Rock mass quality classification method based on tunnel boring machine working conditions

Abstract

The present invention discloses a rock mass quality classification method based on the working condition of a tunnel boring machine, comprising the following steps: (1) determining the minimum rock mass quality evaluation unit; (2) obtaining the tunnel boring machine working condition corresponding to each minimum measurement evaluation unit; (3) calculating the tunnel boring machine advance rate of each minimum measurement evaluation unit, and establishing a tunnel boring machine working condition record database; (4) obtaining the rock mass quality classification result of each minimum measurement evaluation unit based on the rock mass quality classification standard; (5) establishing a rock mass quality classification database, and recording the rock mass quality classification index, rock mass quality classification result and tunnel boring machine advance rate of each minimum measurement evaluation unit in the rock mass quality classification database; (6) based on the rock mass quality classification database, performing real-time rating and classification of rock mass quality according to the tunnel boring machine advance rate. The rock mass quality classification method based on the working condition of the tunnel boring machine of the present invention can perform real-time evaluation and classification of rock mass quality.

Description

Technical Field

[0001] The present invention relates to rock mass quality evaluation in mining engineering and underground rock engineering, and in particular to a rock mass quality classification method based on the working conditions of a tunnel boring machine. Background Art

[0002] During the construction and mining of underground metal mines, the quality of rock mass is an important basis and prerequisite for evaluating the engineering properties and stability of rock mass.

[0003] The most commonly used rock mass classification method in China is the Rock Mass Rating (RMR) method. In the Rock Mass Rating (RMR) method, various mechanical indicators of drill cores need to be obtained as the basic basis for rock mass quality classification. The information on the occurrence of joints and fissures in the rock mass is one of the important indicators for evaluating rock mass quality classification.

[0004] However, core displacement often occurs during the coring and core placement process, and the true information on the occurrence of surrounding rock joints and fissures cannot be obtained. Therefore, a more scientific and effective method is needed to measure and count the joints and fissures of the rock mass. At present, the domestic evaluation of rock mass quality in underground metal mines is often based on the on-site joint and fissure investigation results of a typical middle section of a tunnel or mining area. Investigators need to spend a lot of time and energy to carry out a lot of field work. However, the investigation results often have limitations and can only reflect the rock mass quality evaluation results of local areas. During the construction and mining of underground metal mines, a large number of geological drilling holes need to be constructed to achieve the results of prospecting and geological surveys.

[0005] In view of the above problems, the present invention provides a rock mass quality classification method based on the working conditions of a tunnel boring machine. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a rock quality grading method based on the working conditions of a tunnel boring machine. The rock quality grading method can obtain the working conditions of the tunnel boring machine during the tunneling process, and identify and count the rock joint and fissure information, thereby reducing the time for workers to conduct on-site investigations and measurements, and can judge the rock quality grading results in real time during the tunneling process.

[0007] In order to solve the above technical problems, the present invention provides a rock mass quality classification method based on the working conditions of a tunnel boring machine, comprising the following steps:

[0008] (1) Determine the minimum rock mass quality evaluation unit and divide the entire rock mass length range into several minimum measurement evaluation units;

[0009] (2) obtaining the working condition of the tunnel boring machine corresponding to each of the minimum measurement and evaluation units, wherein the working condition of the tunnel boring machine includes the power, rotation speed, degree of drill bit wear, tunneling speed, and degree of ore and rock crushing of the tunnel boring machine during the tunneling process;

[0010] (3) calculating the tunneling rate of the tunnel boring machine for each minimum measurement and evaluation unit, and establishing a tunnel boring machine working condition record database;

[0011] (4) setting a minimum measurement and evaluation unit, scoring and summing the rock mass quality classification indicators of each minimum measurement and evaluation unit based on the rock mass quality classification standard, and obtaining the rock mass quality classification result of each minimum measurement and evaluation unit;

[0012] (5) establishing a rock mass quality classification database, and recording the rock mass quality classification index, the rock mass quality classification result, and the tunneling rate of the tunnel boring machine of each minimum measurement and evaluation unit in the rock mass quality classification database;

[0013] (6) Based on the rock mass quality classification database, the rock mass quality is rated and classified in real time according to the tunneling speed of the tunnel boring machine.

[0014] Preferably, the rock mass quality classification method based on the working conditions of the tunnel boring machine according to claim 1 is characterized in that the minimum measurement and evaluation unit length is 3m within the footage length of one operation cycle.

[0015] Specifically, the rock mass quality classification index includes an intact rock strength index, a rock quality index, a rock mass joint spacing index, a rock mass joint state index and a groundwater state index.

[0016] Furthermore, in the minimum measurement and evaluation unit, rock fragments after the tunnel boring machine breaks the rock are sampled and subjected to an irregular rock point load test, the point load strength is corrected, and a corrected point load strength index is calculated. The point load strength correction method is as follows:

[0017] a. Uncorrected point load strength index calculation

[0018]

[0019]

[0020] Where Is is the point load strength index before correction, P is the load when the specimen fails, De is the equivalent diameter of the specimen, W is the average width of the minimum cross section passing through the two loading points, and D is the distance between the loading points;

[0021] b. Point load strength index correction

[0022] I s50 =f×I s

[0023] f=(D e / 50) m

[0024] Among them I s50 is the corrected point load strength index, f is the correction factor, and m is the correction factor index.

[0025] Furthermore, based on the downhole geological exploration drilling core data, the actual length of the core greater than or equal to 10 cm in a single hole is measured and summed up, and the calculation formula is as follows:

[0026]

[0027] Furthermore, the number of joints and fissures in a single borehole is statistically recorded based on the borehole image of the single borehole, the total number of joints and fissures in the rock mass through which the borehole passes within the depth range of the single borehole is obtained, and the rock mass joint spacing index is calculated:

[0028] The joint spacing index is equal to the drilling depth of a single borehole / the total number of joints and fissures in the rock mass passed by the borehole within the range of the single borehole depth.

[0029] Furthermore, the state of the joint surface in the minimum measurement and evaluation unit is investigated and recorded, the corrosion and roughness of the joint surface are observed, and the rock joint state index in the minimum measurement and evaluation unit is judged based on the roughness, corrosion and closure degree of the joint surface.

[0030] Furthermore, the water flow rate and duration of the rock mass within the minimum measurement and evaluation unit are obtained, and the groundwater status index of the rock mass is determined based on the water flow rate and duration.

[0031] Furthermore, the tunneling rate of the tunnel boring machine within the minimum measurement and evaluation unit is counted, and the time required for the tunnel boring machine to complete the tunneling work within a single minimum measurement and evaluation unit under normal working conditions is obtained. The tunneling rate of the tunnel boring machine is calculated, and the wear of the tunnel boring machine drill bit is observed. The tunneling rate calculation method of the tunnel boring machine is as follows:

[0032]

[0033] Specifically, the tunneling rate is calculated during the tunneling process of the tunnel boring machine, and the corresponding rock mass quality classification result is obtained based on the rock mass classification database established in step 5.

[0034] Through the above technical solution, the beneficial effects of the present invention are as follows:

[0035] The rock mass quality grading method based on the working condition of the tunnel boring machine of the present invention scores and grades the rock mass within the minimum measurement and evaluation unit based on data such as underground prospecting geological drilling cores, rock strength characteristics after tunnel boring machine rock breaking, face joint and fissure characteristics, and groundwater status, and matches the data with the tunneling rate of the tunnel boring machine in real time, thereby establishing a rock mass quality grading database. The real-time evaluation and grading of rock mass quality improves the accuracy and timeliness of rock mass quality grading in underground metal mines, thereby ensuring the safety of underground personnel and equipment and reducing support costs.

[0036] Other advantages of the present invention and the technical effects of the preferred embodiments will be further described in the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a flow chart of the rock mass quality classification method based on the working condition of the tunnel boring machine in the present invention;

[0038] Figure 2 This is a flow chart of obtaining rock mass quality classification results of the rock mass quality classification method based on the working condition of the tunnel boring machine in the present invention;

[0039] Figure 3 It is a schematic diagram of the point load strength test and equivalent diameter calculation of the rock mass quality classification method based on the working condition of the tunnel boring machine in the present invention. DETAILED DESCRIPTION

[0040] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0041] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] like Figure 1 As shown in FIG. 1 , as an embodiment of the rock mass quality classification method based on the working condition of the tunnel boring machine provided by the present invention, the method includes the following steps:

[0043] (1) Determine the minimum rock mass quality evaluation unit and divide the entire rock mass length range into several minimum measurement evaluation units;

[0044] (2) obtaining the working condition of the tunnel boring machine corresponding to each of the minimum measurement and evaluation units, wherein the working condition of the tunnel boring machine includes the power, rotation speed, degree of drill bit wear, tunneling speed, and degree of ore and rock crushing of the tunnel boring machine during the tunneling process;

[0045] (3) calculating the tunneling rate of the tunnel boring machine for each minimum measurement and evaluation unit, and establishing a tunnel boring machine working condition record database;

[0046] (4) setting a minimum measurement and evaluation unit, scoring and summing the rock mass quality classification indicators of each minimum measurement and evaluation unit based on the rock mass quality classification standard, and obtaining the rock mass quality classification result of each minimum measurement and evaluation unit;

[0047] (5) establishing a rock mass quality classification database, and recording the rock mass quality classification index, the rock mass quality classification result, and the tunneling rate of the tunnel boring machine of each minimum measurement and evaluation unit in the rock mass quality classification database;

[0048] (6) Based on the rock mass quality classification database, the rock mass quality is rated and classified in real time according to the tunneling speed of the tunnel boring machine.

[0049] In the above basic implementation method, the rock mass is divided into several minimum measurement and evaluation units along the length direction, and a tunnel boring machine is used to excavate each minimum measurement and evaluation unit for a certain length to obtain the tunnel boring machine working condition corresponding to each minimum measurement and evaluation unit. A tunnel boring machine working condition record database is established based on the obtained tunnel boring machine working condition, and the tunnel boring machine advancement rate corresponding to each minimum measurement and evaluation unit is obtained by calculating the data contained in the tunnel boring machine working condition. By making a one-to-one correspondence between the tunnel boring machine advancement rate corresponding to each minimum measurement and evaluation unit and the rock mass quality classification result, when the tunnel boring machine is used to excavate other rock masses, the rock mass quality classification result of the rock mass currently being excavated can be obtained by using the tunnel boring machine advancement rate, which can quickly and accurately reflect the rock mass quality classification of the roadway or tunnel project, making the classification result more accurate and reliable.

[0050] Preferably, the minimum measurement and evaluation unit is set to be 3 m of footage of one operation cycle, so that the minimum measurement and evaluation unit is more reasonable, thereby improving the accuracy and reliability of the evaluation results.

[0051] Specifically, the rock quality grading indicators include the intact rock strength index, rock quality index, rock joint spacing index, rock joint status index and groundwater status index. The above rock quality grading indicators of each minimum measurement and evaluation unit are scored based on the rock quality grading standard, and the score values of the intact rock strength index, rock quality index, rock joint spacing index, rock joint status index and groundwater status index of each minimum measurement and evaluation unit are summed up respectively to obtain the rock quality grading result of each minimum measurement and evaluation unit.

[0052] Furthermore, a rock mass quality classification database is established, and the rock mass quality classification result of each minimum measurement and evaluation unit and the tunneling rate of the tunnel boring machine are stored in the rock mass quality classification database. The rock mass quality classification result of each minimum measurement and evaluation unit and the tunneling rate of the minimum measurement and evaluation unit are stored in the rock mass quality classification database in a one-to-one correspondence. When the tunneling rate is obtained by calculation, the corresponding rock mass quality classification result can be obtained through the rock mass quality classification database.

[0053] Furthermore, within the minimum measurement and evaluation unit, samples are taken from the rock fragments after the tunnel boring machine breaks the rock. The number of samples taken in each minimum measurement and evaluation unit is not less than 5, and the samples are numbered and recorded. In a specific embodiment, the samples can be standard uniaxial compression samples (size Φ50×100mm) for uniaxial compression testing, or irregular samples can be taken for point load testing. For the sake of simplicity, the following mainly describes the point load test with irregular samples as an example. Of course, standard uniaxial compression samples can also be taken for uniaxial compression testing. For those skilled in the art, based on the knowledge of the technical solution of the present invention, it is achievable to use standard uniaxial compression samples for uniaxial compression testing, and no further details will be given.

[0054] In a specific embodiment, Figure 3 As shown in the figure, the sample size of the point load test needs to meet the requirements of the irregular rock point load test in order to carry out the irregular rock point load test and obtain the load when the rock breaks. The equivalent diameter of the sample is calculated according to the sample size, and the point load strength of the sample is calculated based on the load when the sample breaks. The point load strength is corrected to obtain the corrected point load strength index, thereby obtaining the complete rock strength index. The point load strength correction method is as follows:

[0055] a. Uncorrected point load strength index calculation

[0056]

[0057]

[0058] Where Is is the point load strength index before correction, P is the load when the specimen fails, De is the equivalent diameter of the specimen, W is the average width of the minimum cross section passing through the two loading points, and D is the distance between the loading points;

[0059] b. Point load strength index correction

[0060] I s50 =f×I s

[0061] f=(D e / 50) m

[0062] Among them I s50 is the corrected point load strength index, f is the correction factor, m is the correction factor index, which is 0.5;

[0063] The corrected point load strength index, namely the rock strength index, is obtained through calculation.

[0064] Furthermore, the minimum measurement and evaluation unit was drilled and the core of the minimum measurement and evaluation unit was obtained. The actual length of the core greater than 10 cm was measured and summed. Based on the drilling information, the rock quality index of the rock mass within the depth range of a single drilling hole was obtained. The calculation formula is as follows:

[0065]

[0066] Furthermore, a joint and fissure survey is conducted on the rock mass within the minimum measurement and evaluation unit, and a structural surface scan is performed on the stope or tunnel to obtain the total number of joints and fissures in the rock mass within the minimum measurement and evaluation unit, and the rock mass joint spacing index is calculated:

[0067] The joint spacing index is equal to the drilling depth of a single borehole / the total number of joints and fissures in the rock mass passed by the borehole within the range of the single borehole depth.

[0068] Furthermore, the joint surface status within the minimum measurement and evaluation unit is investigated and recorded, the corrosion and roughness of the joint surface are observed, and the joint status index within the minimum measurement and evaluation unit is obtained based on the roughness, corrosion and closure degree of the joint surface of the rock mass through which the borehole passes.

[0069] According to the rock quality classification standard, the complete rock strength index, rock quality index, rock joint spacing index, rock joint state index and groundwater state index of each minimum measurement and evaluation unit are scored, and then the score values of the complete rock strength index, rock quality index, rock joint spacing index, rock joint state index and groundwater state index of each minimum measurement and evaluation unit are summed up respectively to obtain the rock quality classification result of each minimum measurement and evaluation unit.

[0070] Furthermore, the working conditions of the TBM within the minimum measurement and evaluation unit were counted, and the time required for the TBM to complete the rock excavation work within a single minimum measurement and evaluation unit under normal working conditions was obtained. The advancement rate of the TBM was calculated, and the wear of the TBM drill bit was observed. The method for calculating the TBM advancement rate is as follows:

[0071]

[0072] Furthermore, through the rock quality grading method based on the working conditions of the tunnel boring machine of the present invention, when the tunnel boring machine is excavating the rock, the tunneling rate of the tunnel boring machine is obtained by obtaining the current working conditions of the tunnel boring machine. According to the rock quality grading database, the obtained excavation rate is input into the rock quality grading database to obtain the rock quality grading result of the rock currently being excavated.

[0073] Through the above technical solution, the rock mass quality grading method based on the working condition of the tunnel boring machine provided by the present invention obtains the tunnel boring machine working condition of each minimum measurement and evaluation unit by dividing the minimum measurement and evaluation unit and using the tunnel boring machine to perform tunnel boring. The tunnel boring rate is calculated based on the tunnel boring machine working condition and a tunnel boring machine working condition record database is established. According to the rock mass quality grading standard, the complete rock strength index, rock quality index, rock joint spacing index, rock joint state index and groundwater state index of each minimum measurement and evaluation unit are scored and summed to obtain the rock mass quality grading result of each minimum measurement and evaluation unit. The tunnel boring rate and rock mass quality grading result of each minimum measurement and evaluation unit are stored in a one-to-one correspondence in the rock mass quality grading database. When performing other rock mass grading, the rock mass quality grading result is obtained. During the excavation of a rock mass, the excavation rate of the rock mass is obtained by obtaining the current working condition of the rock mass boring machine. According to the rock mass quality grading database, the obtained excavation rate is input into the rock mass quality grading database to obtain the rock mass quality grading result of the rock mass currently being excavated. The present invention scores and grades the rock mass in the minimum measurement and evaluation unit based on data such as underground prospecting geological drilling cores, rock strength characteristics after rock breaking by the rock boring machine, joint and fissure characteristics of the tunnel face, and groundwater status, and matches it with the excavation rate of the rock mass boring machine in real time, thereby establishing a rock mass quality grading database. The real-time evaluation and grading of rock mass quality improves the accuracy and timeliness of rock mass quality grading in underground metal mines, thereby ensuring the safety of underground personnel and equipment and reducing support costs.

[0074] The preferred embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0075] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will no longer separately describe various possible combinations. As long as they do not violate the ideas of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A rock mass quality classification method based on the working conditions of a tunnel boring machine, characterized in that: The steps include: (1) Determine the minimum rock mass quality evaluation unit and divide the entire rock mass length range into several minimum measurement evaluation units; (2) Obtaining the working condition of the tunnel boring machine corresponding to each of the minimum measurement and evaluation units, wherein the working condition of the tunnel boring machine includes the power, rotation speed, degree of drill bit wear, tunneling speed, and degree of ore and rock crushing of the tunnel boring machine during the tunneling process; (3) Calculating the tunneling rate of the tunnel boring machine for each minimum measurement and evaluation unit, and establishing a tunnel boring machine working condition record database; (4) scoring and summing the rock mass quality classification indicators of each of the minimum measurement and evaluation units based on the rock mass quality classification standard to obtain the rock mass quality classification results of each of the minimum measurement and evaluation units, wherein the rock mass quality classification indicators include intact rock strength index, rock quality index, rock mass joint spacing index, rock mass joint state index and groundwater state index; In the minimum measurement and evaluation unit, rock fragments after the tunnel boring machine breaks the rock are sampled and subjected to an irregular rock point load test. The point load strength is corrected and a corrected point load strength index is calculated. The point load strength correction method is as follows: a. Uncorrected point load strength index calculation Where Is is the point load strength index before correction, P is the load when the specimen fails, De is the equivalent diameter of the specimen, W is the average width of the minimum cross section passing through the two loading points, and D is the distance between the loading points; b. Point load strength index correction Among them I s50 is the corrected point load strength index, f is the correction factor, and m is the correction factor index; (5) establishing a rock mass quality classification database, and recording the rock mass quality classification index, the rock mass quality classification result, and the tunneling rate of the tunnel boring machine of each minimum measurement and evaluation unit in the rock mass quality classification database; (6) Based on the rock mass quality classification database, the rock mass quality is rated and classified in real time according to the tunneling speed of the tunnel boring machine.

2. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 1 is characterized in that: The minimum measurement and evaluation unit length is 3m within the footage length of one operation cycle.

3. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 1, characterized in that: Based on the downhole geological exploration drilling core data, the actual length of the core greater than or equal to 10 cm in a single hole is measured and summed up. The calculation formula is as follows: 。 4. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 3 is characterized in that: The number of joints and fissures in a single borehole is statistically recorded based on the borehole image of the single borehole, the total number of joints and fissures in the rock mass passed by the borehole within the depth range of the single borehole is obtained, and the rock mass joint spacing index is calculated: The joint spacing index is equal to the drilling depth of a single borehole / the total number of joints and fissures in the rock mass passed by the borehole within the range of the single borehole depth.

5. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 4 is characterized in that: The joint surface status within the minimum measurement and evaluation unit is investigated and recorded, the corrosion and roughness of the joint surface are observed, and the rock joint status index within the minimum measurement and evaluation unit is judged based on the roughness, corrosion and closure degree of the joint surface.

6. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 5, characterized in that: Obtain the water flow and duration of the rock mass within the minimum measurement and evaluation unit, and determine the groundwater status indicators of the rock mass based on the water flow and duration.

7. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 1, characterized in that: The tunneling rate of the tunnel boring machine within the minimum measurement and evaluation unit is counted, and the time it takes for the tunnel boring machine to complete the tunneling work within a single minimum measurement and evaluation unit under normal working conditions is obtained. The tunneling rate of the tunnel boring machine is calculated, and the wear of the tunnel boring machine drill bit is observed at the same time. The tunneling rate calculation method of the tunnel boring machine is as follows: 。 8. The rock mass quality classification method based on the working condition of the tunnel boring machine according to claim 1, characterized in that: During the tunneling process of the tunnel boring machine, the tunneling rate is calculated and the corresponding rock mass quality classification result is obtained based on the rock mass classification database established in step 5.

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