Rock mass integrity evaluation method based on post-explosion rock mass measurement

Abstract

The invention discloses a rock mass integrity evaluation method based on post-explosion rock mass measurement, which comprises the following steps: calculating a fracture development condition according to a characteristic parameter M of a rock mass, and establishing a rock mass integrity evaluation standard according to the fracture development condition; drilling blast holes in the to-be-evaluated area according to the blasting design, and detonating after charging; for a rock block generated after detonation, identifying to obtain a plane geometric contour of the rock block; calculating the volume of each rock according to the obtained plane contour of the rock; and according to the calculation result of the rock volume, obtaining a rock characteristic parameter M, and evaluating the rock integrity of the to-be-evaluated region based on the calculated characteristic parameter M and a rock integrity evaluation standard. The rock mass integrity of the explosion area is evaluated from the angle of three-dimensional distribution of the structural surface, and the defect that only points or surfaces are considered in an existing rock mass integrity evaluation system is effectively overcome.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering geological survey, and in particular relates to a rock mass integrity evaluation method based on post-blasting rock block measurement. Background Art

[0002] Rock mass quality evaluation and classification has always been an important topic of common concern to surveyors, designers, construction and scientific researchers. The quality of rock mass depends on the intrinsic factors that constitute the structural characteristics of the rock mass, and rock mass integrity is one of the controlling factors. How to scientifically and conveniently evaluate the integrity of engineering rock mass is of great significance to rock engineering construction. At present, there are many indicators used to characterize rock mass integrity at home and abroad, and there are three main methods for obtaining these indicators: ① Elastic wave test method, the evaluation indicators based on this method are rock mass integrity coefficient (rock mass cracking coefficient) K v etc.; ② Core drilling method, based on which the evaluation indicators include rock quality index RQD, number of cracks per unit core, etc.; ③ Structural surface statistics method, based on which the evaluation indicators include rock volume joint number J v , average joint spacing d p Etc. These evaluation methods have their own advantages and disadvantages, and most of the evaluation indicators only reflect the integrity of the rock mass from one aspect. For example, the elastic wave test method mostly uses the drilling test method for measurement, which has a high test cost and can only reflect the integrity of the rock mass at the drilling location. The test results are greatly affected by the location of the drilling hole. The core drilling method has the same disadvantages as the elastic wave test method, and there is controversy over the RQD concept itself. The structural surface statistics method is very convenient and fast in application, but the evaluation results of this method can only reflect the geometric development characteristics of the structural surface on the surface of the rock mass, but cannot reflect the degree of development of the structural surface inside the rock mass. Summary of the invention

[0003] The purpose of the present invention is to address the deficiencies of the prior art and provide a rock integrity evaluation method based on post-blasting rock block measurement. This method evaluates the rock integrity of the blasting area from the perspective of the three-dimensional distribution of structural surfaces, effectively avoiding the shortcomings of the existing rock integrity evaluation system that only considers points or surfaces.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A rock mass integrity evaluation method based on post-blasting rock block measurement comprises the following steps:

[0006] Step 1: Calculate the fracture development according to the characteristic parameter M of the rock mass, and establish the rock mass integrity evaluation standard based on it;

[0007] Step 2: Drill blastholes in the area to be evaluated according to the blasting design, load explosives and detonate;

[0008] Step 3: for the rock blocks generated after detonation, identify and obtain the plane geometric contour of the rock blocks;

[0009] Step 4, calculating the volume of each rock block according to the obtained rock block plane contour;

[0010] Step 5: Obtain the rock block characteristic parameter M according to the calculation result of the rock block volume, and evaluate the rock integrity of the area to be evaluated based on the calculated characteristic parameter M and the rock integrity evaluation standard.

[0011] Furthermore, the method for establishing the rock mass evaluation standard in step 1 is: taking the characteristic parameter M of the rock block as the side length of a cube per unit volume to calculate the number of cracks, and determining the interval division of the characteristic parameter M for rock mass integrity evaluation and its corresponding degree of integrity according to the number of cracks.

[0012] Furthermore, in step 1, the characteristic parameter M is divided into five intervals: greater than 0.5 m, 0.25-0.5 m, 0.125-0.25 m, 0.083-0.125 m, and less than or equal to 0.083 m, and the corresponding rock integrity is: complete, relatively complete, relatively broken, broken, and extremely broken.

[0013] Furthermore, the method for calculating the volume of the rock block in step 4 is: the volume obtained by rotating the plane geometric outline of the rock block by 180° along its long axis.

[0014] Furthermore, the average volume of the rock blocks with a major axis size greater than 50 mm is taken as the characteristic parameter M of the rock blocks.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention obtains the average volume of the rock block by counting the products of blasting rock blocks, and obtains the number of rock cracks in three directions under the condition of the average volume under the concept that the rock block is evenly cut in three dimensions, and obtains each evaluation interval of the characteristic parameter M for evaluating the rock integrity of the blasting area by the number of cracks, and the rock integrity can be evaluated by only calculating the characteristic parameter M of the rock block after detonation, which effectively avoids the shortcomings of the existing rock integrity evaluation method that can only consider the distribution of cracks on the line or surface, and ignores the influence of the structural surface not exposed on the rock surface, reflects the crack distribution from an overall perspective, and makes a more reasonable evaluation of the rock integrity. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a flow chart of a rock mass integrity evaluation method based on post-blasting rock block measurement according to an embodiment of the present invention;

[0017] Figure 2 This is a diagram showing the results of identifying the plane geometric contour of a rock block according to an embodiment of the present invention;

[0018] Figure 3Schematic diagram of the rock volume calculation method according to the present invention. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0021] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited thereto.

[0022] like Figure 1 As shown, the embodiment of the present invention discloses a rock mass integrity evaluation method based on post-blasting rock block measurement, comprising the following steps:

[0023] Step 1: Calculate the fracture development according to the rock block characteristic parameter M to establish the rock mass integrity evaluation standard;

[0024] Specifically, the characteristic parameter M of the rock block is taken as the side length of a cube per unit volume to calculate the number of cracks, and the interval division of the characteristic parameter M for rock mass integrity evaluation is determined according to the number of cracks;

[0025] Assume that the characteristic parameter of the rock block is 0.5m; then the unit volume of the rock block is composed of 8 cubic rock blocks with a side length of 0.5m, and the number of cracks J v Calculation, since it can only be observed from a single face, then J v =2, its integrity is "intact", and so on, the interval ranges of the characteristic parameter M of relatively intact, relatively broken, broken and extremely broken are obtained respectively; thus, the rock integrity evaluation table is obtained as shown in Table 1 below.

[0026] Table 1 Rock mass integrity evaluation table

[0027]

[0028] Step 2: Drill blast holes in a certain blasting area, charge them and detonate them to obtain a series of rock blocks;

[0029] Step 3: Use image recognition software such as WipFrag to identify the plane geometric contours of each rock block after blasting, such as Figure 2 As shown;

[0030] Step 4: Calculate the volume of each rock block based on the obtained rock block plane contour. The method for calculating the rock block volume is: the volume obtained by rotating the plane geometric contour of the rock block along its long axis for one circle, as shown in the following example: Figure 3 As shown;

[0031] Step 5: Obtain the rock block characteristic parameter M based on the calculated rock block volume, and evaluate the rock integrity of the area to be evaluated based on the calculated characteristic parameter M and the rock integrity evaluation standard.

[0032] In this embodiment, the average volume of rock blocks with a major axis AB greater than 50 mm is calculated to obtain a characteristic parameter M; and then the integrity of the rock mass in the area to be evaluated is evaluated based on the interval of the calculated characteristic parameter M and combined with the above Table 1.

[0033] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of the specification of the present invention should be included in the protection scope of the present invention.

Claims

1. A rock mass integrity evaluation method based on post-blasting rock block measurement, characterized in that: The following steps are involved: Step 1: Calculate the fracture development according to the characteristic parameter M of the rock mass, and establish the rock mass integrity evaluation standard based on it; Step 2: Drill blastholes in the area to be evaluated according to the blasting design, load explosives and detonate; Step 3: for the rock blocks generated after detonation, identify and obtain the plane geometric contour of the rock blocks; Step 4, calculating the volume of each rock block according to the obtained rock block plane contour; Step 5: Obtain the rock block characteristic parameter M according to the calculation result of the rock block volume, and evaluate the rock integrity of the area to be evaluated based on the calculated characteristic parameter M and the rock integrity evaluation standard.

2. The rock mass integrity evaluation method based on post-blasting rock block measurement according to claim 1 is characterized in that: The method for establishing the rock mass evaluation standard in step 1 is: taking the characteristic parameter M of the rock block as the side length of a cube per unit volume to calculate the number of cracks, and determining the interval division of the characteristic parameter M for rock mass integrity evaluation and its corresponding degree of integrity according to the number of cracks.

3. The rock mass integrity evaluation standard based on post-blasting rock mass measurement according to claim 2 is characterized in that: In step 1, the characteristic parameter M is divided into five intervals: greater than 0.5 m, 0.25-0.5 m, 0.125-0.25 m, 0.083-0.125 m, and less than or equal to 0.083 m, and the corresponding rock integrity is complete, relatively complete, relatively broken, broken, and extremely broken.

4. The rock mass integrity evaluation method based on post-blasting rock block measurement according to claim 1 is characterized in that: The method for calculating the volume of the rock block in step 4 is: the volume obtained by rotating the plane geometric outline of the rock block 180° along its long axis.

5. The rock mass integrity evaluation method based on post-blasting rock block measurement according to claim 1 is characterized in that: The mean volume of the rock blocks with the major axis size greater than 50 mm is taken as the characteristic parameter M of the rock blocks.

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