Quantitative method and system for alteration diabase tunnel surrounding rock quality grading

Abstract

The invention relates to the technical field of alteration rock engineering geological characteristics, and discloses a quantification method and system for alteration diabase tunnel surrounding rock quality grading, and the method comprises the steps: collecting diabase with different alteration degrees, carrying out the mineralogical characteristic analysis of the collected diabase with different alteration degrees, and carrying out the type classification of the alteration diabase; defining a factor set and a judgment set; a judgment matrix is constructed through an analytic hierarchy process, and weight vectors are obtained through solution of the feature values and the feature vectors; constructing a fuzzy evaluation matrix through a fuzzy comprehensive evaluation algorithm, multiplying the obtained weight vector by the fuzzy evaluation matrix, calculating the membership degree of each surrounding rock body on each grade through weighted average operation, and forming a fuzzy comprehensive evaluation set; and determining the final grade of each rock mass by utilizing a maximum membership degree principle, thereby realizing the division of the alteration diabase surrounding rock quality grade. According to the method, alteration diabase surrounding rock quality grades are divided, a more reliable division result is obtained, and construction safety is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of engineering geological properties of altered rocks, and in particular to a quantitative method and system for grading the quality of altered diabase tunnel surrounding rocks. Background Art

[0002] Alteration causes the mineral composition and structural structure of rocks to change to varying degrees, thus affecting the physical and mechanical properties of rocks. In particular, clay-altered rocks often constitute major geological defects in engineering rock masses. Diabase is a common rock mass in the Kangdian area of ​​southwest China. As a shallow intrusive basic rock, it often occurs in vein or dyke form. Its mineral composition is mainly pyroxene and basic plagioclase, with a diabase structure, which makes it hard and brittle. It is easy to break under the action of later tectonic dynamics, and is accompanied by varying degrees of clay-altered alteration, thereby deteriorating the mechanical properties of the rock mass. For example, the deformation modulus and compression resistance of altered diabase are significantly reduced, and the uniaxial compressive strength is much lower than that of the original rock. The rock density and longitudinal wave velocity are reduced, and the rock mass quality deteriorates. Diabase is prone to foliation, fragmentation, and even argillaceousness under later tectonic dynamics, and leads to the development of microscopic pores in the altered rock mass, and the engineering properties are very poor.

[0003] At present, although many scholars at home and abroad have carried out a lot of work on the engineering problem of tunnel surrounding rock quality classification, there is still a lack of research on the classification method of specific altered diabase tunnel surrounding rock in these studies, and this problem needs to be solved urgently. Summary of the invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a quantitative method and system for classifying the quality grade of altered diabase tunnel surrounding rocks to solve the problem of lack of a method for classifying the quality grade of tunnel surrounding rocks based on the characteristics of specific altered diabase.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a quantitative method for classifying the quality of surrounding rocks of altered diabase tunnels, comprising:

[0008] Collect diabase with different degrees of alteration, analyze the mineralogical characteristics of the collected diabase with different degrees of alteration, and classify the altered diabase into types;

[0009] Based on the classification of altered diabase types, define factor sets and judgment sets;

[0010] Based on the factor set and the judgment set, the judgment matrix is ​​constructed through the hierarchical analysis method, and the weight vector is obtained by solving the eigenvalue and eigenvector;

[0011] The fuzzy evaluation matrix is ​​constructed by the fuzzy comprehensive evaluation algorithm, the weight vector obtained is multiplied by the fuzzy evaluation matrix, and the membership degree of each surrounding rock mass in each classification is calculated by weighted average operation to form a fuzzy comprehensive evaluation set;

[0012] Based on the membership of each surrounding rock mass in each classification, the maximum membership principle is used to determine the final classification of each rock mass, thus realizing the classification of the quality grade of the altered diabase surrounding rock.

[0013] As a preferred solution of the quantitative method for grading the quality of the altered diabase tunnel surrounding rock of the present invention, wherein:

[0014] The factor set and judgment set include:

[0015] Five key indicators, namely, saturated uniaxial compressive strength, cohesion, integrity coefficient, structural surface characteristic parameters, and alteration index, were selected as the factor set;

[0016] The evaluation set defines the classification standard of surrounding rocks, and divides surrounding rocks into Grade I, Grade II, Grade III, Grade IV, and Grade V, with Grade I being the highest grade, and Grade V surrounding rocks being divided into two sub-classes, V1 and V2;

[0017] As a preferred solution of the quantitative method for grading the quality of the altered diabase tunnel surrounding rock of the present invention, wherein:

[0018] The calculation formula of the alteration index is expressed as:

[0019]

[0020] Among them, ks is the alteration index, x Sem 、x Pl 、x Pyx They are the percentage of clay minerals, plagioclase and pyroxene in altered diabase respectively.

[0021] As a preferred solution of the quantitative method for grading the quality of the altered diabase tunnel surrounding rock of the present invention, wherein:

[0022] The construction of the judgment matrix and obtaining the weight vector by solving the eigenvalue and the eigenvector include the following steps:

[0023] Compare each pair of factors in the factor set to assess the impact on the evaluation target object;

[0024] The 1-9 scale is used for quantification, and a 5×5 order judgment matrix E is constructed;

[0025] Using the characteristic root method, solve the matrix equation EW = λ max , solve the judgment matrix EThe maximum eigenvalue λ max The characteristic vector corresponding to the maximum eigenvalue is W = [W1, W2, ..., W n ] T ;

[0026] Based on the feature vector W, a consistency check is performed;

[0027] Based on the consistency test, the obtained eigenvector is the weight vector of the rock mass evaluation factor

[0028] As a preferred solution of the quantitative method for grading the quality of the altered diabase tunnel surrounding rock of the present invention, wherein:

[0029] The method of constructing a fuzzy evaluation matrix by using a fuzzy comprehensive evaluation algorithm comprises the following steps:

[0030] The obtained weight vector Applied in fuzzy comprehensive evaluation, the fuzzy evaluation matrix is ​​constructed for each indicator;

[0031] Select normal distribution to construct membership function and determine the membership degree of each factor at each evaluation level;

[0032] The membership degree r of each factor in each evaluation level ij Fill in the fuzzy judgment matrix

[0033] As a preferred solution of the quantitative method for grading the quality of the altered diabase tunnel surrounding rock of the present invention, wherein:

[0034] The membership degree of each surrounding rock mass in each classification is expressed as:

[0035]

[0036] Among them, m is the total number of evaluation indicators, a i is the weight value.

[0037] As a preferred solution of the quantitative method for grading the quality of the altered diabase tunnel surrounding rock of the present invention, wherein:

[0038] The method of using the maximum membership principle to determine the final classification of each rock mass includes: according to the maximum membership principle, the membership b of each surrounding rock mass in each classification is j Find the value b with the highest membership among all the evaluation levels j0 , b j0 The corresponding v j This is the final classification of the rock mass.

[0039] In a second aspect, the present invention provides a quantitative system for classifying the quality of altered diabase tunnel surrounding rocks, comprising:

[0040] The classification module is used to collect diabase with different alteration degrees, analyze the mineralogical characteristics of the collected diabase with different alteration degrees, and classify the altered diabase into types;

[0041] Definition module, based on the classification of altered diabase types, defines factor sets and judgment sets;

[0042] The solution module is used to construct a judgment matrix based on the factor set and the judgment set through the hierarchical analysis method, and obtain the weight vector by solving the eigenvalue and eigenvector;

[0043] The calculation module is used to construct a fuzzy evaluation matrix through a fuzzy comprehensive evaluation algorithm, multiply the obtained weight vector with the fuzzy evaluation matrix, calculate the membership degree of each surrounding rock mass in each classification through weighted average operation, and form a fuzzy comprehensive evaluation set;

[0044] The classification module is used to determine the final classification of each rock mass based on the membership of each surrounding rock mass in each classification and using the maximum membership principle, thereby realizing the classification of the quality grades of the altered diabase surrounding rock.

[0045] In a third aspect, the present invention provides a computing device, comprising:

[0046] Memory, used to store programs;

[0047] A processor is used to execute the computer executable instructions, which, when executed by the processor, implement the steps of the quantitative method for classifying the quality grade of the surrounding rock of the altered diabase tunnel.

[0048] In a fourth aspect, the present invention provides a computer-readable storage medium, comprising: when the program is executed by a processor, the steps of implementing the quantitative method for classifying the quality grade of the surrounding rock of the altered diabase tunnel are implemented.

[0049] Beneficial effects of the present invention:

[0050] 1. This invention introduces macroscopic geological characterization, rock mineralogy characteristics, and mechanical tests into the classification of altered diabase and the determination of the degree of rock alteration for the first time, effectively making up for the defect that there is no quantitative determination method at present. In the determination process, not only can the mechanical parameters of the rock mass be directly obtained, but also the mineral percentages of altered diabase with different degrees of alteration can be obtained, which can be directly applied to engineering. The testing means are advanced and the determination method is more novel.

[0051] 2. The additional identification of the degree of alteration in the present invention is a quantitative identification method, which gets rid of the disadvantage of human subjectivity and is more scientific and reasonable than the traditional qualitative method.

[0052] 3. The present invention selects multiple indicators from both macroscopic and microscopic levels for comprehensive discrimination, making the discrimination result more accurate.

[0053] 4. In the present invention, the alteration degree of tectonic altered diabase is mainly divided into: micro-altered diabase (micro), cataclastic altered diabase (weak), cataclastic altered diabase (medium), diabase breccia (relatively strong), foliated diabase (strong), and mud diabase (strong).

[0054] 5. The present invention is suitable for the alteration classification of various types of altered rocks deep underground and the classification research of altered surrounding rocks, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0056] Figure 1 A schematic diagram of the basic process of a quantitative method for grading the quality of surrounding rocks of an altered diabase tunnel provided by an embodiment of the present invention;

[0057] Figure 2 An altered diabase sampling location and macroscopic characteristic diagram of a quantitative method for classifying the quality grade of an altered diabase tunnel surrounding rock provided by an embodiment of the present invention;

[0058] Figure 3 An XRD spectrum of a typical sample of a quantitative method for classifying the quality grade of altered diabase tunnel surrounding rock provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0059] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0060] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0061] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0062] Example 1

[0063] Reference Figure 1 Tables 2 and 3 are an embodiment of the present invention, providing a quantitative method for classifying the quality grade of the surrounding rock of an altered diabase tunnel, including:

[0064] S1: Collect diabase with different alteration degrees, analyze the mineralogical characteristics of the collected diabase with different alteration degrees, and classify the altered diabase into types;

[0065] Furthermore, the uniaxial compressive strength test of rocks with different degrees of alteration was carried out on the collected rock samples to obtain the saturated uniaxial compressive strength and XRD quantitative phase composition analysis of altered diabase with different degrees of alteration. According to the hammer reaction, rock type, structural plane spacing, rock mass structure, clay mineral content and saturated uniaxial compressive strength, the altered diabase rock mass type and alteration degree were first divided, mainly into: micro-altered diabase (micro-altered), cataclastic altered diabase (weakly altered), cataclastic altered diabase (moderately altered), diabase breccia (relatively strongly altered), foliated diabase (strongly altered), and muddy diabase (strongly altered).

[0066] Furthermore, the XRD quantitative phase composition analysis was performed using a Rigaku Ultima IV diffractometer, and for the uniaxial compression test of the rock samples;

[0067] Furthermore, because the secondary clay minerals in the altered diabase are mainly kaolinite and chlorite, the alteration index ks is proposed to characterize the degree of alteration. The alteration index ks is expressed as:

[0068]

[0069] Where: ks is the alteration index, x sem 、x pl 、x pyx They are the percentage of clay minerals, plagioclase and pyroxene in altered diabase (Sem, Pl and Pyx are the mineral name symbols of clay minerals, plagioclase and pyroxene respectively);

[0070] S2: Based on the classification of altered diabase types, define the factor set and judgment set;

[0071] Furthermore, the factor set and judgment set include:

[0072] Five key indicators, namely, saturated uniaxial compressive strength, cohesion, integrity coefficient, structural surface characteristic parameters, and alteration index, were selected as the factor set;

[0073] Furthermore, the evaluation set defines the grading standards for surrounding rocks, dividing them into Grade I, Grade II, Grade III, Grade IV, and Grade V, with Grade I being the highest grade, and Grade V being divided into two sub-grades, V1 and V2.

[0074] Furthermore, regarding the determination of the factor set and the evaluation set, the saturated uniaxial compressive strength Rc and cohesion c reflecting the mechanical properties of the rock mass are selected as mechanical indicators, the integrity coefficient Kv and structural surface characteristic parameter Jc reflecting the integrity and structural surface characteristics of the rock mass are selected as rock mass structural indicators, and the alteration index, an alteration indicator reflecting the degree of clay alteration, together constitutes an indicator system for fuzzy evaluation of the grade of altered diabase surrounding rock. Among them, the five-level surrounding rock classification method is currently the commonly used surrounding rock classification method. Generally, the surrounding rock is divided into Ⅰ, Ⅱ, Ⅲ, Ⅳ, and Ⅴ. Ⅰ is the highest. The larger the number, the better the nature of the surrounding rock. Because the properties of altered diabase with the same Ⅴ-level surrounding rock are quite different, in order to reflect the difference in the classification of moderately altered and strongly altered rock masses, on the basis of the original five-level surrounding rock classification, the Ⅴ-level surrounding rock is further divided into two subcategories, Ⅴ1 and Ⅴ2;

[0075] Furthermore, a set of various factors that affect the evaluation results of the evaluation object is established, which is called the factor set:

[0076] U={u1,u2,…,u m}

[0077] Furthermore, we build a set of possible judgment results for the judgment object, called the judgment set:

[0078] V={v1,v2,…,vj,…,v n}

[0079] Furthermore, in the factor set, the influence of each factor on the evaluation result is different. The weight ai (i = 1, 2, ... m) reflects the importance of each factor, which is represented by the weight vector of the weight set. The weight vector is obtained by the hierarchical analysis method:

[0080]

[0081] The weight vector should satisfy a1+a2+…+a m =1.

[0082] It should be noted that the present invention is applicable to the determination of the degree of alteration of altered diabase and the quality classification of tunnel surrounding rocks. Further, the present invention is applicable to the study of the degree of alteration of altered rocks formed by thermal fluid and tectonic dynamic alteration and the quality classification of tunnel surrounding rocks.

[0083] S3: Based on the factor set and the judgment set, the judgment matrix is ​​constructed through the hierarchical analysis method, and the weight vector is obtained by solving the eigenvalue and eigenvector;

[0084] Furthermore, S3 includes the following steps:

[0085] Compare each pair of factors in the factor set to assess the impact on the evaluation target object;

[0086] The 1-9 scale is used for quantification, and a 5×5 order judgment matrix E is constructed;

[0087] Using the characteristic root method, solve the matrix equation EW = λ max , solve the maximum eigenvalue λ of the judgment matrix E max The characteristic vector corresponding to the maximum eigenvalue is W = [W1, W2, ..., W n ] T ;

[0088] Based on the feature vector W, a consistency check is performed;

[0089] Based on the consistency test, the obtained eigenvector is the weight vector of the rock mass evaluation factor

[0090] Furthermore, according to the Engineering Rock Mass Classification Standard GB / T 50218-2014 and consulting experts

[0091] Opinions, obtain the value range of the evaluation index for different evaluation levels (Table 1), and then calculate the membership function of each factor corresponding to different evaluation levels according to the index division interval in Table 1 (Table 2)

[0092] Table 1 Evaluation index value interval table

[0093]

[0094] Table 2 Membership function table

[0095]

[0096]

[0097] Furthermore, the determination of the weight vector is mainly carried out using the hierarchical analysis method. The main steps of the hierarchical analysis method include constructing a pairwise comparison judgment matrix, solving the eigenvalues ​​and eigenvectors of the judgment matrix, consistency testing and obtaining the weight vector.

[0098] Furthermore, the judgment matrix is ​​constructed by arbitrarily selecting two elements u in the factor set. i and uj , compare their relative importance to the evaluation results of the evaluation object, use a scale of 1 to 9 to make the evaluation, and use element a ij The larger the value, the better. i Than u j The greater the impact on the judgment result, the greater the j with u i When making comparisons, use the reciprocal 1 / a ij Indicates the comparison result. Use this method to construct an n×n order judgment matrix E;

[0099]

[0100] Furthermore, according to the principle of square root method, we can solve the matrix equation EW = λ max , that is, solving the maximum eigenvalue λ of the judgment matrix E max The characteristic vector corresponding to the maximum eigenvalue is W = [W1, W2, ..., W n ] T The calculation steps are as follows: Where: M i To determine the product of each row of the matrix, (EW) i Represents the i-th element of the vector EW.

[0101] Furthermore, in order to obtain the maximum eigenvalue λ of the judgment matrix E max After finding the eigenvector W corresponding to the maximum eigenvalue, a logical consistency check should be performed. The consistency ratio CR is often used for judgment.

[0102] The expression is as follows:

[0103]

[0104] Where: RI is the average random consistency index. When CR<0.10, the test is qualified. When the test fails (CR≥0.10), the judgment matrix needs to be adjusted and the test continues until the test passes.

[0105] S4: construct a fuzzy evaluation matrix through the fuzzy comprehensive evaluation algorithm, multiply the obtained weight vector with the fuzzy evaluation matrix, calculate the membership degree of each surrounding rock mass in each classification through weighted average operation, and form a fuzzy comprehensive evaluation set;

[0106] Furthermore, for the selected rock mass indicators, since they are all geotechnical characteristic indicators that can be quantitatively described and are continuous influencing factors, the normal distribution function can be selected as its membership function, that is:

[0107]

[0108] Where: x i is the actual value of the i-th evaluation factor, m ij The median value of the j-level interval of the i-th evaluation factor can be taken, and σ is its standard deviation. The calculation formula is:

[0109]

[0110] Where: and are the upper and lower limits of the j-level interval respectively.

[0111] Furthermore, according to the fuzzy comprehensive evaluation principle, the calculated feature vector W is the weight vector of each evaluation factor.

[0112] Furthermore, a fuzzy evaluation matrix is ​​constructed by a fuzzy comprehensive evaluation algorithm, including the following steps:

[0113] The obtained weight vector Applied in fuzzy comprehensive evaluation, the fuzzy evaluation matrix is ​​constructed for each indicator;

[0114] Select normal distribution to construct membership function and determine the membership degree of each factor at each evaluation level;

[0115] The membership degree r of each factor in each evaluation level ij Fill in the fuzzy judgment matrix

[0116] Furthermore, the formula for establishing the fuzzy comprehensive evaluation matrix is ​​expressed as:

[0117]

[0118] Where: r ij The factor u of a certain evaluation object i For the judgment results i The membership degree of . The i-th row R i = {r i1 ,r i2 ,…,r in} is the i-th evaluation factor u i The single factor judgment vector of is usually determined by using the membership function.

[0119] Furthermore, these weights are applied through the fuzzy comprehensive evaluation algorithm, combined with the evaluation matrix R of each indicator (which contains the original membership of the indicator to each evaluation level), and the weighted average operation is performed to obtain the membership b of each surrounding rock mass in each classification. j ;

[0120]

[0121] Among them, a i is the weight value, reflecting the importance of each factor; b j Indicates the evaluation object for v j The degree of membership.

[0122] Furthermore, by the weight vector and fuzzy comprehensive evaluation matrix Perform weighted average synthesis operation (·) to obtain the corresponding fuzzy comprehensive evaluation set:

[0123]

[0124] S5: Based on the membership of each surrounding rock mass in each classification, the maximum membership principle is used to determine the final classification of each rock mass, thus realizing the classification of the quality grade of the altered diabase surrounding rock.

[0125] Furthermore, the maximum membership principle is used to determine the final classification of each rock mass, including: according to the maximum membership principle, the membership b of each surrounding rock mass in each classification is j Find the value b with the highest membership among all the evaluation levels j0 , the corresponding v j This is the final classification of the rock mass.

[0126] Furthermore, finally, according to the maximum membership principle, we can take:

[0127] b j0 =max b j (0≤j≤n)

[0128] The corresponding grade vj is the evaluation result.

[0129] Among all the calculated membership degrees b j (where j ranges from 0 to n), find the largest value and assign it to b j0 In other words, b j0 It represents the highest membership value among all evaluation levels, that is, the maximum membership value of the level that the rock mass most conforms to among all the evaluation levels considered. In the context of fuzzy comprehensive evaluation, this maximum membership principle is often used to determine the final classification of the rock mass, that is, the evaluation level v to which the rock mass is most likely to belong. j Corresponds to b j0 .

[0130] This embodiment also provides a quantitative system for classifying the quality grade of the surrounding rock of an altered diabase tunnel, including:

[0131] The classification module is used to collect diabase with different alteration degrees, analyze the mineralogical characteristics of the collected diabase with different alteration degrees, and classify the altered diabase into types;

[0132] Definition module, based on the classification of altered diabase types, defines factor sets and judgment sets;

[0133] The solution module is used to construct a judgment matrix based on the factor set and the judgment set through the hierarchical analysis method, and obtain the weight vector by solving the eigenvalue and eigenvector;

[0134] The calculation module is used to construct a fuzzy evaluation matrix through a fuzzy comprehensive evaluation algorithm, multiply the obtained weight vector with the fuzzy evaluation matrix, calculate the membership degree of each surrounding rock mass in each classification through weighted average operation, and form a fuzzy comprehensive evaluation set;

[0135] The classification module is used to determine the final classification of each rock mass based on the membership of each surrounding rock mass in each classification and using the maximum membership principle, thereby realizing the classification of the quality grades of the altered diabase surrounding rock.

[0136] Furthermore, it also includes:

[0137] Memory, used to store programs;

[0138] A processor is used to load the program to execute the quantitative method for classifying the quality grade of the surrounding rock of the altered diabase tunnel.

[0139] This embodiment also provides a computer-readable storage medium storing a program, which, when executed by a processor, implements the quantitative method for classifying the quality grade of the surrounding rock of the altered diabase tunnel.

[0140] The storage medium proposed in this embodiment and the quantitative method for classifying the quality grade of altered diabase tunnel surrounding rock proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0141] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ReadOnly, Memory, ROM), random access memory (RandomAccess Memory, RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform the methods of various embodiments of the present invention.

[0142] Example 2

[0143] Reference Figure 2-Figure 3 Tables 3 to 7 are an embodiment of the present invention, which provide a quantitative method for classifying the quality grade of the surrounding rock of an altered diabase tunnel. In order to verify its beneficial effects, scientific demonstration is carried out through specific implementation methods and implementation effects.

[0144] The present embodiment is as follows:

[0145] Step 1: The altered diabase used in this case was obtained from the water diversion tunnel of the Yingliangbao Hydropower Station in Sichuan Province, China. Figure 2 As shown in the figure, the tunnel sampling location and sampling points are determined. Through on-site macroscopic geological surveys, the evaluation indicators such as hammer reaction, rock type, rock structure, and structural surface spacing are investigated. The diabase with different degrees of alteration is qualitatively judged at the macro level, the sampling location is determined, and the altered diabase is sampled first for the next step of mechanical testing and rock mineralogy analysis.

[0146] Step 2: After sampling, firstly, the altered diabase with different alteration degrees was subjected to indoor uniaxial test to obtain the saturated uniaxial compressive strength of the altered diabase with different alteration degrees. At the same time, the XRD quantitative phase composition analysis was performed using the Japanese Rigaku Ultima IV diffractometer. The XRD spectrum of the typical sample is as follows: Figure 3 The mineral composition of altered diabase with different alteration degrees was analyzed, and finally the types and alteration characteristics of altered rocks were divided. Among them, the altered diabase was divided into: micro-altered diabase, cataclastic diabase, cataclastic diabase, diabase breccia, foliated diabase, and mud diabase according to its rock type, representing micro-alteration, weak alteration, moderate alteration, strong alteration, strong alteration, and strong alteration, respectively, as shown in Table 3.

[0147] Table 3 Types and alteration characteristics of altered diabase

[0148]

[0149] Note: Clay mineral content is the sum of kaolinite and chlorite

[0150] Step 3: Based on the classification of altered diabase types, a quantitative indicator representing the degree of alteration of altered diabase, the ks alteration index, was constructed. Representative samples of altered diabase of different types were selected, and the mineral composition of altered diabase of different alteration types was analyzed. The alteration index of altered diabase of different alteration degrees was calculated according to the alteration index formula to quantitatively characterize the degree of alteration, as shown in Table 4.

[0151] Table 4 Mineral composition (XRD analysis) and alteration index of altered diabase

[0152]

[0153] Note: The bold data in the table are average values, and the clay mineral content is the sum of kaolinite and chlorite.

[0154] Step 4: Select the saturated uniaxial compressive strength R c , cohesion c, integrity coefficient K v , structural surface characteristic parameters J c , alteration index k s As the basis for surrounding rock classification, Table 5 shows the surrounding rock data of 25 locations in the diversion tunnel of the Yingliangbao Hydropower Station.

[0155] Table 5 Index values ​​of altered diabase in the diversion tunnel of Yingliangbao Hydropower Station

[0156]

[0157]

[0158] Step 5: Establish a fuzzy rating model for altered diabase surrounding rock classification.

[0159] The main steps of the hierarchical analysis method include constructing a pairwise comparison judgment matrix, solving the eigenvalue and eigenvector of the judgment matrix, consistency test and obtaining the weight vector. The construction method of the judgment matrix is ​​to arbitrarily select two elements u in the factor set. i and u j , compare their relative importance to the evaluation results of the evaluation object, use a scale of 1 to 9 to make the evaluation, and use element a ij The larger the value, the better. i Than u j The greater the impact on the judgment result, the greater the j with u i When making comparisons, use the reciprocal 1 / a ijIndicates the comparison result. This method can be used to construct a 5×5 judgment matrix E:

[0160]

[0161] According to the principle of square root method, solve the matrix equation EW = λ max , that is, solving the maximum eigenvalue λ of the judgment matrix E max The characteristic vector corresponding to the maximum eigenvalue is W = [W1, W2, ..., W n ] T The calculation steps are as follows:

[0162]

[0163] Where: M i To determine the product of each row of the matrix, (EW) i Represents the i-th element of the vector EW.

[0164] In order to obtain the judgment matrix E The maximum eigenvalue λ max After finding the eigenvector W corresponding to the maximum eigenvalue, a logical consistency check should be performed. The consistency ratio CR is often used for judgment. The expression is as follows:

[0165]

[0166] Where: RI is the average random consistency index, and for the fifth-order matrix RI is 1.12. When CR<0.10, the test is passed. When the test fails (CR≥0.10), the judgment matrix needs to be adjusted and the test continues until the test passes.

[0167] Table 6 shows the weight calculation results of the judgment matrix of rock mass indicators. The maximum eigenvalue λ of the judgment matrix max =5.070, the corresponding eigenvector is:

[0168] W=[0.315,0.070,0.330,0.094,0.192]

[0169] Table 6 Judgment matrix weight calculation results

[0170] Judging factors <![CDATA[M i ]]> <![CDATA[W i ]]> <![CDATA[(EW) i ]]> <![CDATA[u1]]> 24.000 0.315 1.888 <![CDATA[u2]]> 0.013 0.070 0.416 <![CDATA[u3]]> 30.000 0.330 1.974 <![CDATA[u4]]> 0.056 0.094 0.561 <![CDATA[u5]]> 2.000 0.192 1.149

[0171] From the consistency test result RI = 0.016 < 0.10, it can be seen that the evaluation matrix meets the consistency test conditions. According to the fuzzy comprehensive evaluation principle, the calculated eigenvector W is the weight vector A of each evaluation factor.

[0172] The surrounding rock of the 2#0+860 tunnel section is taken as a typical research object, and the surrounding rock classification calculation is carried out.

[0173] According to the fuzzy comprehensive evaluation principle, the comprehensive evaluation matrix of the rock mass is first calculated by the membership function, and then the weight vector and the evaluation matrix are calculated using the weighted average operator to obtain the membership degree of the surrounding rock for each classification:

[0174]

[0175] Based on this, according to the maximum membership principle, this surrounding rock is judged to be Class IV surrounding rock, which is consistent with the qualitative surrounding rock classification results based on the actual stability and excavation support conditions on site. The surrounding rock classification results of 25 locations in the diversion tunnel of the Yingliangbao Hydropower Station are shown in Table 7.

[0176] Table 7 Index values ​​of altered diabase and surrounding rock quality grades of the diversion tunnel of the Yingliangbao Hydropower Station

[0177]

[0178] The existing hydropower HC method surrounding rock classification results are compared with the field classification results (Table 8). The existing hydropower HC method uses rock saturated uniaxial compressive strength, rock integrity and structural surface state as basic parameter indicators, groundwater state and main structural surface occurrence as correction indicators, and then uses the summation method to calculate the T value to systematically classify the surrounding rock.

[0179] Table 8 Comparison of surrounding rock classification results

[0180] Hydropower HC method Fuzzy judgment method Matching rate 81.6％ 91.8％

[0181] From the comparison results, it can be seen that the fuzzy comprehensive evaluation method has a higher credibility, so this method is more suitable for the classification of altered diabase surrounding rock system. The calculation results show that the micro-altered diabase is mainly Class II surrounding rock, the fragmented diabase is mainly Class III surrounding rock, the fragmented diabase is all Class IV surrounding rock, the diabase breccia is all Class V1 surrounding rock, and the foliated and muddy diabase is all Class V2 surrounding rock. Therefore, when the saturated uniaxial compressive strength R of the rock mass is measured, c , cohesion c, integrity coefficient K v , structural surface characteristic parameters J c and alteration index k s On this basis, the fuzzy comprehensive evaluation method can be used to dynamically track and evaluate the altered diabase surrounding rock, and then put forward targeted treatment measures and support suggestions.

[0182] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A quantitative method for classifying the quality of the surrounding rock of an altered diabase tunnel, characterized in that: include: Collect diabase with different degrees of alteration, analyze the mineralogical characteristics of the collected diabase with different degrees of alteration, and classify the altered diabase into types; Based on the classification of altered diabase types, define factor sets and judgment sets; Based on the factor set and the judgment set, the judgment matrix is ​​constructed through the hierarchical analysis method, and the weight vector is obtained by solving the eigenvalue and eigenvector; The fuzzy evaluation matrix is ​​constructed by the fuzzy comprehensive evaluation algorithm, the weight vector obtained is multiplied by the fuzzy evaluation matrix, and the membership degree of each surrounding rock mass in each classification is calculated by weighted average operation to form a fuzzy comprehensive evaluation set; Based on the membership of each surrounding rock mass in each classification, the maximum membership principle is used to determine the final classification of each rock mass, thus realizing the classification of the quality grade of the altered diabase surrounding rock.

2. The quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 1 is characterized by: The factor set and judgment set include: Five key indicators, namely, saturated uniaxial compressive strength, cohesion, integrity coefficient, structural surface characteristic parameters, and alteration index, were selected as the factor set; The evaluation set defines the classification standard of surrounding rock, and divides surrounding rock into grade I, grade II, grade III, grade IV, and grade V, with grade I being the highest grade, and grade V surrounding rock being divided into two sub-grades, V1 and V2.

3. The quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 2 is characterized by: The calculation formula of the alteration index is expressed as: Among them, ks is the alteration index, x Sem 、x Pl 、x Pyx They are the percentage of clay minerals, plagioclase and pyroxene in altered diabase respectively.

4. The quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 3 is characterized by: The construction of the judgment matrix and obtaining the weight vector by solving the eigenvalue and the eigenvector include the following steps: Compare each pair of factors in the factor set to assess the impact on the evaluation target object; The 1-9 scale is used for quantification, and a 5×5 order judgment matrix E is constructed; Using the characteristic root method, solve the matrix equation EW = λ max , solve the maximum eigenvalue λ of the judgment matrix E max The characteristic vector corresponding to the maximum eigenvalue is W = [W1, W2, ..., W n ] T ; Based on the feature vector W, a consistency check is performed; Based on the consistency test, the obtained eigenvector is the weight vector A of the rock mass evaluation factors.

5. The quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 1 is characterized by: The method of constructing a fuzzy evaluation matrix by using a fuzzy comprehensive evaluation algorithm comprises the following steps: The obtained weight vector Applied in fuzzy comprehensive evaluation, the fuzzy evaluation matrix is ​​constructed for each indicator; Select normal distribution to construct membership function and determine the membership degree of each factor at each evaluation level; The membership degree r of each factor in each evaluation level ij Fill in the fuzzy judgment matrix 6. The quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 5 is characterized by: The membership degree of each surrounding rock mass in each classification is expressed as: Among them, m is the total number of evaluation indicators, a i is the weight value.

7. The quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 6 is characterized by: The method of using the maximum membership principle to determine the final classification of each rock mass includes: according to the maximum membership principle, the membership b of each surrounding rock mass in each classification is j Find the value b with the highest membership among all the evaluation levels j0 , b j0 The corresponding v j This is the final classification of the rock mass.

8. A system based on the quantitative method for grading the quality of the surrounding rock of the altered diabase tunnel according to claim 1, characterized in that: The classification module is used to collect diabase with different alteration degrees, analyze the mineralogical characteristics of the collected diabase with different alteration degrees, and classify the altered diabase into types; Definition module, based on the classification of altered diabase types, defines factor sets and judgment sets; The solution module is used to construct a judgment matrix based on the factor set and the judgment set through the hierarchical analysis method, and obtain the weight vector by solving the eigenvalue and eigenvector; The calculation module is used to construct a fuzzy evaluation matrix through a fuzzy comprehensive evaluation algorithm, multiply the obtained weight vector with the fuzzy evaluation matrix, calculate the membership degree of each surrounding rock mass in each classification through weighted average operation, and form a fuzzy comprehensive evaluation set; The classification module is used to determine the final classification of each rock mass based on the membership of each surrounding rock mass in each classification and using the maximum membership principle, thereby realizing the classification of the quality grades of the altered diabase surrounding rock.

9. An electronic device, characterized in that: include: Memory, used to store programs; A processor, used to load the program to execute the steps of the quantitative method for classifying the quality grade of the surrounding rock of the altered diabase tunnel as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a program, characterized in that: When the program is executed by a processor, the steps of the quantitative method for classifying the quality grade of the surrounding rock of an altered diabase tunnel as described in any one of claims 1 to 7 are implemented.

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