Construction-oriented method for identifying surrounding rock properties and selecting tunnel support parameters

Abstract

SOLUTION: To provide a method for identifying surrounding rock properties and selecting tunnel support parameters comprising the steps of acquiring basic geological data of a section tunnel, creating a model of the relative positional relationship between the section tunnel and the stratum, and determining a chamber environment classification of the rock surrounding the section tunnel, determining the rock completeness of the rock surrounding the section tunnel based on the basic geological data, determining the degree of groundwater development of the rock surrounding the section tunnel based on the basic geological data, determining the presence or absence of a slide surface of the rock surrounding the section tunnel based on the basic geological data, and selecting support parameters corresponding to support measures based on the chamber environment classification of the properties of the surrounding rock, the rock completeness, the degree of groundwater development, and the presence or absence of a slide surface.EFFECT: This solves the problem of insufficient logic and low accuracy in the conventional design method for surrounding rock mass grading, and reduces the construction costs of single-track sections of mines while ensuring safety.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the technical field of tunnel construction, in particular, to the determination of surrounding rock properties based on construction orientation and and a tunnel support parameter selection method. [Background technology]

[0002] A subway line is made up of stations and sections. Sections are the main arteries connecting the stations at both ends, and account for approximately 80% of the line length. 0%. The construction process for single-track sections under the Mining Act is complicated, the risks are high, and the construction costs are high. Therefore, rational and economical support parameters are required. It is necessary to determine how to design the

[0003] At present, the most commonly used design method for the support parameters of single-track sections in mines in China is Based on the surrounding rock mass classification provided by the surveying agency, combined with experience from construction work, In this study, we designed support systems for different surrounding rock mass grades, and as shown in Fig. 2, Each section corresponds to one support system. This brings about three problems. First, the conventional surrounding rock The classification of foundations does not take into account the characteristics of underground construction and is not applicable to any construction at a certain position. The surrounding rock mass classification is fixed and reflects the geological risk according to the construction characteristics. As a result, it is difficult to grasp the nature of the problem when designing support measures. Second, a single surrounding rock class category may include a combination of multiple surrounding rock conditions. Third, a single surrounding rock mass classification may be used for various types of support. In order to meet the above requirements and ensure the safety of construction, such general support design methods are often used. The design is such that excessive support is likely to occur, resulting in a large amount of manpower and material being wasted. It becomes like this.

[0004] For example, the currently widely used "Urban Rail Transit Rock and Earthworks Survey Standards" includes the following criteria: Regarding the part, "When there is groundwater in the surrounding rock of III, IV, and V class, specific situation and construction The classification of the surrounding rock can be appropriately reduced depending on the conditions. Therefore, when the local investigation agency provides the design institute with a surrounding rock mass grade of V, the surrounding rock mass itself is Due to the influence of the rock structure, the localized mass may be V-class, and the surrounding rock mass itself is IV-class. However, because of groundwater, it may fall to V class. In the surrounding rock support system, pre-grouted pipes are used in the arch section of the section, and the lattice steel frame is The interval between the frames is 0.75m, the thickness of the shotcrete is 250mm, and the walls on both sides are The system anchor bolts are placed at 1.2m x 1.2m. If pipes are cast into the support structure, the grid intervals should be 1m, and the system anchor bolts on both sides should be It is possible to omit the installation of a support. For this reason, the current initial support design is Regarding rock grade classification,

[0005] Because envelope design was carried out for the most unfavorable conditions, a large amount of construction work was wasted. The present invention addresses the above problems by providing a method for determining the chamber environment, rock integrity, and The surrounding rock mass of the section tunnel including indicators such as the development of joint fractures, groundwater development, and local sliding surfaces Based on the properties, a method for designing support parameters is provided, and the actual surrounding rock mass classification step is By omitting the above, the index of the surrounding rock mass properties is directly related to the support parameters of the support measures, Overcome the problem of wasteful construction work caused by insufficient logic and poor accuracy in the design method of the I obeyed. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention is based on the idea that the conventional design method for the surrounding rock mass classification is insufficient in logic and low in accuracy. Solving the problem and avoiding the disadvantages of over- and under-designing support parameters in section tunnels Based on the construction orientation that can reduce the construction cost of the single-track section of the Mining Law while ensuring safety, A method for determining the nature of surrounding rock and selecting tunnel support parameters is provided. [Means for solving the problem]

[0007] The method for identifying surrounding rock mass properties and selecting tunnel support parameters based on construction orientation according to the present invention There was, Obtain basic geological data for the tunnel section and create a model of the relative positional relationship between the tunnel section and the strata. 1 to determine a chamber environment classification for the surrounding rock of the tunnel section; Step 2 is to determine the rock integrity of the surrounding rock mass of the tunnel section based on geological foundation data; , Step 3: Determine the degree of groundwater development in the rock surrounding the tunnel section based on geological foundation data. and, Step 4 is to determine whether there is a slip surface in the rock surrounding the tunnel section based on geological foundation data; , Based on the chamber environmental classification of the surrounding rock properties, rock integrity, groundwater development, and presence or absence of slide surface, and step 5 of selecting support parameters corresponding to the support measures.

[0008] Preferably, step 1 comprises: Based on the rock-saturated uniaxial compressive strength of the geological foundation data, the circumference of the arch of the tunnel section The hardness of the rock mass is determined, and the arch of the tunnel section is divided into hard rock area, relatively hard rock area, and Step 11 of dividing the area into relatively soft rock areas and other geological formation areas; Based on the results of the classification, the first and second safety thicknesses of the cover rock above the arch of the tunnel section were determined. Step 12 of determining the total thickness and the third safety thickness; Based on the geological foundation data, the first section from the arch of the tunnel section to the boundary of the top of the hard rock area determining a distance, and if the first distance is equal to or greater than a first safe thickness, Step 13, which classifies it as Category A; If the first distance is less than the first safety thickness, the tunnel section arch to the top of the relatively hard rock area a second distance to the boundary line of the tunnel section; and if the second distance is equal to or greater than a second safe thickness, Step 14 of classifying the chamber environment during the test as Category B; If the second distance is less than the second safe thickness, the tunnel section arch to the top of the relatively soft rock area A third distance to the boundary line is determined, and if the third distance is equal to or greater than the third safe thickness, the tunnel section and classifying the chamber environment in category C.

[0009] Preferably, step 12 comprises: Based on the basic geological data, the equivalent fracture zone of the rock layer where the tunnel section is located is calculated using the following formula: Calculate the thickness L, TIFF2024177045000002.tif1566 formula, r t is the equivalent circular radius of the tunnel, where In TIFF2024177045000003.tif1032, A is the cross-sectional area of ​​the tunnel, γ is the weight of the surrounding rock, and f r is the uniaxial compression of rock Step 121, where h is the buried depth of the tunnel; determining a minimum cover rock thickness for each rock layer area of ​​the ceiling of the tunnel section; The minimum overburden thickness in the hard rock area is TIFF2024177045000004.tif1219, The minimum thickness of the overburden rock in the relatively hard rock area is TIFF2024177045000005.tif1117, The minimum thickness of the overburden rock in the relatively soft rock area is TIFF2024177045000006.tif1118, where P is the earth pressure in the entire strata above the arch, B is the width of the section, and σ is the curvature of the rock. Step 122, which is the bending strength; Based on the equivalent fracture rock thickness L and the minimum cover rock thickness of each rock layer area of ​​the ceiling plate of the tunnel section, The first, second and third safety thicknesses of the covering rock above the arch of the tunnel section were and determining 123 the total thickness.

[0010] Preferably, step 123 comprises: Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the hard rock region 1 Based on this, the tunnel section determining 1231 a first safe thickness S1 of the overburden rock above the arch; Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the relatively hard rock region 2 Based on the tunnel section determining 1232 a second safe thickness S2 of the cover rock above the arch between the arches; Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the relatively soft rock zone 3 Based on the tunnel section and determining a third safe thickness S3 of the cover rock above the arch. .

[0011] Preferably, step 2 comprises: Based on geological foundation data, the rock compression wave velocity of the surrounding rock environment where the tunnel section arch is located Degree u and rock mass compressional wave velocity u 0 Step 21 of determining Rock compressional wave velocity u and rock mass compressional wave velocity u 0 Based on this, the integrity factor of the tunnel section Step 22, which calculates TIFF2024177045000007.tif914; The perfection coefficient k determines the circumference where the arch is located according to a predefined rock perfection classification table. and determining 23 the rock integrity of the surrounding rock mass.

[0012] Preferably, the rock completeness is determined according to a preset rock completeness classification table. They can be divided into three types:

[0013] Preferably, step 3 comprises: Based on the geological foundation data, the distance h from the center of the tunnel section to the groundwater level line, and each layer The thickness h from the groundwater level to the center of the tunnel section i and a step 31 of determining Based on the geological basic data, the permeability coefficient k of each layer above the center of the tunnel section below the groundwater level i of A step 32 of determining formula Step 33 of calculating the overall hydraulic conductivity K according to TIFF2024177045000008.tif1123; Equivalent circular radius of the tunnel section 34. Calculate TIFF2024177045000009.tif923, where A is the area of ​​the tunnel section; Based on the geological basic data, the amount of spring water per linear meter of the section Q 0 Calculate and determine Step 35 and The amount of spring water per 1 meter of the section 0 The groundwater development level is classified according to the predefined table. Step 36 of classifying the degree of groundwater growth in the rock surrounding the tunnel section into developed and non-developed based on the above. Including,

[0014] Preferably, in step 4, the tunnel section is determined based on the geological foundation data to have a large geological structure. If the wall penetrates a large structural surface, a sliding surface is present and the wall is unable to penetrate a large structural surface. This includes steps where there is no sliding surface unless the step penetrates the structural face.

[0015] Preferably, step 5 comprises: The surrounding rocks of the tunnel section, including chamber environmental classification, rock integrity, groundwater development, and presence or absence of slide surface Step 51 of determining four indices of board properties; A step 52 of determining a selection sheet of pre-defined structural support parameters; Based on the four indices of the nature of the surrounding rock mass of the tunnel section, the preset structural support parameters are Select the support parameters for each of the support measures according to the meter selection sheet. and a step 53 of searching.

[0016] Preferably, from the determination results of the support parameters corresponding to each of all the support measures, The method further includes a step 6 of determining a design plan of a corresponding support parameter cross section. Effect of the Invention

[0017] According to the present invention, the conventional design method of surrounding rock mass classification is insufficient in logic and low in accuracy. This can solve the problem of over- and under-design of support parameters in section tunnels. It is necessary to reduce the construction costs of single-track sections under the Mining Law while avoiding the above problems and ensuring safety. can.

[0018] Other features and advantages of the invention will be described in, and in part will be apparent from, the following specification. The objectives and other advantages of the present invention will become apparent from the following description, or may be learned by the practice of the invention. The present invention is achieved by the features particularly pointed out in the specification, claims and drawings. It can be done.

[0019] The technical solution of the present invention will be described in more detail below with reference to the drawings and examples.

[0020] The drawings are included to provide a further understanding of the invention, are a part of the specification, and are incorporated in and constitute a part of the present invention. These examples are used to illustrate the present invention and are not intended to limit the present invention. [Brief description of the drawings]

[0021] [Figure 1] 2 is a flowchart showing steps of a method for determining surrounding rock mass properties and selecting tunnel support parameters based on a construction orientation according to an embodiment of the present invention. [Diagram 2] This is a diagram of design concepts that explain the shortcomings of the design concepts of normal mining law single-track sections. [Diagram 3] FIG. 13 is a diagram showing the correspondence relationship between support parameters and surrounding rock properties. [Figure 4] FIG. 2 is a schematic diagram of a chamber environment for a section tunnel category A according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a schematic diagram of a chamber environment of a section tunnel category B according to an embodiment of the present invention. [Figure 6] 1 is a schematic diagram of a chamber environment of a section tunnel category C according to an embodiment of the present invention; [Figure 7] This is a schematic diagram of the calculation of the amount of spring water Q0 per linear meter of a section tunnel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. The preferred embodiment is only used to explain and explain the present invention, and the present invention It should be understood that this is not intended to be limiting.

[0023] The core of this invention is to provide two new methods based on the surrounding rock properties of a single track section. One is a method for determining the surrounding rock environment of a single-track section of a mine, and the other is a method for determining the surrounding rock environment of a section tunnel. The former method is a method for selecting the proper support parameters. This is the premise, and the section designer can use this invention to accurately determine the support parameters of the single-track section under the Mining Act. This allows efficient design of the support parameters and surrounding rock properties. The indices of the surrounding rock properties are mainly the chamber environmental classification, rock The parameters include the stone integrity, groundwater development, and the presence or absence of a slide surface. concrete thickness, triangular lattice steel frame spacing, steel mesh model and spacing, pre-glazed Includes welded pipe model and spacing, and anchor bolts.

[0024] The chamber environments are classified into Category A, Category B, and Category C. Rock integrity is divided into three grades: complete, relatively complete, and relatively destroyed. Groundwater development is divided into developed and undeveloped categories. The presence or absence of a sliding surface can be divided into two categories: present and absent.

[0025] The support parameter design method according to the present invention separates the support effects of each support measure, This is the basis for matching the surrounding rock mass property index with the support parameters, as shown in Fig. 3. The support effect of the separated support measures is analyzed as follows. 1. Shotcrete: Shotcrete has two main roles. The first is to bond the cracks and joints and to keep out water and air. The second is to protect the surrounding area. To improve the stress state of the rock mass, provide radial support, and increase the strength of the surrounding rock mass. Therefore, the shotcrete thickness parameter is determined based on the chamber environmental classification and rock completeness. The correlations are only with two surrounding rock mass property indicators: 2. Triangular lattice: As for the role of triangular lattice, it is usually used in conjunction with shotcrete. It has two main roles: first, to limit the deformation of the surrounding rock mass together with the shotcrete; The other is to act as a support for the pre-grouting pipe. Therefore, the selection of the triangular lattice spacing parameter is based on the classification of the rock environment around the chamber and the rock mass. It is not only related to the stone integrity but also to the parameters of the pre-grouting pipe. 4. The pre-grouting pipe supports the surrounding area, which is the degree of groundwater development and rock integrity. It was found to correspond to the rock mass property index. 3. Steel mesh: Steel mesh is also commonly combined with shotcrete. It is used mainly to increase the integrity and toughness of the shotcrete. Therefore, the selection of steel mesh parameters is also based on two criteria: chamber environment classification and rock integrity. This is related only to the surrounding rock mass property index. 4. Pre-grouted pipe: Pre-grouted pipe supports are generally made of pre-grouted pipes. This refers to reinforcement by grouting through a grout pipe. Grouting is used to reinforce weak, loose or powdery soil. It is injected into the fractures of the surrounding fractured, hydrous rock and is then allowed to solidify in intimate contact with it. Therefore, the selection of pre-grouting pipe parameters depends on the rock integrity and groundwater development. Only relevant. 5. Anchor bolt: The main role of an anchor bolt is to fix a loose rock mass to a stable rock body. The aim of this study is to strengthen the integrity of the surrounding rock mass locally by applying the anchor bolt parameters. The selection of data is related only to the surrounding rock mass property indicator, i.e., the presence or absence of a slide surface.

[0026] The method for identifying surrounding rock mass properties and selecting tunnel support parameters based on construction orientation according to the present invention is ,As shown in Figure 1, Obtain basic geological data for the section tunnel and create a model of the relative position between the section tunnel and the strata. Step 1 to determine the chamber environment classification of the surrounding rock of the section tunnel by creating Step 2 is to determine the rock integrity of the surrounding rock mass of the section tunnel based on geological foundation data; , Step 3: Determining the degree of groundwater development in the rock surrounding the section tunnel based on geological foundation data and, Step 4 is to determine whether there is a slip surface in the rock surrounding the section tunnel based on geological foundation data; , Based on the chamber environmental classification of the surrounding rock mass properties, rock integrity, groundwater development, and presence or absence of slide surface, and step 5 of selecting support parameters corresponding to the support measures.

[0027] In one preferred embodiment, the geological foundation data includes a geological exploration report.

[0028] The working principle and beneficial effects of the above technical solution are as follows: , Chamber environment classification of surrounding rock properties of section tunnel, rock integrity, groundwater development degree, slip surface Determine the presence or absence and, based on this, select the support parameters corresponding to the support measures to be used As a result, the logic of the conventional design method for the surrounding rock mass classification is insufficient and the accuracy is low. This can solve the problem of over- and under-design of support parameters in section tunnels. To reduce the construction costs of single-track sections under the Mining Law while avoiding the drawbacks of using multiple feet and ensuring safety. can be done.

[0029] In one preferred embodiment, as shown in FIGS. 4 to 6, step 1 includes: Based on the rock-saturated uniaxial compressive strength of the geological foundation data, the circumference of the arch of the section tunnel The hardness of the rock mass is determined, and the arches of the section tunnel are divided into hard rock areas, relatively hard rock areas, and Step 11 of dividing the area into relatively soft rock areas and other geological formation areas; Based on the results of the section, the first and second safety thicknesses of the cover rock above the arch of the section tunnel were determined. Step 12 of determining the total thickness and the third safety thickness; Based on the geological foundation data, the first section from the arch of the section tunnel to the boundary of the top of the hard rock area determining a distance, and if the first distance is equal to or greater than a first safe thickness, Step 13, which classifies it as Category A; If the first distance is less than the first safety thickness, the arch of the section tunnel to the top of the relatively hard rock area A second distance to the boundary line of the tunnel section is determined, and if the second distance is equal to or greater than the second safe thickness, the tunnel section is Step 14, classifying the chamber environment of the device as Category B; If the second distance is less than the second safe thickness, the tunnel arch is located at the top of the relatively soft rock area. A third distance to the boundary line is determined, and if the third distance is equal to or greater than the third safe thickness, the section tunnel is and classifying the chamber environment in category C.

[0030] The working principle and beneficial effects of the above technical solution are as follows: The hardness of the rock surrounding the arch of the section tunnel is determined based on the rock-saturated uniaxial compressive strength, and the hardness Depending on the section tunnel arch, hard rock area, relatively hard rock area, relatively soft rock area and other strata are The division will be made into regions according to the following table:

[0031] Table 1. Rock hardness classification table TIFF2024177045000010.tif26146

[0032] Based on the results of the section, the first and second safety thicknesses of the cover rock above the arch of the section tunnel were determined. Determine the total thickness and the third safe thickness, and determine the thickness from the arch of the section tunnel based on the geological foundation data. Determine the first distance to the boundary line of the top of the hard rock area (positive if the arch is below the boundary line). distance, and conversely, a negative distance), if the first distance is equal to or greater than the first safe thickness, If the tunnel chamber environment is classified as Category A and the first distance is less than the first safety thickness, , determining a second distance from the arch of the section tunnel to the boundary of the top of the relatively hard rock region; If the distance between the two tunnels is equal to or greater than the second safety thickness, the chamber environment of the tunnel section is classified as Category B. If the second distance is less than the second safe thickness, the arch of the section tunnel is located in a relatively soft rock area. A third distance to the boundary line of the top is determined, and if the third distance is equal to or greater than the third safe thickness, the section If the chamber environment of the channel is classified as Category C and the third distance is less than the third safety thickness, The staff was advised to carry out a special design of the support parameters, which would improve the channel strength of the section tunnel. This has achieved a scientific classification of the Mamba environment.

[0033] In one preferred embodiment, step 12 comprises: Based on the basic geological data, the following formula is used to determine the isostatic fracture zone of the rock layer where the tunnel section is located: Calculate the thickness L, TIFF2024177045000011.tif1566, r t is the equivalent circular radius of the tunnel, where In TIFF2024177045000012.tif1032, A is the cross-sectional area of ​​the tunnel, γ is the weight of the surrounding rock, and f r is the uniaxial compression of rock is the strength, h is the buried depth of the tunnel, and the equivalent circular radius of the tunnel is the section tunnel Step 121, which is the equivalent circular radius of the cross section of determining a minimum cover rock thickness for each rock layer area of ​​the ceiling of the tunnel section; The minimum overburden thickness in the hard rock area is TIFF2024177045000013.tif1219, The minimum thickness of the overburden rock in the relatively hard rock area is TIFF2024177045000014.tif1117, The minimum thickness of the overburden rock in the relatively soft rock area is TIFF2024177045000015.tif1118, where P is the earth pressure in all layers above the arch (MPa m) and B is the width of the space (m). Step 122, where σ is the bending strength of the rock (MPa); Based on the isostatic rock zone thickness L and the minimum covering rock thickness of each rock layer area of ​​the ceiling plate of the tunnel section, The first, second and third safety thicknesses of the covering rock above the arch of the tunnel section were and determining 123 the total thickness.

[0034] The beneficial effects of the above technical proposal are as follows: Cladding above the arch of the section tunnel The first safe thickness, second safe thickness and third safe thickness of the rock are calculated.

[0035] In one preferred embodiment, step 123 includes: Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the hard rock region 1 Based on this, the section tunnel The first safe thickness H of the cover rock above the arch 1 Determine where H 1 =1.3(L+H1 ), step 1231; Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the relatively hard rock region 2 Based on the section tunnel The second safe thickness H of the cover rock above the arch of the 2 Determine where H 2 =1.3(L +H 2 ), step 1232; Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the relatively soft rock zone 3 Based on the section tunnel The third safe thickness H of the cover rock above the arch 3 Determine where H 3 =1.3(L+ H 3 ), and step 1233.

[0036] The working principle of the above technical solution is as follows: The covering rock above the arch of the section tunnel The first safety thickness, the second safety thickness and the third safety thickness are accurately calculated.

[0037] In one preferred embodiment, step 2 comprises: Rock compression wave velocity of the surrounding rock environment where the arch of the section tunnel is located based on geological foundation data Degree u and rock mass compressional wave velocity u 0 Step 21 of determining Rock compressional wave velocity u and rock mass compressional wave velocity u 0 Based on this, the integrity factor of the section tunnel is Step 22, which calculates TIFF2024177045000016.tif59; The perfection coefficient k determines the circumference where the arch is located according to a predefined rock perfection classification table. and determining 23 the rock integrity of the surrounding rock mass.

[0038] In one preferred embodiment, the rock integrity is determined according to a pre-defined rock integrity classification table. There are three types of damage: complete, relatively complete, and relatively destroyed. The classification is as follows: This is carried out.

[0039] Table 2. Rock perfection classification table TIFF2024177045000017.tif22157

[0040] The beneficial effects of the above technical proposal are as follows: The surrounding rocks where the arch of the section tunnel is located are Determination and classification of rock integrity of the bedrock is achieved.

[0041] In one preferred embodiment, as shown in FIG. 7, step 3 includes: Based on the geological foundation data, the distance h from the center of the section tunnel to the groundwater level line, and each layer The thickness h from the groundwater level to the center of the section tunnel i and a step 31 of determining Based on the geological basic data, the permeability coefficient k of each layer above the center of the tunnel in the section below the groundwater level i of A step 32 of determining formula Step 33 of calculating the overall hydraulic conductivity K according to TIFF2024177045000018.tif717; Equivalent circular radius of the tunnel section Step 34: Calculate TIFF2024177045000019.tif923, where A is the area of ​​the tunnel section; The amount of spring water per linear meter of the section based on basic geological data Step 35 of calculating and determining TIFF2024177045000020.tif921; The amount of spring water per 1 meter of the section 0 According to the pre-defined groundwater development classification table, Step 36: Classifying the degree of groundwater development in the rock surrounding the section tunnel into developed and non-developed based on the above. The classification is made according to the table below.

[0042] Table 3. Classification of groundwater development TIFF2024177045000021.tif27151

[0043] The beneficial effects of the above technical proposal are as follows: The degree of groundwater development in the surrounding rock of the section tunnel are classified.

[0044] In one preferred embodiment, the step 4 comprises: determining a section tunnel based on geological foundation data; It is judged whether the rock is penetrating a large stratum structure surface. If it is penetrating a large stratum structure surface, it is judged that a slide surface exists. This includes steps where there is no sliding surface unless there is a large structural surface penetrating through.

[0045] The beneficial effects of the above technical proposal are as follows: The section tunnel penetrates a large geological structure surface; If the large structural surface is penetrated, a slip surface is present and the large structural surface is penetrated. Otherwise, the absence of a slide surface would cause the surrounding rock mass where the section tunnel is located to slide. Determine whether or not a surface is present.

[0046] In one preferred embodiment, step 5 comprises: The surrounding rocks of the section tunnel, including chamber environment classification, rock integrity, groundwater development, and presence or absence of slide surface Step 51 of determining four indices of board properties; A step 52 of determining a selection sheet of pre-defined structural support parameters; Based on the four indicators of the nature of the surrounding rock mass of the section tunnel, the preset structural support parameters are Select the support parameters for each of the support measures according to the meter selection sheet. The structural support parameters are selected as described in the following sheet. It is selected.

[0047] Table 4. Selection of support parameters for tunnel structures in single-track sections of rocky areas according to the Mining Act TIFF2024177045000022.tif10271 TIFF2024177045000023.tif7370

[0048] The beneficial effects of the above technical proposals are as follows: Chamber environmental classification, rock integrity, groundwater Based on four indicators of the surrounding rock properties, the degree of development, and the presence or absence of a slide surface, The selection of support parameters is realized according to the above.

[0049] In one preferred embodiment, a determination of support parameters corresponding to each of all support measures is performed. The method further includes step 6 of determining a design diagram of a corresponding support parameter cross section from the determination result.

[0050] The working principle and beneficial effects of the above technical solution are as follows: Determine the support parameters and label each part or piece of equipment on the section design drawing with the support parameters. This makes it possible to obtain cross-sectional design drawings of support parameters, facilitating highly accurate construction work. It can be used for.

[0051] Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, it is to be understood that these modifications and variations of the present invention are intended to be included within the spirit and scope of the present invention. The present invention includes these modifications and variations, provided they come within the scope of the appended claims and their equivalents. It is intended that.

Claims

1. A method for identifying surrounding rock mass properties and selecting tunnel support parameters based on construction orientation, comprising: Obtain basic geological data for the section tunnel and create a model of the relative position between the section tunnel and the strata. Step 1: determining a chamber environment classification for the surrounding rock of the section tunnel by creating Step 2: determining the rock integrity of the surrounding rock mass of the section tunnel based on geological foundation data; 、 Step 3: Determine the degree of groundwater development in the rock surrounding the section tunnel based on geological foundation data and, Step 4: determining whether or not there is a slip surface in the rock surrounding the section tunnel based on the geological foundation data; 、 Based on the chamber environmental classification of the surrounding rock mass properties, rock integrity, groundwater development, and presence or absence of slide surface, and step 5 of selecting support parameters corresponding to the support measures. A method for identifying surrounding rock properties and selecting tunnel support parameters based on construction orientation.

2. The step 1 includes: Based on the rock-saturated uniaxial compressive strength of the geological foundation data, the circumference of the arch of the section tunnel The hardness of the rock mass is determined, and the arches of the section tunnel are divided into hard rock areas, relatively hard rock areas, and Step 11 of dividing the area into relatively soft rock areas and other geological formation areas; Based on the results of the section, the first and second safety thicknesses of the cover rock above the arch of the section tunnel were determined. A step 12 of determining a total thickness and a third safe thickness; Based on the geological foundation data, the first section from the arch of the section tunnel to the boundary of the top of the hard rock area determining a distance, and if the first distance is equal to or greater than a first safe thickness, Step 13 of classifying into category A; If the first distance is less than the first safe thickness, the arch of the section tunnel to the top of the relatively hard rock area and if the second distance is equal to or greater than the second safe thickness, Step 14 of classifying the chamber environment of the chamber into category B; If the second distance is less than the second safe thickness, the tunnel arch is located at the top of the relatively soft rock area. A third distance to the boundary line is determined, and if the third distance is equal to or greater than a third safe thickness, the section tunnel is and classifying the chamber environment of the chamber into category C. The method for determining the nature of surrounding rock mass and selecting tunnel support parameters based on the construction orientation described in claim 1. 。

3. The step 12 includes: Based on the basic geological data, the equivalent fracture zone of the rock layer where the section tunnel is located is calculated by the following formula: Calculate the thickness L, In the formula, r ｔ is the equivalent circular radius of the tunnel, where where A is the cross-sectional area of ​​the tunnel, γ is the weight of the surrounding rock, and f ｒ is the uniaxial compression of rock Step 121, where h is the buried depth of the tunnel; determining a minimum cover rock thickness for each rock layer area of ​​the section tunnel ceiling; The minimum overburden thickness in the hard rock area is and The minimum thickness of the overburden rock in the relatively hard rock area is and The minimum thickness of the overburden rock in the relatively soft rock area is and where P is the earth pressure in the strata above the arch, B is the width of the section, and σ is the curvature of the rock. Step 122, which is the bending strength; Based on the equivalent fracture rock thickness L and the minimum covering rock thickness of each rock layer area of ​​the ceiling plate of the section tunnel, The first, second and third safety thicknesses of the covering rock above the arch of the section tunnel were and a step (123) of determining the total thickness. A method for determining the nature of surrounding rock mass and selecting tunnel support parameters based on rock orientation.

4. The step 123 includes: Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the hard rock region １ Based on this, the section tunnel determining 1231 a first safe thickness S1 of the overburden rock above the arch; Equivalent fracture rock zone thickness L and minimum overburden rock thickness H in the relatively hard rock region ２ Based on the section tunnel determining 1232 a second safe thickness S2 of the overburden rock above the arch of the bridge; Equivalent fracture rock zone thickness L and minimum overlying rock thickness H in the relatively soft rock area ３ Based on the section tunnel and determining 1233 a third safe thickness S3 of the cover rock above the arch. The method for determining the nature of surrounding rock mass and tunnel support structure based on the construction-oriented method according to claim 3, How to select parameters.

5. Step 2 includes: Rock compression wave velocity of the surrounding rock environment where the arch of the section tunnel is located based on geological foundation data Degree u and rock mass compression wave velocity u ０ A step 21 of determining Rock compressional wave velocity u and rock mass compressional wave velocity u ０ Based on this, the integrity factor of the section tunnel is A step 22 of calculating The perfection coefficient k determines the circumference where the arch is located according to a pre-defined rock perfection classification table. and determining (23) the rock integrity of the surrounding rock mass. A method for determining the nature of surrounding rock mass and selecting tunnel support parameters based on the above construction orientation.

6. The rock completeness is classified into complete, relatively complete, comparative complete, and comparative complete according to a preset rock completeness classification table. According to the construction-oriented method of the present invention, the construction is divided into three types of destruction: <Method for determining surrounding rock properties and selecting tunnel support parameters.

7. Step 3 includes: Based on the geological foundation data, the distance h from the center of the section tunnel to the groundwater level line, and each layer The thickness h from the groundwater level to the center of the section tunnel ｉ A step 31 of determining Based on the geological basic data, the permeability coefficient k of each layer above the center of the tunnel in the section below the groundwater level ｉ of A determining step 32; formula Step 33 of calculating the overall hydraulic conductivity K by Equivalent circular radius of section tunnel where A is the area of ​​the section tunnel; Based on basic geological data, the amount of spring water per 1 meter of the section ０ Calculate and determine Step 35; The amount of spring water per 1 meter of the section ０ According to the pre-defined groundwater development classification table, Based on the result, the degree of groundwater development in the rock surrounding the section tunnel is classified into developed and non-developed in step 36. The method of determining the nature of surrounding rock mass based on the construction direction according to claim 1, Tunnel support parameter selection method.

8. Step 4 is to determine whether the section tunnel will penetrate a large geological structure based on the geological foundation data. If the large structural surface is penetrated, a sliding surface is present and the large structural surface is penetrated.

2. The construction method according to claim 1, further comprising the step of: A method for identifying surrounding rock properties and selecting tunnel support parameters based on orientation.

9. Step 5 includes: The surrounding rocks of the section tunnel, including chamber environment classification, rock integrity, groundwater development, and presence or absence of slide surface A step 51 of determining four indices of board properties; A step 52 of determining a selection sheet of pre-defined structural support parameters; Based on four indicators of the nature of the surrounding rock mass of the section tunnel, the preset structural support parameters are Select the support parameters for each of the support measures according to the meter selection sheet. and a step (53) of searching for the construction-oriented method according to claim 1. Method for determining surrounding rock properties and selecting tunnel support parameters.

10. From the results of the support parameter judgment corresponding to each of all support measures, the corresponding support parameters are 6. The method according to claim 1, further comprising the step of determining a design drawing of a parameter cross section. A method for determining the properties of surrounding rock mass and selecting tunnel support parameters based on the construction orientation described above.

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