Fault fracture zone roadway surrounding rock reinforcement engineering exploration and injection effect evaluation method

Abstract

The invention relates to the technical field of underground surrounding rock engineering, in particular to a fault fracture zone roadway surrounding rock reinforcement engineering exploration and injection effect evaluation method. The method comprises the following steps: acquiring a solid pipe quality score, a slurry performance parameter score, a drilling hole depth score, a drilling track score and a logging score; the drilling engineering is evaluated according to the pipe fixing quality score, the slurry performance parameter score, the drilling hole depth score, the drilling track score and the logging score; after the drilling engineering is qualified, grouting is conducted, and the grouting quality of each grouting hole is evaluated according to the grouting end pressure, the grouting end pump amount, the grout injection amount and the rock-soil body permeability; and after the grouting quality of all the grouting holes is evaluated to be qualified, the surrounding rock reinforcement effect of the fault treatment area is evaluated according to the geophysical detection result, the water inflow and the rock core recovery rate. The method is suitable for coal fields with complex fracture structure development, and can effectively control the engineering construction quality and reasonably and accurately evaluate the fault fracture zone roadway surrounding rock reinforcement effect.

Description

Technical Field

[0001] The invention relates to the technical field of underground surrounding rock engineering, and in particular to a method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel. Background Art

[0002] Coal is an important energy source. In some coal production bases with rich coal resources, many faults of different scales, types and orientations have developed in the long-term geological evolution process, forming a complex fault structure system. With the progress of coal mining, geological conditions have become more and more complex, especially the existence of fault structures, which are closely related to groundwater flow, current geothermal field distribution, gas occurrence, mining impact, etc., which seriously affect and hinder the production and construction of coal mines.

[0003] With the continuous improvement of drilling equipment and technology, the use of advanced drilling equipment to construct multiple groups of horizontal multi-branch directional boreholes in the ground treatment area, conduct advance exploration of the working face tunnels in the reserve mining area and carry out regional treatment has been widely promoted and applied. In the process of drilling and treatment, it is necessary to evaluate the quality of drilling and treatment. In the existing technology, fault reinforcement treatment is only a post-evaluation of the treatment effect after grouting, and the whole process of exploration and injection engineering quality and fault reinforcement effect has not yet formed a systematic and complete evaluation method, and there is a defect of inaccurate subjective evaluation results. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a method for evaluating the effect of exploration and injection in the surrounding rock reinforcement engineering of a fault fracture zone tunnel. The technical scheme adopted is as follows:

[0005] An embodiment of the present invention provides a method for evaluating the effect of exploration and injection in a surrounding rock reinforcement project of a fault fracture zone tunnel, the method comprising:

[0006] Obtaining the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and mud logging score of the drilling project in the fault management area; evaluating the drilling project based on the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and mud logging score;

[0007] After the drilling project is qualified, grouting is carried out, and the grouting quality of each grouting hole is evaluated according to the grouting end pressure, grouting end pump volume, slurry injection volume and rock and soil permeability;

[0008] After the grouting quality of all grouting holes is evaluated as qualified, the surrounding rock reinforcement effect of the fault control area is evaluated using geophysical detection results, water inflow and core sampling rate.

[0009] Preferably, the solid pipe quality score includes:

[0010] Obtain the solid pipe quality score. When the pressure drop rate is greater than the first threshold, the solid pipe quality score is 0 points; when the pressure drop rate is within the first range, it is recorded as 1 point; when the pressure drop rate is within the second range, it is recorded as 2 points; when the pressure drop rate is less than or equal to the second threshold, it is recorded as 3 points.

[0011] Preferably, the mud performance parameter scoring includes:

[0012] The mud performance parameters include mud viscosity, mud density and mud pH, and the design range values ​​of mud viscosity, mud density and mud pH are obtained; within the design range values, the scores of mud viscosity, mud density and mud pH are recorded as 3 points; if they exceed or fall below the design range values ​​by 5%, the scores of mud viscosity, mud density and mud pH are recorded as 2 points; if they exceed or fall below the design range values ​​by 5% to 10%, the scores of mud viscosity, mud density and mud pH are recorded as 1 point; if they exceed or fall below the design range values ​​by 10%, the scores of mud viscosity, mud density and mud pH are recorded as 0 points; the weighted sum of the scores of mud viscosity, mud density and mud pH is obtained to obtain the mud performance parameter score.

[0013] Preferably, the drilling depth scoring includes:

[0014] When the actual borehole depth on both sides of the fault exceeds the maximum width of the water-bearing or water-conducting fault water-blocking coal (rock) pillar, the borehole depth score is recorded as 3 points, which is rated as excellent;

[0015] When the actual borehole depth exceeds the maximum width of the water-bearing or water-conducting fault water-blocking coal (rock) pillar on one side of the fault, the borehole depth score is recorded as 2 points, which is rated as good;

[0016] When the actual borehole depth on both sides of the fault exceeds the minimum width of the water-bearing or water-conducting fault water-blocking coal (rock) pillar, the borehole depth score is recorded as 1 point and is evaluated as qualified;

[0017] When the actual borehole depth on both sides of the fault does not exceed the minimum width of the water-bearing or water-conducting fault anti-waterproof coal (rock) pillar, the borehole depth score is recorded as 0 points and is assessed as unqualified.

[0018] Preferably, the drilling trajectory scoring includes:

[0019] If the deviation of the actual drilling trajectory of the horizontal branch hole compared with the designed trajectory is within the first deviation range, the drilling trajectory score is recorded as 3 points, which is evaluated as excellent; if the deviation is within the second deviation range compared with the designed trajectory, the drilling trajectory score is recorded as 2 points, which is evaluated as good; if the deviation is within the third deviation range compared with the designed trajectory, the drilling trajectory score is recorded as 1 point, which is evaluated as qualified; if the slurry diffusion radius fails to form a grouting circle within the plastic zone of the tunnel or the deviation from the designed trajectory is above the maximum deviation, the drilling trajectory score is recorded as 0 point, which is evaluated as unqualified.

[0020] Preferably, the mud logging scoring includes:

[0021] The logging includes cuttings logging, drilling logging and while drilling gamma value, which are scored according to the design requirement range corresponding to each logging; if the logging includes cuttings logging, drilling logging and while drilling gamma value, they are all within the design range, and the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 3 points; if they are lower than 0.5% of the design requirement range, the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 2 points; if they are lower than 0.5% to 1% of the design requirement range, the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 1 point; if they are lower than 1% of the design requirement range, the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 0 points, and the cuttings logging score, drilling logging score and while drilling gamma value score are obtained; the cuttings logging score, drilling logging score and while drilling gamma value score are weighted summed to obtain the logging score.

[0022] Preferably, the evaluation of the drilling project according to the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score includes:

[0023] The weights of the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score are determined using the independence weight coefficient method, and the weighted sum of the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score is taken to obtain the comprehensive score of the drilling project; the comprehensive score of the drilling project is used to evaluate the drilling project.

[0024] Preferably, the grouting quality of each grouting hole is evaluated according to the grouting end pressure, the grouting end pump volume, the slurry injection volume and the rock and soil permeability, including:

[0025] The grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole are evaluated respectively. In response to the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole being qualified, the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability are normalized; based on the normalized grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole, the corresponding weights are obtained using the entropy weight method; according to the normalized grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole and the corresponding weights, the comprehensive score of each grouting hole is obtained based on the TOPSIS algorithm; and the grouting quality of each grouting hole is evaluated based on the comprehensive score of each grouting hole.

[0026] Preferably, the evaluation of the surrounding rock reinforcement effect of the fault management area by using geophysical detection results, water inflow and core sampling rate includes:

[0027] Based on the geophysical detection results, the surrounding rock evaluation grades of the grouting reinforcement section are evaluated. The surrounding rock evaluation grades of the grouting reinforcement section are water-rich, partially water-containing, less water and no water. The surrounding rock reinforcement effect of the fault treatment area is evaluated according to the surrounding rock evaluation grades of the grouting reinforcement section.

[0028] Construction inspection holes are used to obtain the proportion of water inflow after grouting treatment that is less than the preset water inflow, and the surrounding rock reinforcement effect of the fault treatment area is evaluated based on the proportion of water inflow after grouting treatment that is less than the preset water inflow;

[0029] Obtain the core sampling rate and evaluate the surrounding rock reinforcement effect in the fault management area based on the core sampling rate.

[0030] The embodiments of the present invention have at least the following beneficial effects: The present invention conducts a progressive and comprehensive analysis from three aspects: drilling construction control, grouting process management, and post-evaluation of treatment effect for the reinforcement of surrounding rock of fault fracture zone tunnels. Under the condition that there are problems with the quality of the drilling project, even if the quality of the grouting project is qualified, the expected treatment effect cannot be achieved. Therefore, the present invention first evaluates and controls the quality of the drilling construction to ensure that the boreholes in the grouting stage are of qualified quality, thereby avoiding the loss of personnel and extension of the treatment period caused by unqualified boreholes entering the grouting stage. At the same time, the process management of the quality of the grouting project in the second stage is carried out to greatly improve the quality of the grouting project. The boreholes with poor grouting quality will no longer enter the post-evaluation stage of the treatment effect, thereby reducing the evaluation workload. At the same time, remedial measures can be taken immediately after the quality of the grouting project is grasped at the first time, without having to wait until the effect verification in the final stage is unqualified before remediation, thereby maximizing the use of project time;

[0031] In the post-evaluation stage of the treatment effect, comprehensive geophysical exploration was used as a guide for preliminary verification, and drilling was used to conduct secondary verification of the local low-resistance abnormal area, reducing the amount of drilling engineering. In combination with geophysical exploration and drilling, the scope of the low-resistance abnormal area was determined, and the treatment effect of the fault area was comprehensively and quantitatively evaluated in conjunction with the water inflow of the inspection hole and the core sampling rate, overcoming the uncertainty of the previous subjective factor evaluation. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. 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 creative work.

[0033] Figure 1 A method flow chart of a method for evaluating the effect of exploration and injection in a surrounding rock reinforcement project of a fault fracture zone roadway provided by an embodiment of the present invention;

[0034] Figure 2 An engineering schematic diagram of a method for evaluating the effect of exploration and injection in a surrounding rock reinforcement project of a fault fracture zone tunnel provided by an embodiment of the present invention.

[0035] Among them, 1 represents one opening, 2 represents two openings, 3 represents three openings, 4 represents tunnel, and 5 represents fault. DETAILED DESCRIPTION

[0036] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel proposed by the present invention, in combination with the accompanying drawings and preferred embodiments, as well as its specific implementation method, structure, features and effects. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0037] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0038] The specific scheme of the method for evaluating the effect of exploration and injection in the surrounding rock reinforcement engineering of a fault fracture zone roadway provided by the present invention is described in detail below with reference to the accompanying drawings.

[0039] Example:

[0040] The main application scenarios of the present invention are: in the construction of mine shafts and tunnels, fault fracture zones are common geological structures, which pose a serious threat to the stability of the surrounding rock. In order to ensure the safe progress of the project, it is often necessary to carry out grouting reinforcement treatment on the fault fracture zone. However, the effect of grouting reinforcement is directly related to the stability and safety of the project. Therefore, how to scientifically and accurately evaluate the effect of grouting reinforcement has become an urgent problem to be solved in the engineering community. The present invention conducts a quantitative evaluation of the surrounding rock reinforcement project of fault tunnels from three aspects: drilling construction control, grouting process management evaluation, and regional governance effect.

[0041] See also Figure 1 , which shows a method flow chart of a method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone roadway provided by an embodiment of the present invention, the method comprising the following steps:

[0042] Step S1, obtaining the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score of the drilling project in the fault management area; and evaluating the drilling project according to the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score.

[0043] The present invention proposes a full-process evaluation method for the exploration and injection effect of the surrounding rock reinforcement project of the fault fracture zone tunnel. Each evaluation link is closely connected with each other, and the evaluation result can more accurately reflect the engineering quality and treatment effect.

[0044] First of all, it is necessary to determine the fault management area, and use the comprehensive geophysical exploration, drilling and working face design on the ground and underground to delineate the affected area of ​​the fault fracture zone as the regional management range, that is, the fault management area. Furthermore, a drilling platform is deployed on the ground to construct horizontal multi-branch directional drilling from the ground.

[0045] In the embodiment of the present invention, a three-opening hole-forming structure is adopted. The first and second openings use smooth, crack-free, and thread-intact J55 steel-grade oil casing. The vertical section from the ground to the bottom is a one-opening structure (Φ311.2 mm), the inclination section is a two-opening structure (Φ215.9 mm), and the horizontal section after the borehole enters the target treatment layer is a three-opening structure (Φ152.4 mm). The borehole is protected by steel casing at the first and second opening positions, wherein the three-opening includes multiple branch holes, such as Figure 2 The drilling structure is shown in Table 1:

[0046] Table 1 Drilling structure

[0047]

[0048] As one of the drilling engineering indicators, the quality of the solid pipe needs to be evaluated to obtain the solid pipe quality score. The pressure test is used to check the quality of the solid pipes of the single-opening and double-opening casings, and the pressure drop rate is used to evaluate the quality of the solid pipes. After the solid pipe is solidified for 48 hours, a pressure test is carried out on the single-opening casing. The pressure is 4.0MPa and observed for 0.5h. The pressure drop is less than 0.5MPa, and the solid pipe quality is qualified. A pressure test is carried out on the double-opening casing. The pressure is 10.0MPa and observed for 0.5h. The pressure drop rate is less than 0.5MPa, and the solid pipe quality is qualified. It should be noted that the construction process of the present invention is that after a branch hole of the single-opening, double-opening and triple-opening is drilled, it is necessary to conduct a drilling quality evaluation, and then grouting is carried out after it is qualified.

[0049] Specifically, the pressure drop rate of the solid pipe quality evaluation index is scored to obtain the solid pipe quality score A1. When the pressure drop rate is greater than the first threshold, the solid pipe quality score is 0 points; the pressure drop rate is within the first range, recorded as 1 point, the pressure drop rate is within the second range, recorded as 2 points, and the pressure drop rate is less than or equal to the second threshold, recorded as 3 points. Among them, the first threshold, the first range, the second range, and the second threshold are 0.5MPa / 0.5h, 0.3-0.5MPa / 0.5h, 0.1-0.3MPa / 0.5h, and 0.1MPa / 0.5h, respectively. The solid pipe quality score A1 is obtained.

[0050] Reasonable control of mud parameters can ensure that the slurry in the hole has strong cuttings carrying capacity and lubrication performance, while preventing crack blockage from affecting the subsequent grouting effect. During drilling, relevant instruments are used to dynamically monitor the mud performance parameters used. Mud performance parameters include mud viscosity, mud density and mud pH.

[0051] The design range values ​​of the secondary indicators mud viscosity, mud density and mud pH are obtained, and scores are given according to the design range values. Within the design range values, the scores of mud viscosity, mud density and mud pH are recorded as 3 points; if they exceed or fall below the design range values ​​by 5%, the scores of mud viscosity, mud density and mud pH are recorded as 2 points; if they exceed or fall below the design range values ​​by 5% to 10%, the scores of mud viscosity, mud density and mud pH are recorded as 1 point; if they exceed or fall below the design range values ​​by 10%, the scores of mud viscosity, mud density and mud pH are recorded as 0 points.

[0052] Thus, the scores of standard mud viscosity, mud density and mud pH can be obtained, which are recorded as A21, A22 and A23 respectively. The weighted sum of the scores of standard mud viscosity, mud density and mud pH is obtained to obtain the mud performance parameter score A2, where the weights of the scores of standard mud viscosity, mud density and mud pH are 0.4, 0.4 and 0.2 respectively. The implementer can adjust according to the actual situation. The calculation formula is A2 = A21 × 0.4 + A22 × 0.4 + A23 × 0.2. When the mud performance parameter score is less than 1 point, it is evaluated as unqualified; the mud performance parameter score is 1 to 2 points, which is evaluated as qualified; the mud performance parameter score is 2 to 3 points, which is evaluated as good; the index score is 3 points, which is evaluated as excellent.

[0053] During the drilling process, attention should also be paid to the actual depth of the borehole. After the exploration construction is completed, the actual depth of the borehole is determined based on the length of the drill bit in the hole. In principle, the actual depth of the borehole should not be less than the designed depth, and the distance the borehole passes through the fault should not be less than the width of the water-proof coal (rock) pillar of the water-bearing or water-conducting fault. If unfavorable geological structures are encountered and construction cannot be carried out to the expected position, it is necessary to grout the formation and then redirect the drilling or add additional holes to fill the blank areas to achieve full coverage of the treatment area. The retention of water-proof coal (rock) pillars for water-bearing or water-conducting faults can be calculated according to the following empirical formula:

[0054]

[0055] In the formula, L is the width of the coal pillar, m; K is the safety factor, generally 2 to 5; M is the thickness of the coal seam or the mining height, m; p is the actual water head value, MPa; Kp is the tensile strength of coal, MPa.

[0056] The actual hole depth is determined based on the length of the drill bit in the hole after the construction is completed, and then an evaluation is carried out.

[0057] Specifically, when the actual borehole depth on both sides of the fault exceeds the maximum width of the water-bearing or water-conducting fault water-isolating coal (rock) pillar, the borehole depth score A3 is recorded as 3 points, which is evaluated as excellent.

[0058] When the actual borehole depth on one side of the fault exceeds the maximum width of the water-bearing or water-conducting fault water-isolating coal (rock) pillar, the borehole depth score A3 is recorded as 2 points, which is evaluated as good.

[0059] When the actual borehole depth on both sides of the fault exceeds the minimum width of the water-bearing or water-conducting fault water-isolating coal (rock) pillar, the borehole depth score A3 is recorded as 1 point and is assessed as qualified.

[0060] When the actual borehole depth on both sides of the fault does not exceed the minimum width of the water-bearing or water-conducting fault waterproof coal (rock) pillar, the borehole depth score A3 is recorded as 0 points and is evaluated as unqualified.

[0061] The actual borehole depth is compared with the designed hole depth to ensure that the final borehole of the drilling construction exceeds the water-bearing or water-conducting fault waterproof coal (rock) pillar, and the regional governance scope is fully covered without blind spots.

[0062] The horizontal section of the branch hole uses a wireless measurement while drilling system to monitor the drilling trajectory (x, y, z), and the deviation of the actual trajectory from the designed trajectory shall not exceed 2m. Each branch hole should be evenly distributed outside the roadway contour at the intersection with the fault to ensure that the slurry diffusion radius forms a grouting intersection circle within the plastic circle of the roadway. The range of the plastic circle, that is, the range of the roadway surrounding rock reinforcement, can be calculated based on the limit equilibrium theory:

[0063]

[0064] Where: R is the radius of the plastic zone, r1 is the radius of the roadway, γ is the average bulk density of the formation, C is the cohesion of the surrounding rock, is the internal friction angle.

[0065] Specifically, the drilling trajectory is scored. Under the premise of ensuring that the grouting intersection circle is formed within the plastic zone of the tunnel, if the deviation of the actual drilling trajectory of the horizontal branch hole compared with the designed trajectory is within the first deviation range, the drilling trajectory score A4 is recorded as 3 points, which is evaluated as excellent; if the deviation is within the second deviation range compared with the designed trajectory, the drilling trajectory score A4 is recorded as 2 points, which is evaluated as good; if the deviation is within the third deviation range compared with the designed trajectory, the drilling trajectory score A4 is recorded as 1 point, which is evaluated as qualified; if the slurry diffusion radius fails to form a grouting intersection circle within the plastic zone of the tunnel or the deviation from the designed trajectory is above the maximum deviation, the drilling trajectory score A4 is recorded as 0 points, which is evaluated as unqualified. The first deviation range, the second deviation range, the third deviation range and the maximum deviation are 0-0.5m, 0.5-1.5m, 1.5-2.0m and 2m, respectively.

[0066] The drilling quality is evaluated based on logging technology. Specifically, logging indicators include three secondary indicators. Based on cuttings logging, logging while drilling and gamma value data while drilling, the sequence and lithology of the underground strata can be mastered through cuttings logging. The bedrock section of the main hole is recorded once every 10m, and the drilling density is gradually increased near the marker layer. The horizontal branch hole section is recorded every 1m until the end of the hole. The logging while drilling is recorded once every 10m from the bedrock section to the completion of the well. The sudden change point during drilling should be recorded at any time to timely discover the starting and ending depths of coal seams, karst caves, fault fracture zones, etc.

[0067] Among them, the secondary indicators include cuttings logging, drilling logging and gamma while drilling, which are scored according to the corresponding design requirements. If the score is lower than 0.5% of the design requirements, the secondary indicator score is recorded as 2 points; if it is lower than 0.5% to 1% of the design requirements, the secondary indicator score is recorded as 1 point; if it is lower than 1% of the design requirements, the secondary indicator score is recorded as 0 points. Thus, the cuttings logging score A51, the drilling logging score A52 and the drilling gamma value score A53 can be obtained; then the logging score needs to be obtained by the weighted sum of the scores of cuttings logging, drilling logging and gamma while drilling, and the weights of the three are 0.4, 0.3 and 0.3 respectively, and the calculation formula is A5 = A51 × 0.4 + A52 × 0.3 + A53 × 0.3. When the logging index score is lower than 1 point, it is evaluated as unqualified; the index score is 1 to 2 points, it is evaluated as qualified; the index score is 2 to 3 points, it is evaluated as good; the index score is 3 points, it is evaluated as excellent.

[0068] Furthermore, the drilling project is comprehensively evaluated based on the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score. Specifically, the weights of the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score are determined by the independence weight coefficient method. Let A = {A1, A2, A3, A4, A5} = {X1, X2, X3, X4, X5}, and let Ri be the complex correlation coefficient between Xi and other indicators. The complex correlation coefficient R1 between the score X1 and the scores of other indicators is also the goodness of fit of the multivariate regression of the score X1 and the scores of other indicators. Therefore, when calculating the complex correlation coefficient Ri, it can be solved by regression. Weight each score, find the inverse of the complex correlation coefficient 1 / Ri between each indicator score and other indicator scores, and normalize the obtained set of 1 / Ri data to obtain the weight of each indicator score. The weighted sum of each indicator weight and the corresponding indicator score is obtained to obtain the comprehensive score of the drilling project. If any of the five evaluation indicators is unqualified, the drilling project quality will be evaluated as unqualified; if the comprehensive evaluation score of the drilling project is 1-2 points, it will be evaluated as qualified; if the score is 2-3 points, it will be evaluated as good; if the score is 3 points, it will be evaluated as excellent. If the comprehensive evaluation of the drilling project quality is unqualified, re-drilling is required until the drilling project quality is qualified.

[0069] Step S2, after the drilling project is qualified, grouting is carried out, and the grouting quality of each grouting hole is evaluated according to the grouting end pressure, grouting end pump volume, slurry injection volume and rock and soil permeability.

[0070] In step S1, it is described that the drilling structure is divided into one opening, two openings and three openings, wherein the three openings are bare holes, which are drilled along the direction of tunnel excavation, with the purpose of grouting reinforcement of the tunnel surrounding rock. The three openings have multiple branch holes for grouting, and each branch hole is recorded as a grouting hole. The number of grouting holes needs to be set according to the actual needs of grouting reinforcement, and the number is recorded as I in the present invention.

[0071] After the drilling project is qualified, the grouting project begins. During the grouting project, the grouting quality also needs to be evaluated. The grouting quality is evaluated based on the grouting end pressure, grouting end pump volume, slurry injection volume and rock and soil permeability. Specifically, the grouting pressure data during the grouting period is collected through the pressure gauge installed on the high-pressure grouting equipment to evaluate the grouting end pressure.

[0072] Taking the hydrostatic pressure of the grouting section as the reference standard, if the pressure at the end of grouting is less than 1.5 times the hydrostatic pressure of the grouting section, it is unqualified, 1.5 to 2.0 times is qualified, 2.0 to 2.5 times is good, and more than 2.5 times is excellent.

[0073] Before the end of grouting, observe the changes in the grouting flowmeter, determine the pump volume at the end of grouting, and compare it with the design value of 60L / min at the end of grouting. If the grouting flow before the end of grouting is greater than the design value, the single indicator is evaluated as unqualified. When the pump volume at the end of grouting is lower than the design value, the single indicator is evaluated as qualified or above.

[0074] Slurry injection volume: Use the flow meter on the grouting equipment to determine the total grouting volume (cement, sawdust, etc.) injected into the hole. According to the Grouting Construction Manual, the effective diffusion radius of the slurry should be 8 to 12 meters, and the theoretical grouting volume is calculated in combination with the average fracture rate of the injected formation. If the actual slurry injection volume is less than the theoretical value, the single indicator is evaluated as unqualified. When the actual slurry injection volume is greater than the theoretical value, the single indicator is evaluated as qualified or above. The calculation method of the theoretical grouting volume is:

[0075]

[0076] Among them, Q is the slurry injection volume; A is the slurry consumption coefficient, which is 1.2 to 1.5; R is the effective diffusion distance of the slurry; r is the radius of the grouting hole arrangement circle; H is the grouting section height; n is the average fracture rate of the rock formation, which is 0.5 to 5%; B is the slurry filling coefficient, which is 0.9 to 0.95; m is the slurry solidification rate, which is 0.85.

[0077] A water pressure test is carried out before and after grouting to determine the water permeability of the rock mass, the unit of which is Lu, and the rock mass permeability grade is extremely slightly permeable as the evaluation standard. If the water permeability of the rock mass is greater than 0.1Lu after the grouting, the single index is evaluated as unqualified. After the grouting, the water permeability of the rock mass is less than 0.1Lu, and the single index is evaluated as qualified or above. The water permeability q of the test section is calculated according to the following formula:

[0078]

[0079] Where: q s is the water permeability of the test section, that is, the permeability of the rock and soil, in Lu; Q s is the stable flow rate of the test section, in L / min; L s is the length of the test section, in m; P s is the test section pressure, in MPa.

[0080] Furthermore, the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole are obtained for judgment. When the indicators of each grouting hole are initially judged to be qualified, the grouting quality of the grouting hole is evaluated using the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of the grouting hole. If one of the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of the grouting hole is unqualified, the grouting project quality evaluation is unqualified. Specifically, the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of all grouting holes are obtained. Due to the different unit dimensions of the grouting project quality evaluation indicators, the four indicators of grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability are dimensionlessly normalized. Among the four indicators, there are positive indicators and negative indicators, so they are normalized separately. The normalization formula for the positive indicator is: The normalization formula for negative indicators is: Among them, x ij represents the jth normalized index of the i-th grouting hole, k ij The jth index of the i-th grouting hole (not normalized).

[0081] The entropy weight method is further used to calculate the information entropy E of each indicator. j , characteristic difference index D j and entropy weight ω j Information entropy E j Calculated by the following formula: in is the weight of each indicator; characteristic difference index D j =1-E j ; Entropy weight Entropy weight ω jThat is, the objective weight of the jth evaluation index for each grouting hole, ω j ∈[0,1], J is the number of evaluation indicators, which is 4 in the present invention, and I is the number of grouting holes.

[0082] Furthermore, the TOPSIS algorithm is used to obtain the optimal value of each indicator. and the worst value Calculate the index and and When calculating the Euclidean distance, it is combined with the weight value ω determined based on the entropy weight method. j To couple, that is: in, and It represents the optimal Euclidean distance and the worst Euclidean distance corresponding to the i-th grouting hole, and then obtains the comprehensive score of the i-th grouting hole.

[0083] For each grouting hole, if one of the corresponding indicators among the grouting end pressure, grouting end pump volume, slurry injection volume and rock and soil permeability is unqualified, the grouting quality is judged to be unqualified. If all its indicators are qualified, its comprehensive score S i ∈(0, 0.5] is considered as qualified grouting quality, S i ∈(0.5, 0.8] grouting quality is good, S i ∈(0.8, 1] the grouting quality is excellent. Thus the grouting quality evaluation of the grouting hole is completed.

[0084] Step S3, after the grouting quality of all grouting holes is evaluated as qualified, the surrounding rock reinforcement effect of the fault treatment area is evaluated using the geophysical detection results, water inflow and core sampling rate.

[0085] After grouting in the target fault treatment area, the fault treatment area where the drilling engineering treatment and grouting engineering quality are assessed as qualified or above is verified and evaluated, and the tunnel surrounding rock reinforcement effect is evaluated. The specific steps are as follows:

[0086] According to the geological characteristics of the fault fracture zone, the grouting reinforcement body is geophysically detected by geological radar and transient electromagnetic method, and the changes of the physical field of the surrounding rock in front are detected by geophysical instruments. The reinforcement effect of the surrounding rock in front is inferred by analyzing and studying the geophysical data obtained. At the same time, it is also necessary to construct inspection holes in the tunnel. The changes in the location and amount of water inflow during the drilling process can be used to infer the location changes of the water-rich area, and the proportion of water inflow after grouting treatment that is less than the preset water inflow can be calculated. b , R b =1-actual water inflow / preset water inflow / inspection hole length, where the preset water inflow is 0.2L / min; further, coring is performed on the inspection hole, and the core sampling rate S is calculated.y .

[0087] Next, according to the geophysical detection results and the proportion of water inflow less than the preset water inflow, R b and core recovery rate S y The surrounding rock reinforcement effect in the fault management area is evaluated.

[0088] Specifically, by analyzing the geophysical detection results, the evaluation level of the surrounding rock in the grouting reinforcement section is rich in water, and the surrounding rock reinforcement effect in the fault treatment area is evaluated as unqualified; the evaluation level is partially water-containing, and the surrounding rock reinforcement effect in the fault treatment area is evaluated as qualified; the evaluation level is less water, and the surrounding rock reinforcement effect in the fault treatment area is evaluated as good; the evaluation level is no water, and the surrounding rock reinforcement effect in the fault treatment area is evaluated as excellent;

[0089] The proportion of water inflow less than the preset water inflow R b If the water inflow is less than 70%, the surrounding rock reinforcement effect in the fault control area is evaluated as unqualified; if the water inflow is less than the proportion of the preset water inflow R b If the water inflow is less than the proportion of the preset water inflow R b If the water inflow is less than 80% or equal to 80% and less than 90%, the surrounding rock reinforcement effect in the fault control area is evaluated as good; if the water inflow is less than the proportion of the preset water inflow R b If it is greater than or equal to 90% and less than or equal to 100%, the surrounding rock reinforcement effect in the fault treatment area is evaluated as excellent;

[0090] Core recovery rate S y <50%, the surrounding rock reinforcement effect in the fault control area is evaluated as unqualified; the core sampling rate is 50%≤S y <75%, the surrounding rock reinforcement effect in the fault control area is evaluated as qualified; the core sampling rate is 75%≤S y <90%, the surrounding rock reinforcement effect in the fault control area is evaluated as good; the core sampling rate is 90%≤S y ≤100%, the surrounding rock reinforcement effect in the fault management area is evaluated as excellent.

[0091] When the surrounding rock evaluation grade of the grouting reinforcement section, the proportion of water inflow less than the preset water inflow and the core sampling rate are all qualified, it means that the surrounding rock reinforcement effect of the fault management area is qualified. Among them, the surrounding rock evaluation grade of the grouting reinforcement section, the proportion of water inflow less than the preset water inflow and the core sampling rate are all qualified / good / excellent, which means that the surrounding rock reinforcement effect of the fault management area is qualified / good / excellent. When the three indicators are evaluated as qualified, good and good, the overall evaluation is qualified. When two are qualified and one is good, it is also qualified. That is, when the results of the three indicator evaluations are inconsistent, the lowest evaluation result is taken as the final evaluation result.

[0092] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The above is a description of a specific embodiment of this specification. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0093] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in fault fracture zone tunnels, characterized in that: The method includes: Obtaining the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and mud logging score of the drilling project in the fault management area; evaluating the drilling project based on the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and mud logging score; After the drilling project is qualified, grouting is carried out, and the grouting quality of each grouting hole is evaluated according to the grouting end pressure, grouting end pump volume, slurry injection volume and rock and soil permeability; After the grouting quality of all grouting holes is evaluated as qualified, the surrounding rock reinforcement effect of the fault control area is evaluated using geophysical detection results, water inflow and core sampling rate.

2. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel according to claim 1 is characterized in that: The solid pipe quality score includes: Obtain the solid pipe quality score. When the pressure drop rate is greater than the first threshold, the solid pipe quality score is 0 points; when the pressure drop rate is within the first range, it is recorded as 1 point; when the pressure drop rate is within the second range, it is recorded as 2 points; when the pressure drop rate is less than or equal to the second threshold, it is recorded as 3 points.

3. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone roadway according to claim 1 is characterized in that: The mud performance parameter score includes: The mud performance parameters include mud viscosity, mud density and mud pH, and the design range values ​​of mud viscosity, mud density and mud pH are obtained; within the design range values, the scores of mud viscosity, mud density and mud pH are recorded as 3 points; if they exceed or fall below the design range values ​​by 5%, the scores of mud viscosity, mud density and mud pH are recorded as 2 points; if they exceed or fall below the design range values ​​by 5% to 10%, the scores of mud viscosity, mud density and mud pH are recorded as 1 point; if they exceed or fall below the design range values ​​by 10%, the scores of mud viscosity, mud density and mud pH are recorded as 0 points; the weighted sum of the scores of mud viscosity, mud density and mud pH is obtained to obtain the mud performance parameter score.

4. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel according to claim 1 is characterized in that: The drilling depth score includes: When the actual borehole depth on both sides of the fault exceeds the maximum width of the water-bearing or water-conducting fault water-blocking coal (rock) pillar, the borehole depth score is recorded as 3 points, which is rated as excellent; When the actual borehole depth exceeds the maximum width of the water-bearing or water-conducting fault water-blocking coal (rock) pillar on one side of the fault, the borehole depth score is recorded as 2 points, which is rated as good; When the actual borehole depth on both sides of the fault exceeds the minimum width of the water-bearing or water-conducting fault water-blocking coal (rock) pillar, the borehole depth score is recorded as 1 point and is evaluated as qualified; When the actual borehole depth on both sides of the fault does not exceed the minimum width of the water-bearing or water-conducting fault waterproof coal (rock) pillar, the borehole depth score is recorded as 0 points and is assessed as unqualified.

5. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel according to claim 1, characterized in that: The drilling trajectory score includes: If the deviation of the actual drilling trajectory of the horizontal branch hole compared with the designed trajectory is within the first deviation range, the drilling trajectory score is recorded as 3 points, which is evaluated as excellent; if the deviation is within the second deviation range compared with the designed trajectory, the drilling trajectory score is recorded as 2 points, which is evaluated as good; if the deviation is within the third deviation range compared with the designed trajectory, the drilling trajectory score is recorded as 1 point, which is evaluated as qualified; if the slurry diffusion radius fails to form a grouting circle within the plastic zone of the tunnel or the deviation from the designed trajectory is above the maximum deviation, the drilling trajectory score is recorded as 0 point, which is evaluated as unqualified.

6. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone roadway according to claim 1, characterized in that: The mud logging score includes: The logging includes cuttings logging, drilling logging and while drilling gamma value, which are scored according to the design requirement range corresponding to each logging; if the logging includes cuttings logging, drilling logging and while drilling gamma value, they are all within the design range, and the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 3 points; if they are lower than 0.5% of the design requirement range, the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 2 points; if they are lower than 0.5% to 1% of the design requirement range, the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 1 point; if they are lower than 1% of the design requirement range, the scores of cuttings logging, drilling logging and while drilling gamma value are recorded as 0 points, and the cuttings logging score, drilling logging score and while drilling gamma value score are obtained; the cuttings logging score, drilling logging score and while drilling gamma value score are weighted summed to obtain the logging score.

7. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel according to claim 1, characterized in that: The drilling project is evaluated based on the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score, including: The weights of the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score are determined using the independence weight coefficient method, and the weighted sum of the solid pipe quality score, mud performance parameter score, borehole depth score, borehole trajectory score and logging score is taken to obtain the comprehensive score of the drilling project; the comprehensive score of the drilling project is used to evaluate the drilling project.

8. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone tunnel according to claim 1, characterized in that: The grouting quality of each grouting hole is evaluated according to the grouting end pressure, grouting end pump volume, slurry injection volume and rock and soil permeability, including: The grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole are evaluated respectively. In response to the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole being qualified, the grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability are normalized; based on the normalized grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole, the corresponding weights are obtained using the entropy weight method; according to the normalized grouting end pressure, grouting end pump volume, slurry injection volume and rock-soil permeability of each grouting hole and the corresponding weights, the comprehensive score of each grouting hole is obtained based on the TOPSIS algorithm; and the grouting quality of each grouting hole is evaluated based on the comprehensive score of each grouting hole.

9. The method for evaluating the effect of exploration and injection of surrounding rock reinforcement engineering in a fault fracture zone roadway according to claim 1, characterized in that: The evaluation of the surrounding rock reinforcement effect of the fault management area by using geophysical detection results, water inflow and core sampling rate includes: Based on the geophysical detection results, the surrounding rock evaluation grades of the grouting reinforcement section are evaluated. The surrounding rock evaluation grades of the grouting reinforcement section are water-rich, partially water-containing, less water and no water. The surrounding rock reinforcement effect of the fault treatment area is evaluated according to the surrounding rock evaluation grades of the grouting reinforcement section. Construction inspection holes are used to obtain the proportion of water inflow after grouting treatment that is less than the preset water inflow, and the surrounding rock reinforcement effect of the fault treatment area is evaluated based on the proportion of water inflow after grouting treatment that is less than the preset water inflow; Obtain the core sampling rate and evaluate the surrounding rock reinforcement effect in the fault management area based on the core sampling rate.

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