical value V of the surrounding rock volume under a single cycle of tunnel footage l ;

[0017] After the tunnel is blasted, the actual volume of the blasted rock V s Calculate the rockburst volume difference rate P b .

[0018] Preferably, the rockburst volume difference rate P b The calculation formula is: b =(V l -V s ) / V l .

[0019] Preferably, the simulated tunnel blasting effect is used to obtain the simulated stress value of the surrounding rock based on the simulated tunnel blasting effect, and the simulated stress value of the surrounding rock is compared with the initial ground stress of the surrounding rock to evaluate the stability of the surrounding rock, and the stress difference rate P after blasting is calculated. f The steps include:

[0020] Use three-dimensional simulation software to build a numerical model and impose corresponding constraints on the model boundaries;

[0021] Combined with the actual blasting plan on site, the corresponding blasthole layout diagram is constructed, and then the blasting effect on site is simulated, and the simulated stress value F of the surrounding rock is obtained based on the simulation results. s ;

[0022] Obtain the initial ground stress F of the surrounding rock o , according to the simulated stress F of the surrounding rock s and initial ground stress F o , calculate the stress difference rate P of the surrounding rock after blasting f .

[0023] Preferably, the stress difference rate P of the surrounding rock after blasting f The calculation formula is:

[0024] P f =(F s -F o ) / F o .

[0025] Preferably, the undercut rate P q , over-excavation rate P c , rockburst volume difference rate P b and stress difference rate P f Perform coupling calculation to obtain the blasting quality evaluation value P of the drill-blast tunnel z The steps include:

[0026] Tunnel undercut rate P q and tunnel over-excavation rate P c Perform coupling calculations to obtain the tunnel shape difference evaluation value P1;

[0027] Volume difference rate of rock burst P b The tunnel shape difference evaluation value P1 is coupled with the tunnel shape evaluation value P x ;

[0028] The stress difference rate P after blasting f and shape evaluation value P x Perform coupling calculations to finally obtain the blasting quality evaluation value P of the drill-blast tunnel. z .

[0029] Preferably, the blasting quality evaluation value P of the drill-blast tunnelz When the value is greater than or equal to 0.9 and less than 1, the tunnel blasting quality is considered to be excellent.

[0030] Compared with existing technologies, this invention offers the following advantages and technical effects: The evaluation and prediction method simultaneously considers both tunnel shape and surrounding rock stability, enabling comprehensive and accurate evaluation of tunnel blasting quality and intelligent prediction of subsequent drilling and blasting quality. Based on the prediction results and evaluation criteria, the blasting quality can be judged. If the blasting quality is low, the blasting plan or blasthole layout can be optimized promptly. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 This is a schematic diagram of the tunnel shape outline superposition of the present invention;

[0033] Figure 2 Schematic diagram of radial and circumferential directions of the tunnel of the present invention;

[0034] Figure 3 This is a blasthole arrangement diagram of the present invention; DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1:

[0038] Reference Figure 1-Figure 3 The present invention provides an intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel, the steps of which are as follows:

[0039] Obtain the tunnel contour after blasting, compare it with the tunnel design contour to evaluate the shape difference, and obtain the under-excavation rate P of the tunnel after blasting based on the shape difference evaluation. q and over-excavation rate P c ;

[0040] Calculate the actual volume of rock burst after blasting, compare it with the theoretical value of surrounding rock volume under single cycle footage, and obtain the difference rate P of rock burst volume after blasting tunnel. b ;

[0041] Simulate the tunnel blasting effect, obtain the surrounding rock simulated stress value based on the simulated tunnel blasting effect, compare the surrounding rock simulated stress value with the initial ground stress of the surrounding rock to evaluate the surrounding rock stability, and calculate the stress difference rate P after blasting f ;

[0042] The under-excavation rate P q , over-excavation rate P c , rockburst volume difference rate P b and stress difference rate P f Perform coupling calculation to obtain the blasting quality evaluation value P of the drill-blast tunnel z , according to P z It is important to optimize the drilling arrangement and explosive filling of the current blasting section.

[0043] Before further optimizing the plan and conducting evaluation and prediction, the following preparations are required:

[0044] ① Based on geological survey reports, design documents, and on-site investigations, organize and collect tunnel geometry and geological data. Geometric information primarily refers to tunnel cross-sectional dimensions, such as tunnel height and width; geological data primarily includes topography, geological structure, surrounding rock type, hydrogeology, and adverse geological conditions, such as tunnel depth and groundwater depth.

[0045] ② Combine the geometric dimensions of the tunnel and the type of surrounding rock to find similar projects at home and abroad, and accumulate basic data for intelligent evaluation and prediction.

[0046] Further optimize the scheme, obtain the tunnel blasting contour, compare it with the tunnel design contour to evaluate the shape difference, and obtain the under-excavation rate P of the tunnel after blasting based on the shape difference evaluation. q and over-excavation rate P c The steps include:

[0047] Calculate the tunnel design net area S based on the tunnel design shape outline;

[0048] Scan the point cloud data of the tunnel contour after blasting to obtain the actual shape contour of the tunnel;

[0049] The tunnel design shape outline and the actual shape outline are overlapped to obtain the tunnel over-break and under-break areas. The sum of the under-break areas obtained based on the over-break and under-break areas is S. q , the sum of the over-excavation area is S c , through the net area S, the sum of the undercut area Sq , the sum of over-excavation area S c Calculate the undercut rate P q and over-excavation rate P c .

[0050] Further optimization of the scheme, under-excavation rate P q The calculation formula is: q =S q / S, over-excavation rate P c The calculation formula is: c =S c / S.

[0051] In this embodiment, the specific evaluation process of shape difference is as follows:

[0052] ① Based on the tunnel design file, determine the design shape outline of the tunnel and calculate the design net area S of the tunnel.

[0053] ② Use laser scanning or image acquisition technology to obtain point cloud data of the actual shape of the tunnel after blasting, and perform digital model display to obtain the actual shape outline of the tunnel.

[0054] ③ Overlap the tunnel's design shape and actual shape (e.g. Figure 1 As shown in Figure 2, the over-break and under-break areas of the tunnel can be obtained, thereby evaluating the tunnel blasting quality based on the differences in tunnel shapes.

[0055] ④ The area within the tunnel design shape outline represents the under-excavation part of the tunnel, and the sum of the over-excavation area is expressed as S q The area outside the tunnel design shape outline represents the tunnel over-excavation. The sum of the over-excavation area is denoted by S c express.

[0056] ⑤ Calculate the tunnel under-excavation rate P q and over-excavation rate P c The smaller the over-break and under-break rate, the better the tunnel blasting quality, and vice versa.

[0057] Further optimize the scheme, calculate the actual volume of blasted rock after blasting, and evaluate the volume of blasted rock compared with the theoretical value of surrounding rock volume under single cycle footage, and obtain the volume difference rate P of blasted rock after blasting tunnel. b The steps include:

[0058] Calculate the theoretical value V of the surrounding rock volume under a single cycle of tunnel footage l ;

[0059] After the tunnel is blasted, the actual volume of the blasted rock V s Calculate the rockburst volume difference rate P b .

[0060] Further optimization scheme, the rock burst volume difference rate P b The calculation formula is:

[0061] P b =(V l -V s ) / V l ,

[0062] In this embodiment, the specific process of evaluating the rock burst volume is as follows:

[0063] ① Combine the tunnel section size and excavation footage to calculate the theoretical value of the surrounding rock volume under the tunnel single cycle footage V l , where V l The calculation formula is cross-sectional area ╳ single cycle footage length L.

[0064] ② After the tunnel is blasted, the actual value of the blast volume V is calculated based on the slag discharge vehicle s , where V s =Number of slag-discharging vehicles N╳Transport volume of a single slag-discharging vehicle V c .

[0065] ③Calculate the rockburst volume difference rate P b =(V l -V s ) / V l .

[0066] ④ When the volume difference rate of the rock burst is P b When it is greater than 0, it means the tunnel is under-excavated, otherwise it is over-excavated. b The smaller the absolute value of is, the smaller the over-break and under-break phenomenon is, and the better the tunnel blasting quality in terms of blasting rock volume is, and vice versa.

[0067] Further optimize the scheme, simulate the tunnel blasting effect, obtain the simulated stress value of the surrounding rock based on the simulated tunnel blasting effect, compare the simulated stress value of the surrounding rock with the initial ground stress of the surrounding rock to evaluate the surrounding rock stability, and calculate the stress difference rate P after blasting f The steps include:

[0068] Use three-dimensional simulation software to build a numerical model and impose corresponding constraints on the model boundaries;

[0069] Combined with the actual blasting plan on site, the corresponding blasthole layout diagram is constructed, and then the blasting effect on site is simulated, and the simulated stress value F of the surrounding rock is obtained based on the simulation results. s ;

[0070] Obtain the initial ground stress F of the surrounding rock o , according to the simulated stress F of the surrounding rock s and initial ground stress F o , calculate the stress difference rate P of the surrounding rock after blasting f.

[0071] Further optimization scheme, the stress difference rate P of surrounding rock after blasting f The calculation formula is:

[0072] P f =(F s -F o ) / F o ,

[0073] In this embodiment, specifically, the surrounding rock stability evaluation process is as follows:

[0074] ① Use three-dimensional simulation software to construct a numerical model and impose corresponding constraints on the model boundaries.

[0075] ② Combined with geological survey reports, laboratory results and supplementary tests, determine the basic physical and mechanical parameters of the model, such as surrounding rock density, shear modulus, cohesion, etc. Then select the corresponding constitutive model and determine the corresponding constitutive model parameters, such as strain rate, damage coefficient, failure strain, etc.

[0076] ③ Combined with the actual blasting plan on site, arrange the corresponding blasthole layout diagram, and then simulate the blasting effect of explosives on site.

[0077] ④Numerical analysis: when the actual number of calculation steps of the numerical simulation exceeds the set number of steps, the model calculation stops.

[0078] ⑤According to the model calculation results, obtain the stress and deformation data of the surrounding rock.

[0079] ⑥ According to the surrounding rock geological survey report, determine the initial ground stress F of the surrounding rock o ; According to the numerical simulation results, determine the simulated stress value F of the surrounding rock after blasting s , calculate the stress difference rate P of the surrounding rock after blasting f =(F s -F o ) / F o When the stress difference rate is greater than 0, it means the tunnel is over-excavated, otherwise it is under-excavated. f The smaller the absolute value, the smaller the difference between the surrounding rock stress value and the initial ground stress after tunnel blasting, the lower the degree of surrounding rock disturbance, which reflects the better quality of tunnel blasting, and vice versa.

[0080] Further optimization scheme, through the surrounding rock radial (such as Figure 2The deformation evolution pattern (shown in Figure 2) can be used to determine the extent of blasting disturbance. Surrounding rock deformation gradually decreases along the tunnel radial direction and approaches zero. When the surrounding rock stress or deformation zone reaches zero, the corresponding location is the boundary between blasting disturbance and undisturbed conditions. The area within the boundary is the tunnel blasting influence range, while the area outside the boundary is the tunnel blasting undisturbed range. A smaller disturbance range indicates better blasting quality, and vice versa.

[0081] To further optimize the solution, in step S5, the coupling calculation formula is as follows:

[0082] (1)

[0083] Where M is the analysis result after coupling factor A and factor B, α and β represent the weight coefficients of factor A and factor B respectively, and α and β are determined by expert survey method or Delphi method.

[0084] Specifically, the method for determining the values ​​of α and β can be a qualitative method, that is, experts give specific numbers for α and β based on their personal experience, and ensure that the sum of the two values ​​is 1;

[0085] A quantitative value-taking method can also be adopted, which is to use game theory to determine specific data.

[0086] To further optimize the solution, in step S5, the coupling calculation process is as follows:

[0087] Using formula (1) to calculate the tunnel undercut rate P q and tunnel over-excavation rate P c Perform coupling calculation to obtain the tunnel shape difference evaluation value P1, where the tunnel undercut rate P q Or tunnel over-excavation rate P c One of them is brought into A, and the other into B;

[0088] The rockburst volume difference rate P is calculated using formula (1). b The tunnel shape difference evaluation value P1 is coupled with the tunnel shape evaluation value P x , where the rockburst volume difference rate P b Or one of the shape difference evaluation values ​​P1 is substituted into A and the other into B;

[0089] The stress difference rate P after blasting is calculated using formula (1). f and shape evaluation value P x Perform coupling calculations to finally obtain the blasting quality evaluation value P of the drill-blast tunnel. z , where the stress difference rate P f Or shape evaluation value P x One of them is brought into A and the other into B.

[0090] Further optimization scheme, the blasting quality evaluation value P of the drill-blast tunnel z The value of in the range of [0.9, 1.0) is considered to be excellent tunnel blasting quality.

[0091] To further optimize the scheme, the intelligent evaluation and prediction process of blasting quality is as follows:

[0092] ①Build a basic database, including the cross-sectional dimensions of the tunnel, the tunnel depth, the surrounding rock type, the type of explosives, the quantity of explosives, and the blasting quality evaluation value P of the drill-and-blast tunnel. z wait.

[0093] ② 80% of the data in the basic database is used to train the intelligent model, which includes artificial neural networks, particle swarm optimization algorithms, and gray wolf algorithms.

[0094] ③ Use the remaining 20% ​​of the data in the basic database to verify the accuracy of the trained intelligent model. When the relative deviation between the predicted result and the actual result is less than 10%, the intelligent model training result can be considered to meet the requirements.

[0095] ④ Use the trained intelligent model to evaluate the blasting quality of subsequent drilling and blasting tunnels. The input basic data includes the cross-sectional dimensions of the tunnel, the tunnel burial depth, the surrounding rock type, the type of explosives, the amount of explosives, etc. The output result is the blasting quality evaluation value P of the drilling and blasting tunnel. z .

[0096] Specifically, according to P z The numerical rating criteria are as follows:

[0097]

[0098] Example 2:

[0099] This embodiment is a specific application of the first embodiment:

[0100] 4.1 Evaluation Preparation

[0101] The example tunnel is a one-way two-lane highway tunnel with a tunnel depth of 250.0 m and an excavation section of 200.0 m. 2 The surrounding rock type is shale interbedded with mudstone. The blasting test section utilizes a two-step construction method, using a cycle of segmented blasting to rapidly expand the cross-section. A single blasting cycle achieves a 2.0 m advance. Air-interval charging is planned for peripheral and auxiliary holes, while bottom continuous charging is planned for other blastholes. All blastholes utilize reverse blasting, using emulsion explosives.

[0102] 4.2 Tunnel shape evaluation

[0103] (1) Shape difference evaluation

[0104] ① Based on the tunnel design file, determine the design shape of the tunnel and calculate the tunnel's net design area S = 200.0m 2 .

[0105] ② Use laser scanning or image acquisition technology to obtain point cloud data of the actual shape of the tunnel after blasting, and perform digital model display to obtain the actual shape outline of the tunnel.

[0106] ③ By overlapping the designed shape of the tunnel with the actual shape outline, the over-break and under-break areas of the tunnel can be obtained, thereby evaluating the tunnel blasting quality based on the difference in tunnel shape.

[0107] ④ The area within the tunnel design shape outline represents the under-excavation part of the tunnel, and the sum of the over-excavation area S q =15.0m 2 The area outside the tunnel design shape represents the tunnel over-excavation area. The sum of the over-excavation areas S c =20.0m 2 .

[0108] ⑤ Calculate the tunnel under-excavation rate P q =S q / S=15 / 200=0.075 and over-excavation rate P c =S c / S=20 / 200=0.10.

[0109] ⑥Use formula (1) to couple the under-excavation rate and over-excavation rate of the tunnel, and the weight coefficients α and β are 0.4 and 0.6 respectively.

[0110] The tunnel shape difference evaluation value P1=0.4╳0.075+0.6╳0.1=0.09 is obtained.

[0111] (2) Evaluation of rockburst volume

[0112] ① Combine the tunnel section size and excavation footage to calculate the theoretical value of the surrounding rock volume under the tunnel single cycle footage V l = Cross-sectional area ╳ Single cycle footage length L = 200 ╳ 2.0 = 400m 3 .

[0113] ② After the tunnel is blasted, the actual value of the blast volume V is calculated based on the slag discharge vehicle s =Number of slag-discharging vehicles N╳Transport volume of a single slag-discharging vehicle V c =18╳20=360m 3 .

[0114] ③Calculate the rockburst volume difference rate P b =(V l -V s ) / Vl =(400-360) / 400=0.1.

[0115] ④ Using formula (1), the shape difference evaluation value P1 and the rockburst volume difference rate P b The coupled calculation is performed, and the weight coefficients α and β are set to 0.6 and 0.4 respectively, and then the shape evaluation value P of the tunnel is obtained. x =0.6╳0.09+0.4╳0.1=0.094.

[0116] 4.3 Surrounding rock stability evaluation

[0117] (1) A numerical model was constructed using three-dimensional simulation software, and strict displacement constraints were imposed on the boundaries, i.e., the left and right boundaries constrained the X-direction displacement, the upper and lower boundaries constrained the Y-direction displacement, and the front and rear boundaries constrained the Z-direction displacement. Non-reflection boundary conditions were also used to eliminate the influence of boundary reflection waves.

[0118] (2) According to the actual blasting plan on site, arrange the corresponding blasthole layout diagram, and then simulate the blasting effect of explosives on site. Figure 3 shown.

[0119] (3) Determine the initial ground stress F of the surrounding rock based on the surrounding rock geological survey report o =25.0MPa,

[0120] (4) According to the numerical simulation results, determine the simulated stress value F of the surrounding rock after blasting s =23.0Mpa, calculate the stress difference rate of surrounding rock after blasting

[0121] P f =(F s -F o ) / F o =(23-25) / 25=-0.08.

[0122] (5) The range of blasting disturbance is determined by the evolution law of radial deformation of the surrounding rock. When the radial distance of the surrounding rock exceeds 2.5 m from the tunnel outline, the surrounding rock deformation decreases to 0, indicating that the range of blasting disturbance of the surrounding rock is 2.0 m outside the tunnel outline.

[0123] (6) Using formula (1) to evaluate the tunnel shape value P x and surrounding rock stability evaluation value P f The coupled calculation is performed, and the weight coefficients α and β are set to 0.5 and 0.5 respectively, and the blasting quality evaluation value P of the drill-blast tunnel is finally obtained. z =0.5╳0.094+0.5╳0.08=0.087.

[0124] 4.4 Intelligent Evaluation and Prediction of Blasting Quality

[0125] (1) Construct a basic database, including a total of 100 pairs of data.

[0126] (2) 80% of the data in the basic database is used to train the artificial neural network model.

[0127] (3) The accuracy of the trained artificial neural network is verified using the remaining 20% ​​of the data in the basic database. When the relative deviation rate between the predicted results and the actual results is 5.0% and is less than 10%, the training results of the intelligent model can be considered to meet the requirements.

[0128] (4) The trained artificial neural network model is used to evaluate the blasting quality of subsequent drilling and blasting tunnels.

[0129] (5) The cross-sectional dimension of the tunnel is 200.0m 2 The tunnel depth is 250m, the surrounding rock type is shale mixed with mudstone, and the explosive type is emulsion explosive. z =0.085.

[0130] (6) According to Table 1, the blasting quality of the drill-and-blast tunnel is good.

[0131] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0132] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. An intelligent evaluation and prediction method for blasting quality of drill-and-blast tunnels, characterized in that: The steps are as follows: Obtain the tunnel contour after blasting, compare it with the tunnel design contour to evaluate the shape difference, and obtain the under-excavation rate P of the tunnel after blasting based on the shape difference evaluation. q and over-excavation rate P c ; Calculate the actual volume of rock burst after blasting, compare it with the theoretical value of surrounding rock volume under single cycle footage to evaluate the rock burst volume, and obtain the rock burst volume difference rate P after blasting tunnel. b ; Simulate the tunnel blasting effect, obtain the surrounding rock simulated stress value based on the simulated tunnel blasting effect, compare the surrounding rock simulated stress value with the initial ground stress of the surrounding rock to evaluate the surrounding rock stability, and calculate the stress difference rate P after blasting f ; The under-excavation rate P q , over-excavation rate P c , rockburst volume difference rate P b and stress difference rate P f Perform coupling calculation to obtain the blasting quality evaluation value P of the drill-blast tunnel z , according to P z Optimize the drilling arrangement and explosive filling of the current blasting section; The coupling calculation formula is as follows: （1） Where M is the analysis result after the coupling of factors A and B, α and β represent the weight coefficients of factors A and B respectively, and α and β are determined by expert survey method or Delphi method; The method for determining the values ​​of α and β is qualitative, that is, experts give specific numbers for α and β based on their personal experience, and ensure that the sum of the two values ​​is 1; The process of the coupling calculation is as follows: Using formula (1) to calculate the tunnel undercut rate P q and tunnel over-excavation rate P c Perform coupling calculation to obtain the tunnel shape difference evaluation value P1, where the tunnel undercut rate P q Or tunnel over-excavation rate P c One of them is brought into A, and the other into B; The rockburst volume difference rate P is calculated using formula (1). b The tunnel shape difference evaluation value P1 is coupled with the tunnel shape evaluation value P x , where the rockburst volume difference rate P b Or one of the shape difference evaluation values ​​P1 is substituted into A and the other into B; The stress difference rate P after blasting is calculated using formula (1). f and shape evaluation value P x Perform coupling calculations to finally obtain the blasting quality evaluation value P of the drill-blast tunnel. z , where the stress difference rate P f Or shape evaluation value P x One of them is brought into A and the other into B.

2. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 1 is characterized by: The obtained tunnel blasting contour is compared with the tunnel design contour to evaluate the shape difference, and the under-excavation rate P of the tunnel after blasting is obtained based on the shape difference evaluation. q and over-excavation rate P c The steps include: Calculate the tunnel design net area S based on the tunnel design shape outline; Scan the point cloud data of the tunnel contour after blasting to obtain the actual shape contour of the tunnel; The tunnel design shape outline and the actual shape outline are overlapped to obtain the tunnel over-break and under-break areas. The sum of the under-break areas obtained based on the over-break and under-break areas is S. q , the sum of the over-excavation area is S c , through the net area S, the sum of the undercut area S q , the sum of over-excavation area S c Calculate the undercut rate P q and over-excavation rate P c .

3. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 2 is characterized by: Under-excavation rate P q The calculation formula is: q =S q / S, over-excavation rate P c The calculation formula is: c =S c / S.

4. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 1 is characterized by: The actual volume of blasted rock after the blasting is calculated and compared with the theoretical value of the surrounding rock volume under a single cycle footage to evaluate the blasted rock volume and obtain the blasted rock volume difference rate P after the blasting tunnel. b The steps include: Calculate the theoretical value V of the surrounding rock volume under a single cycle of tunnel footage l ; After tunnel blasting, the blasting rock volume difference rate P is calculated based on the actual volume of the blasted rock Vs b .

5. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 4 is characterized by: Rockburst volume difference rate P b The calculation formula is: b =(V l -V s ) / V l .

6. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 1 is characterized by: The simulated tunnel blasting effect is used to obtain the simulated stress value of the surrounding rock based on the simulated tunnel blasting effect, and the surrounding rock stability is evaluated by comparing the simulated stress value of the surrounding rock with the initial ground stress of the surrounding rock. The stress difference rate P after blasting is calculated. f The steps include: Use three-dimensional simulation software to build a numerical model and impose corresponding constraints on the model boundaries; Combined with the actual blasting plan on site, the corresponding blasthole layout diagram is constructed, and then the blasting effect on site is simulated, and the simulated stress value F of the surrounding rock is obtained based on the simulation results. s ; Obtain the initial ground stress F of the surrounding rock o , according to the simulated stress F of the surrounding rock s and initial ground stress F o , calculate the stress difference rate P of the surrounding rock after blasting f .

7. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 6, characterized in that: Stress difference rate P of surrounding rock after blasting f The calculation formula is: P f =(F s -F o ) / F o 。 8. The intelligent evaluation and prediction method for blasting quality of a drill-and-blast tunnel according to claim 1 is characterized by: Blasting quality evaluation value P of drill-and-blast tunnel z When the value is greater than or equal to 0.9 and less than 1, the tunnel blasting quality is considered to be excellent.

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