KR101537955B1 - Evaluation method for rock cleavage using distribution characteristics of volumetric strain curve for granite - Google Patents

Abstract

The present invention relates to a method for evaluating a texture using distribution characteristics of a volumetric strain curve of granite comprising: a rock block collecting step to collect a square rock block from granite; a rock block surface cutting step to cut a surface of the rock block in a direction parallel to three texture surfaces; a rock block dividing step to divide the rock block into a plurality of square rock samples; a core specimen manufacturing step to manufacture each core specimen in a direction perpendicular to three texture surfaces in the rock sample; a stress applying step to apply stress with respect to the core specimens; and a texture quantitative evaluation step to obtain a stress-volumetric strain curve by calculating volumetric strain (ε_v) for each texture by measuring dynamic response according to the stress applied to the core specimens, to divide a rock fracturing step through the stress-volumetric strain curve into four steps of strength sections (I, II, III, and IV), to divide a linear section having a form of a straight line into IV-2 section in the stress-volumetric strain curve of IV step among four steps of strength sections, to analyze distribution characteristics of the stress -volumetric strain curve in the corresponding IV-2 section, and to evaluate relative strength with respect to three texture surfaces.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of evaluating a texture of a granite,

The present invention relates to a resolution evaluation method using the distribution characteristics of the volume strain curve of granite.

In Korea, granite quarry is quarried by using rock cleavage, which is easy to rock splitting inside the rocks. The development of resolution is a common phenomenon in all granitic rocks in Korea and abroad. Especially, the orientation direction of vertical grains is different locally in relation to the generation time of granite and the generation time of microcracks inside granite.

The relative ease of the granite is generally in the order of rift> 2 grain> 3 hardway, and the three types of quarries generally form a mutual vertical relationship . In terms of stone structure in English, the term surface structure corresponding to 1, 2 and 3 is referred to as a rift plane, a grain plane and a hardway plane, Are mutually orthogonal.

The directionality of these quarry facies plays a major role in determining the quarry direction in the unit quarry and also has a great effect on the quarrying error rate in the case of explosive blasting for standard quarries. Therefore, the ability to discern these vertical grains is particularly recognized in granite rocks. The difference in the density of horizontal and vertical microcracks (striae) in each stalagmite indicates the relative separability of stalactites in the rocks.

In the quarrying area, since the quarry surface of the rock is formed differently by the actual quarry, the direction of the first quarry can not be commonly applied, and since the direction of the first quarry is empirically found in most quarries, have.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and its object is to derive the difference of various distribution characteristics in the volume strain curve for each specimen derived through the test and measurement of the strength and strain rate in sec , And a method of evaluating three quarried surfaces.

On the other hand, the distribution of microcracks distributed in the rock samples is ambiguous and is often difficult to be visually confirmed. It is considered that the characteristic of the volume strain curve for the texture under the same stress condition is well representative of the typical distribution characteristic of the micro crack present in the rock sample. It is compared with the evaluation result of the micro crack through the conventional flake photograph, and is in contrast to the characteristic of the volume strain curve. The separation of the three quarry facies from the granite rocks is in the order of rift plane> grain plane> 3 (hardway plane). In other words, it can contribute to the reference data such as direction setting of the quarry surface in the early stage of development of granite rocks, and further control of the amount of explosive powder in the parallel direction of three sides.

According to the present invention, there is provided a method for recovering granite from a granite; A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces; A rock block dividing step of dividing the rock block into a plurality of square rock samples; A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen; A stress applying step of applying stress to the core specimens; And a mechanical stress response to the core specimens is measured and a volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four steps The linear section with the shape of a straight line in the stress-volumetric strain curve of step IV is divided into sections Ⅳ-2 of the strength sections of the four steps, and the section Ⅳ-2 section is divided into sections Ⅰ, Ⅱ, Ⅲ and Ⅳ. A quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the stress-volume strain curves; The present invention provides a method of evaluating a resolution using a distribution characteristic of a volume strain curve of a granite.

Preferably, in the quantitative evaluation step of the texture, the relative intensity of the texture is evaluated to be lower as the position where the section of the line IV-2, which is a linear section in the shape of a straight line in the stress-strain curve, is located on the right side do.

Preferably, in the above-resolution quantitative assessment phase, the stress-vertical one extending in the X-axis direction from the initial point (C) line in the interval Ⅳ-2 in volume strain curve and corresponding to the end points of σ ₁ ^c of Ⅰ step The moving path of the intersection A 'between the intersection A' with the horizontal line is analyzed and the relative strength of the intersection A 'is determined to be lower than that of the element located to the left of the initial point A on the basis of the initial point A of the intersection A' .

Preferably, in the quantitative evaluation step of the texture, the initial point (C) of the section IV-2 and the end point (B) of the step II are extended from the stress-strain curve to connect the point (G) The angle? Of one line (CBG) is analyzed and the relative strength of the curve is evaluated to be lower as the angle? Is smaller.

Preferably, in the quantitative evaluation step of the texture, a straight line (C-C ') extending the initial point (C) of the section IV-2 in the stress-strain curve and connecting a point (C' (CBG) connecting the initial point C of the section IV-2 and the end point B of the stage II to connect the point G that meets the X axis is obtained, and the straight line CB CBG, C'-G) obtained after the straight line C'-G connecting the C 'and G of the X-axis divided by the three straight lines C-C', CBG and C'- (? CC'G) is analyzed, and the relative strength of the grains is evaluated to be lower as the area ratio is larger.

Preferably, in the quantitative evaluation step of the texture, a straight line CF connecting the point F, which extends in the vertical direction at the initial point C of the section IV-2 in the section of the stress-volume strain curve and meets the volume strain curve, (E) and the initial point (C) of the section IV-2 are obtained by obtaining a straight line CE connecting the initial point C of the section IV-2 and the inflection point E of the stage III and IV, The area EF of the triangle CAF captured by the three straight lines CF, CE and EF is analyzed after the straight line EF connecting the points F intersecting with the volume strain curve is extended in the vertical direction, And the relative strength of the texture is evaluated to be lower as the area becomes wider.

Preferably, the area ratio of the triangle (? CEF) captured by the three straight lines (C-F, C-E, and E-F) is analyzed and the relative strength of the triangle is evaluated to be lower as the area ratio is larger.

Preferably, in the quantitative evaluation step of the texture, points (I, II, III, IV-1, and IV-2) on the volume strain curve on the stress-volume strain curve at the intersection (0) (L ₁ , L ₂ , L ₃ , L ₄ and L ₅ ) of _five straight lines OA, 0B, 0E, 0C and 0D connected to each other were measured and analyzed. As the length of five straight lines was longer, Is evaluated as low.

The distributional characteristics of the volume strain curves for grains under the same stress conditions for the granites that are quarried in one rocky mountain are well representative of the typical distribution characteristics of the microcracks present in the rock samples. The evaluation results of the micro cracks through the conventional flake photographs were compared with those of the result of the analysis. From these contrasts, the typical distribution characteristics of the volume strain curves representing the differences between the three surfaces are derived. In conclusion, it is possible to recognize three surfaces in advance by using the characteristics derived from the volume strain curves without going through the process of evaluation of micro cracks, which requires much time and effort.

In the early stage of the development of the granite rocks, the distribution characteristics of the volume strain curves for the rock samples are derived and can contribute to a more accurate recognition of the mutually orthogonal six directions of grain in three aspects.

In other words, the distribution characteristics of the micro cracks and the distribution of the volume strain curves, which have been previously described in relation to the three quarries forming the perpendicular to each other in the granite quarry, A clear evaluation can be made.

Prior to the analysis of fine cracks using the flakes, the distribution characteristics of the volume strain curves for the specimens of the international standard are derived, and the distinction between the three quarried surfaces can be recognized in advance.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart showing a method of evaluating a settlement using the distribution characteristics of a volume strain curve of granite according to the present invention. FIG.
FIG. 2 is a view showing a process of sampling a rock sample and preparing a specimen for an indoor mechanics test; FIG.
3 (a) and 3 (b) are enlarged photographs of thin flakes fabricated in parallel to the first, second, and third surfaces, respectively, and the sketch results of microcracks.
Fig. 4 is a schematic view showing various physical quantities of microcracks (texture) in six directions. Fig.
Figure 5 shows the differential and differential strain of section IV-2 through the acquisition of the linear section IV-2 in the axial stress-volume strain curve (G-1 specimen) Fig.
FIG. 6 is a graph showing the differential stress and differential strain of the linear section IV-2 in the axial stress-volume strain curve obtained under uniaxial compression, and the changes of the angle, the triangle CC'G, and the CEF.
FIG. 7 is a diagram showing changes in the angle, the triangle CC'G, and the CEF, the differential strain and the differential stress, which are obtained from the volume strain curves of the respective specimens for the respective surfaces.
8 is a graph showing changes in the lengths (L ₁ to L ₅ ) and angles (α ₁ to α ₅ ) between the origin and the point on the volume strain curve in the axial stress-volume strain curve (G-1 specimen) under uniaxial compression; .
9 is a graph showing the anisotropy coefficient, the angles (alpha ₁ to alpha ₅ ), and the anisotropy coefficient changes of the length (L ₁ to L ₅ ) and the length obtained from the volume strain curves (Fig. 6) .

Hereinafter, a method of evaluating a texture using the distribution characteristics of the volume strain curve of the granite according to the present invention will be described in detail with reference to the accompanying drawings.

The present invention relates to a quantitative evaluation method of the texture developed in rocks, especially granites, and quantitatively characterizes the microstructures of microstructures (microcracks) primarily through enlarged photographs of the flakes. Secondly, the fracture process of the 4th step (Ⅰ ~ Ⅳ) is derived on the volume strain rate (ε _v ) curve. In other words, the strength in four steps (σ ₁ ^c , σ ₁ ⁱ , σ ₁ ⁱⁱ And? ₁ ^f ) were tested and measured.

In other words, the distribution of microcracks associated with the three quarries forming mutual verticals in the granite quarry and the volume deformation rates indicating the porosity (volume) of the crystals are compared with each other, and the volume concept for horizontal and vertical grains forming these three quarries Of the total.

On the other hand, the volumetric strain rate of the three dimensional volume concept (porosity) of the horizontal and vertical grains was derived using the international standard specification (NX size), and the distribution of the two - dimensional microcracks derived from the enlarged photograph of the flakes was compared. This comprehensive contrast gives a clearer assessment of the three quarries and the results of the six directions presented in the diagram (see Figures 3 and 4).

In connection with the distribution of microcracks (see Figs. 3 and 4) which have been identified above, the distribution characteristics of the three quarries and the volume strain curves, which form mutual verticals in the granite quarry, are compared. This mutual contrast provides an approach to more accurate recognition of the unique characteristics of the three quarries. The rocks were granite in Geochang area and Hapcheon area.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flowchart showing a method of evaluating a settlement using the distribution characteristic of a volume strain curve of granite according to the present invention. FIG.

1. Rock block extraction step ( S110 )

The rock blocks to be used for the samples were collected from Jurassic Granite (Gahang granite, G: G) of Sangpuri (Gyeongnam), Gyeongnam Province. Geochang granite is a Jurassic granite with inclusions of Precambrian semi-metamorphic gneiss and biotite gneiss. This rock is greyish white, is a neutral villa of isoplasma, and the size of quartz and feldspar is 2 ~ 6mm. The sampling depth of the rock samples is about 20m. The mode composition (vol.%) Of the main constituent minerals was 31.3% in quartz, 39.5% in plagiarism, 9.8% in quartzite, 9.6% in feldspar, 5.7% in puddite and 2.9% in biotite Is confirmed. This rock belongs to biotite granite in classification. In the schematic diagram showing the relationship between the three colors, the first surface forms a horizontal surface, the second surface forms a vertical surface, and the third surface forms a vertical surface (see FIG. 2 (a)).

Samples were collected from Jurassic granite (Hwacheon granite, specimen: H) of Ugokgori (Shinhwa statue), Hacchun County, Kyungnam Province. Hapcheon granite is intruded by Precambrian microgmatite gneiss, which is covered with sediments of Cretaceous sediments. These rocks are light gray and are composed of coarse granite rocks with a grain size of 2 to 9 mm. The sampling depth of the rock samples is about 17m. The mode composition (vol.%) Of the main constituent minerals was 30.5%, 40.4%, 14.4%, 8.4%, 12.1%, 5.2% and 2.6%, respectively, in the quartz, apatite and apatite This amount is confirmed. This rock belongs to biotite granite in classification.

A square rock block of about 1.2 m in size is obtained in parallel with the first, second and third surfaces of the two stalagmites (see FIG. 2 (a)). A stone block of about 35 cm in size was obtained from a square block of about 1.2 m in size, which was parallel to the first, second, and third sides of the rocks (see FIG. 2 b).

2. Stone block surface cutting step ( S120 )

For the sampled rock block, the rock surface is cut and flattened in a direction parallel to the three quarry surfaces using a large rock cutting saw (see Fig. 2c).

3. Rock block partitioning step ( S130 )

The rock blocks whose surfaces were cut in a direction parallel to the three quarry surfaces were divided into a plurality of square rock samples (see Fig. 2d). The rock samples thus divided are easy to produce specimens and slabs in the room.

4. Specification  Production stage ( S140 )

NX - sized cores were obtained by working in the vertical direction on the first, second, and third sides of the divided rock samples, respectively. The dimensions of the NX core specimen for the room mechanics test are 5.4 cm in diameter and 10.8 cm in length. NX-sized specimens for measuring the strength, strain, and elapsed time in four steps were made perpendicular to the first, second, and third faces, respectively, and named as -1, -2, and -3 specimens, respectively .

Here, -1 means face 1, -2 means face 2, and -3 means face perpendicular to face 3 (see e in FIG. 2).

Preferably, the square rock samples sampled in the sampling step of the rock sample are taken with their mutually orthogonal lift surfaces, grain surfaces and hardway surfaces on the outer surface, and on the lift surface, grain surfaces and hardway surfaces Thereby producing orthogonal specimens. The rock samples are Jurassic granite (Geochang granite, G) distributed in Sangcheong-ri, Gyeongnam Province and Jurassic granite (Hacchae granite, H) distributed in Ugok-ri, Gyeongnam.

5. Observation of microcracks

In granite, two mutually orthogonal structures (microcracks) can be measured on the flakes produced parallel to the three-way quarry. Some of the sketch results for micro-cracks and an enlarged picture of the lamellae of geochang and Hapcheon granite are shown in Figs. 3 (a) and 3 (b), respectively.

As shown in the schematic diagram showing the correlation between the quarry surface and the microcracks shown in FIG. 4, the grain 1 and the hardway 2 in the flakes parallel to the first surface and the hardway 2 in the flakes parallel to the first surface, Microcracks of grain 2 and rift 2 can be measured in rift 1, hardway 1 and lamella parallel to plane 3, respectively. The length, average length and density of the microcracks associated with the six directions presented in the resolution diagram are shown in FIG.

On the other hand, the frequency, average length and density of the microcracks in the quartz and feldspar were calculated by the irradiation method, and the characteristics of the microcracks were determined by mechanically connecting the microcracks in the six directions shown in FIG. Analyze the characteristics. That is, the correlation between the various quantitative discriminating factors and the density of the microcracks discussed above.

(N), total length (L _t ), average length (L _m ), and density (ρ) of cracks are the same as those of lifts>grain> hardwares . As a result of calculating the average values of the two directions of the respective surfaces of the fine cracks, the average values of the grains of the grains 1 + grain (grains 1 + 2) 2)> (hardway 1 + hardway 2) in order of severity. The result of this analysis is an objective setting criterion for -1, -2, -3 specimens.

Direction of
rock cleavage N
L _t
(mm) L _m
(mm) ρ
Rift 1 + Rift 2/2 37 88.8 2.80 0.22 Grain 1 + Grain 2/2 23 42.9 2.17 0.08 Hardway 1 + Hardway 2/2 9 16.4 1.96 0.02

Table 1 shows the average values of N, L _t , L _m and ρ for geochemical granite.

Direction of
rock cleavage N
L _t
(mm) L _m
(mm) ρ
Rift 1 + Rift 2/2 40.5 91.4 2.34 0.17 Grain 1 + Grain 2/2 19.0 47.8 2.31 0.08 Hardway 1 + Hardway 2/2 7.5 14.3 2.02 0.03

Table 2 shows the average values of N, L _t , L _m and ρ for Hwacheon granite.

The sum of the two vertical densities (FIG. 4) arranged in parallel with the load during the uniaxial compression test can be summarized as shown in Table 3 for each specimen. That is, -1 <-2 <-3.

Rock name Sample No. Two sets of micro-cracks arranged vertically Sum of density (rho) Geochang
granite
(G) G-1 Grain 2 + Hadway 1 0.08 0.66 G-2 Rift 2 + Hadway 2 0.19 G-3 Rift 1 + Grain 2 0.39 Hapcheon
granite
(H) H-1 Grain 2 + Hadway 1 0.07 0.54 H-2 Rift 2 + Hadway 2 0.21 H-3 Rift 1 + Grain 2 0.26

Table 3 shows two sets of microcracks arranged horizontally with load during uniaxial compression (see Fig. 4).

6. Stress application, step strength and Strain rate  Measuring step ( S150 )

The compressive strength meter used for the measurement of the strain rate and the required time (sec) according to the continuous stress (strength) applied to the specimen was a servo bulb type automatic capacity measuring device having a compression capacity of 160 tons of MTS (Material Testing System) Control system. The measured value is automatically recorded by the A / D converter attached to the computer. The stroke must be controlled in the destructive test. In this test, the speed of the upward stroke of the stress applied is determined to be 0.1 mm / min. Respectively.

The uniaxial compressive strength and strain rate were measured using a displacement transducer for 20 mm (KYOWA, DF20D), an extensometer (MTS, Model 1632.12c), a dynamic strain amplifier (KYOWA, DMP-G), XY ₁ Y ₂ recorder (WATANABE, WX4302) Respectively. On the other hand, the stress, axial strain, ε _a , lateral strain (εl), and elapsed time in seconds are automatically recorded in the test system. The test was conducted by Korea Institute of Geoscience and Mineral Resources. The volumetric strain (ε _v ) was calculated from the following equation (1), where ε _a is the tensile strain of the NX core and ε _l is the transverse strain of the NX core. have.

The axial strain, transverse strain, and volumetric strain rate of each continuous stress stage can be summarized as shown in Table 4 of Geochang granite.

Stress
(kg / cm ² ) G-1 G-2 G-3 ε _a (-) ε _l (+) ε _v (-) ε _a (-) ε _l (+) ε _v (-) ε _a (-) ε _l (+) ε _v (-) 50 3364 76 3209 1483 37 1406 375 0 374 100 3987 87 3812 1863 58 1746 1179 5 1168 200 4657 114 4428 2311 95 2119 1716 24 1666 300 5134 153 4827 2777 152 2471 2206 66 2072 400 5578 209 5159 3050 197 2654 2593 112 2368 500 5930 267 5394 3343 251 2838 2973 168 2636 600 6169 309 5548 3639 314 3010 3346 230 2885 700 6439 373 5745 3959 383 3191 3671 292 3086 800 6813 446 5923 4198 445 3307 3922 351 3219 900 7083 524 6033 4498 535 3427 4160 414 3331 1000 7335 595 6142 4743 616 3509 4474 501 3470 1100 7589 683 6221 4994 703 3587 4798 608 3581 1200 7831 779 6272 5241 800 3642 5060 718 3623 1300 8074 885 6301 5493 915 3662 5321 865 3590 1400 8300 1009 6279 5801 1077 3646 5663 1777 2109 1500 8528 1157 6213 6042 1238 3565 6004 3964 +1925 1587 6131 6355 +6579 1600 8763 1344 6073 3284 1460 3362 1700 9006 1595 5815 6531 1789 2951 1800 1941 5380 6795 2338 2117 1887 7012 3095 822 1900 2650 4261 2000 9888 4092 1701 2048 10132 8118 +6104

Table 4 shows the values of axial, transverse and volume strain (x10 ^-6 ) of geomorphic granite (G) against stress.

7 Quantitative Evaluation Step (S160)

7-1 Stress- Volume strain rate  4 steps of curve

In the stress - volumetric strain curves, the progress of the fracture process in four stages is more clear than the axial strain and transverse strain curves.

The criteria for the rock fracture process on the stress-volumetric strain curve are as follows. (Ⅱ), which is an almost constant rate of increase (Ⅱ), the inflection point is formed, and the curved line is inverted to cause rapid volumetric expansion. And step 3 is divided into step 3.

      (Ⅲ), which is opened due to vertical gravity due to load increase (Ⅲ), more increased load (Ⅲ) (Ⅳ) until the unstable crack is propagated and destroyed by the cracks.

That is Ⅰ step (0≤σ≤ ₁ ^c: less strength Ⅰ) are sections showing a volumetric strain (ε _v ^o) of the horizontal connection (wire gap) having a rock, Ⅱ step (σ ₁ ^c ₁ ⁱ ≤σ≤σ : less strength ⅱ) is a section, stage ⅲ of elastic properties (σ ₁ ⁱ ₁ ⁱⁱ ≤σ≤σ: less strength ⅲ) is the section is broken by the tensile stress taking place as the section being perpendicular to the connection is open, ⅳ step ^{_{(σ 1 ii ≤σ≤σ 1 f,}} σ 1 f: less ⅳ strength (breaking strength)) may take place as a shear fracture interval. The intensity for each step is σ ₁ ^c , σ ₁ ⁱ , σ ₁ ⁱⁱ And? ₁ ^f , respectively (see FIG. 5). The stress-strain curves of Geochang and Hapcheon granite thus obtained are shown in Fig.

7-2 Setting of the section IV-2 in the stress-volume strain curve

In step IV of the volume strain curves, the linear strain line cd can be obtained after obtaining a linear section having a straight line shape (section IV-2). The setting criterion of the section IV-2 is as follows (see FIG. 5).

The axial strain and transverse strain curves show a curve shape in step IV, and the setting of the linear section is ambiguous. However, in the volume strain curve, it is possible to set an objective linear interval. These linear segments are common to all of the six specimens and serve as an objective basis for subdividing step IV into three segments, focusing on segment IV-2. That is, the right side section can be divided into Ⅳ-1 and the left side section can be divided into Ⅳ-3 with respect to section Ⅳ-2.

In other words, through the volume strain curve, the criteria for subdividing the rock destruction process in step IV into three sections are as follows. (IV-1), which has an inflection point with the boundary of the linear section (section IV-2) as a boundary, has a sharp curve shape, that is, the volume expansion phenomenon And a section IV-3 leading to destruction.

In addition, it is possible to divide the section IV-1 before the linear section according to the stress increase in the step IV into the first half of the section IV, and the sections IV-2 and IV-3 after the linear section to the latter part of the step IV.

On the other hand, from section IV-2, a new generation of fine cracks parallel to the stress and growth and bonding of existing micro cracks are active. (1) The change of θ angle, the area of triangle CC'G and triangle CEF, the variation of differential strain and differential stress, the arrangement of interval Ⅳ-2, the intersection point A 'and the intersection point G (Fig. 8) of the change in length (L ₁ to L ₅ ) and angles (α ₁ to α ₅ ) between the origin and the points on the volume strain curve are derived, Can be predicted. In other words, the progressive discrimination criterion for recognizing (predicting) 3 faces through the acquisition of section IV-2 on the volume strain curve is presented as follows.

7-3 Arrangement of section IV-2

Section IV-2 moves from right to left in the order of -1 → -2 → -3. Table 3 shows the relative increase in volume expansion due to the vertical density difference between the three specimens.

The degree of mutual overlap for the section IV-2 between the three specimens is higher than that of the geochemical granite (Fig. 6).

7-4 Movement path of intersection A 'and intersection G

(A ') between the vertical line extending in the X-axis direction at the initial point (C) of the section IV-2 and the horizontal line corresponding to the end point of the I-step, σ ₁ ^c .

From the initial point (A) of the section II on the volume strain curve, it is located on the left side of point A in -1 and on the right side of point A in -2 and -3 on the curve of the intersection (A ') of Geochang granite . The movement path of the intersection (A ') of Hapcheon granite is located on the left side of point A in -1, -2 and on the right side of point A in -3. It is located on the right side of A in common in -3 of two rocks (Fig. 6).

The length (mm) of A'-A is as follows, assuming that the volume strain of the X-axis 1000 (ε _v , × 10 ^-6 ) is 10 mm (1 cm) It is -1 (2.55), -2 (3.65), -3 (7.88) for Geocang granite, -1 (1.64), -2 (1.29) and -3 (1.05) for Hwacheon granite. The average length of the three specimens is in the order of geochang granite (4.66)> Hwacheon granite (1.32). The average length of geochang granites with relatively low uniaxial compressive strength and high density of microcracks is relatively large. In the case of Geochang granite, the differential strain (ε _v , × 10 ^-6 ) corresponding to the length of the intersection A 'and the intersection A is -150 (255) <-2 (365) <-3 Respectively.

The initial point (C) of section IV-2 and the end point (B) of step II were extended to derive the movement path of the intersection (G) which meets the X axis.

In Geocang granite, it moves to the right (-1) of the line E-E '→ the interior (-2, -3) of the section IV-1. On the other hand, Hwacheon granite has more approach (-2, -3) to the right (-1) to the line E-E 'of the line E-E' and does not move to the inside of the section IV-1. That is, when the reference line is the line E-E ', which is the right boundary line of the section IV-1, the intersection point (G) moves from the right side to the left side generally toward -1 → -2 → -3 specimen. Therefore, it can be deduced that the movement paths of the intersection G and the intersection A 'are opposite to each other (FIG. 6).

The length (mm) of E'-G is as follows, assuming that the volume strain of the X-axis 1000 (ε _v , × 10 ^-6 ) is 10 mm (1 cm). In Geochang granite, it is -1 (8.55), -2 (2.08) and -3 (5.18). In Hwacheon granite, it is -1 (7.73), -2 (2.76) and -3 (1.33). The average length of the three specimens is Geochang granite (5.27)> Hwacheon granite (3.94).

7-5 Changes in the angle of theta

Table 5 shows the angle θ of the straight line (C-B-G) connecting the initial point (C) of section IV-2 and the end point (B) The angle of theta was measured by magnifying the diagram of Fig. 6 on a program.

The θ angles of the three specimens of Geochang and Hapcheon granite are in the order of -1 (75.7 °, 77.3 °) <-2 (86.5 °, 81.2 °) <-3 (88.4 °, 84.6 °) (Fig. 7A).

The mean angles and anisotropy coefficients of the θ-angles of the three specimens were in order of Hwacheon granite (57.9, 9.0%) <Geochang granite (83.5, 15.2%), Geochang granite with low uniaxial compressive strength and high microcrack density And the anisotropy coefficient (%) are both large.

Rock
name Sample
No. θ (°) Geochang
granite
(G) G-1 75.7 G-2 86.5 G-3 88.4 Mean 83.5 An (%) 15.2 Hapcheon
granite
(H) H-1 77.3 H-2 81.2 H-3 84.6 Mean 57.9 An (%) 9.0

 Where An is the anisotropy coefficient (%) and can be calculated as Max-Min / average.

7-6 Area Change of Triangle CC'G

(C) extending the initial point (C) of the section IV-2 and connecting the point (C ') that meets the X axis, the initial point (C) of the section IV-2 and the end point B, a straight line CBG connecting points G to meet the X axis, and a straight line C'-G connecting C 'and G of the X axis divided by the two straight lines. (Cm ² ) and area ratio of the right triangle (ΔCC'G) captured by the above three straight lines are as shown in Table 6, assuming that the length of 1000 (ε _v , × 10 ^-6 ) .

Rock
name Sample
No. ΔCC'G ΔCEF Area (cm ² ) Area ratio Area (cm ² ) Area ratio Geochang
granite
(G) G-1 8.46 One 5.41 1.00 G-2 2.13 0.25 1.95 0.36 G-3 0.49 0.06 1.28 0.24 Mean 3.69 2.88 An (%) 215.7 143.2 Hapcheon
granite
(H) H-1 9.28 One 4.43 1.00 H-2 5.96 0.64 3.57 0.81 H-3 3.90 0.42 2.39 0.54 Mean 6.38 3.46 An (%) 84.3 59.0

 Where An is the anisotropy coefficient (%) and can be calculated as Max-Min / average.

The area of ΔCC'G of three specimens of geochemical and Hapcheon granite is -1 (8.46, 9.28)> -2 (2.13, 5.96)> 3 (0.49, 3.90) . The slope of the exponential function of Hapcheon granite (λ = 0.43), which has high uniaxial compressive strength and low microcrack density, is lower. -1 (1, 1)> -2 (0.25, 0.64)> -3 (0.06, 0.42) for the three specimens of the geochemical and Hapcheon granites based on the -1 specimen, (Fig. 7B).

The average area of the three specimens is Geochang granite (3.69) <Hwacheon granite (6.38) in order. The average area of Hwacheon granite with high uniaxial compressive strength and low microcrack density is large. On the other hand, the anisotropy coefficient (%) of the three specimens is in the order of Hwacheon granite (84.3%) <Geochang granite (215.7%) and Geochang granite with high uniaxial compressive strength and high microcrack density.

7-7 Area Change of Triangle CEF

In addition, a straight line (CF) extending from the initial point (C) of the section IV-2 to the point of intersection with the volume strain curve (F), the initial point (C) of the section IV- (CE) connecting the inflection point (E) of step IV, point (E), and point (C) of section IV-2 that extend in the vertical direction and meet the point of intersection with the volume strain curve A straight line EF is obtained. (Cm ² ) and the area ratio of the triangle (DELTA CEF) captured by the three straight lines are as shown in Table 6, assuming that the length of 1000 (ε _v , × 10 ^-6 )

The area of ΔCEF of three specimens of Geochang and Hapcheon granite is -1 (5.41, 4.43)> -2 (1.95, 3.57)> 3 (1.28, 2.39) . The slope of the exponential function of Hwacheon granite (λ = 0.30), which has high uniaxial compressive strength and low density of microcracks, is lower. Compared with the slope of the exponential function of ΔCC'G (0.43 to 1.42), the slope of the exponential function of ΔCEF (0.30 to 0.72) is low and the degree of area change between the three specimens is low (FIG.

(1, 1)> -2 (0.36, 0.81)> -3 (0.24, 0.54) for each of the three specimens of Geochang and Hapcheon granites based on the -1 specimen do.

The average area of the three specimens is Geochang granite (2.88) <Hwacheon granite (3.46) in order. The average area of Hacchae granite with high uniaxial compressive strength and low microcrack density is large. On the other hand, the anisotropy coefficient (%) of three specimens is Hapcheon granite (59.0%) and Geochang granite (143.2%). This characteristic is the same as the case of the area change of the triangle CC'G.

7-8th strain (longitudinal width of section IV-2)

The differential strain (Δε _v, ε _v ¹ -ε _v ² , × 10 ^-6 ) corresponding to the X-axis of section IV-2 was examined (Table 7).

Rock
name Sample
No.            Section IV-2 ε _v ¹ ε _v ² Δε _v
(ε _v -ε ¹ _v ²⁾ Geochang
granite
(G) G-1 4892 3458 1434 G-2 2860 2020 840 G-3 2895 -590 3485 Mean 3549 1629 1919 Hapcheon
granite
(H) H-1 3401 2315 1086 H-2 3243 2321 922 H-3 2258 1282 976 Mean 2967 1972 994

The strain rate of geochemical granite is -1 (1434) → -2 (840) (decrease), -2 (840) → -3 (3485) In Hapcheon granite, -1 (1086) -2 (922) (decrease), -2 (922) -3 (976) increase. A common regularity between the specimens of the two rocks was derived. The carapace strain of geochemical granite is the most typical pattern at -3 (3485) (Fig. 7d).

The mean value of the strain rate of the three specimens of each rock is Hapcheon granite (994) and Geochang granite (1919). Geochang granite, which has lower uniaxial compressive strength and higher grain density than Hacchin granite, has a large strain rate.

7-9th stress (width of section IV-2)

(Δσ, σ ₁ ² -σ ₁ ¹ , kg / cm ² ) and fracture ratios (σ ₁ ¹ / σ ₁ ^f , σ ₁ ² / σ ₁ ^f ) corresponding to the Y axis of section IV-2 Respectively. Table 8 shows the values of the differential stress and fracture ratios of section IV-2.

Rock
name Sample
No. Section IV-2 σ ¹ σ ₁ ^f σ ₁ ¹ / σ ₁ ^f σ ₁ ² σ ₁ ² / σ ₁ ^f Δσ
(? ₁ ² -σ ₁ ¹ ) Geochang
granite (G) G-1 1852 2048 0.90 1939 0.94 87 G-2 1701 1887 0.90 1802 0.95 101 G-3 1368 1587 0.86 1433 0.90 47 Mean 1640 1840 0.89 1724 0.93 78 Hapcheon
granite
(H) H-1 2126 2340 0.90 2230 0.95 104 H-2 2068 2211 0.93 2184 0.98 116 H-3 2124 2230 0.95 2219 0.99 95 Mean 2106 2260 0.93 2211 0.97 105

The differential stress of geochemical granite is -1 (87) - 2 (101) (increase), -2 (101) - 3 (47) In Hapcheon granite, it decreases from -1 (104) to -2 (116) (increase), -2 (116) to -3 (95) A common regularity between the specimens of the two rocks was derived. The differential stresses are the lowest in the three specimens having the highest vertical grain density arranged horizontally with respect to the direction of stress (Fig. 7E).

The relationship between the differential strain and the differential stress of the specimens of Geochang and Hapcheon granites is -1 → -2 (decrease and increase), -2 → -3 (increase and decrease). And inversely proportional regularities were derived. That is, the vertical width (differential strain) of the section IV-2 was low, while the common width with the width width (differential stress) of -2 was high (FIG. 7d, e).

The average value of the secondary stresses is in order of geochemical granite (78) <Hwacheon granite (105). The shear stress of Hapcheon granite with high uniaxial compressive strength and low microcrack density is large.

The fracture ratio of Geochang granite decreases from -2 (0.90 ~ 0.95) → -1 (0.90 ~ 0.94) → -3 (0.86 ~ 0.90). The fracture ratio of Hwacheon granite decreases from -3 (0.95 ~ 0.99) → -2 (0.93 ~ 0.98) → -1 (0.90 ~ 0.95). It lacks regularity between the specimens of both rocks.

The average values of fracture ratios are in the order of Geochang granite (0.89 ~ 0.93) <Hwacheon granite (0.93 ~ 0.97), and the shear stress of Hwacheon granite with high unconfined compressive strength and low microcrack density is large.

7-10 Change in length between each point on the origin and volume strain curve

The lengths of five straight lines OA, 0B, 0E, 0C and 0D, namely L ₁ , L ₂ , L ₃ , L ₄ and L ₅ , connecting the points of each step on the volume strain curve at the intersection (O) (Fig. 8). The length, average length and anisotropy coefficient (%) of the 5 straight lines are as shown in Table 9, assuming that the volume strain rate 1000 (ε _v , × 10 ^-6 ) of the X axis is 1 cm.

Rock
name Sample
No. L ₁ L ₂ L ₃ L ₄ L ₅ Geochang
granite
(G) G-1 7.2 10.0 11.9 13.6 13.4 G-2 3.9 6.0 9.5 11.6 11.9 G-3 3.3 5.7 8.8 9.4 9.3 Mean 4.80 7.23 10.07 11.53 11.53 An (%) 81.25 59.45 30.79 36.42 35.55 Hapcheon
granite
(H) H-1 5.6 9.9 13.1 14.6 14.7 H-2 5.8 8.4 11.7 14.1 14.4 H-3 4.5 7.4 10.6 13.9 14.1 Mean 5.30 8.57 11.80 14.20 14.40 An (%) 20.75 29.18 21.19 4.93 4.17

 Here, the unit is cm, and An is the anisotropy coefficient (%), which can be calculated as Max-Min / average.

Looking at the area of the length of five straight lines of three specimens of Geochang and Hapcheon granite, we derive a common regularity that is arranged in order of -3 (lower region) <-2 (middle region) <-1 (upper region) (Fig. 9A, b).

The anisotropy coefficient (%) of the three specimens is in order of Hwacheon granite (lower area) <Geochang granite (upper area), and Geochang granite with high uniaxial compressive strength and high microcrack density has high anisotropy coefficient (Fig.

7-11 Change of intersection angle of each point on origin and volume strain curve

0B, 0E, 0C, and 0D, connecting the points of each step on the volume strain curve at the intersection (O) of the X and Y axes.

The intersection angle α ₁ between the straight line OA and the horizontal line, the intersection angle α ₂ between the straight line OB and the straight line OA, the intersection angle α ₃ between the straight line OE and the straight line OB, the intersection angle α ₄ between the straight line OC and the straight line OE ), The crossing angle (α ₅ ) between the straight line OD and the line OC, and the average angle and anisotropy coefficient (%) of the crossing angle are shown in Table 10.

Rock
name Sample
No. α ₁ α ₂ α ₃ α ₄ α ₅ Geochang
granite
(G) G-1 19.5 12.2 8.4 11 6.5 G-2 31 12.2 17.3 10.3 6.3 G-3 36.8 10 11 9.1 27.9 Mean 29.1 11.5 12.2 10.1 13.6 An (%) 59.5 19.2 72.8 18.8 159.2 Hapcheon
granite
(H) H-1 34.8 15.1 8.4 11.6 7.1 H-2 33.6 12.2 11.2 13.1 6.6 H-3 44.7 12.2 8.4 11 6.5 Mean 37.7 13.2 9.3 11.9 6.7 An (%) 29.4 22.0 30.0 17.6 8.9

Where An is the anisotropy coefficient (%) and can be calculated as Max-Min / average.

The α angle of the two rocks is commonly derived from α _{1 →} α _{2 →} α ₃ (decrease), α _{3 →} α ₄ (increase) _{, and} α _{4 →} α ₅ (decrease). Of the three specimens of the two rocks, -2 and -3 lack regularity (Fig. 9d).

The anisotropy coefficient (%) for the five angles is in the order of Hapcheon granite (lower area) and Geochang granite (upper area). The anisotropy coefficient of geochang granite with high uniaxial compressive strength and high microcrack density is high. The anisotropy coefficient (%) of two rocks has a common regularity of α _{1 →} α ₂ (decrease), α _{2 →} α ₃ (increase), α _{3 →} α ₄ (decrease) _{, and} α _{4 →} α ₅ (Fig. 9E).

In the present invention, a progressive discriminant criterion for predicting three or three sides of granite is derived based on the section IV-2 obtained on the volume strain curve.

1. Arrangement of section IV-2

Section IV-2 moves from right to left in the order of -1 → -2 → -3. Which means an increase in the relative volume expansion due to the density difference of the vertical grains between the three specimens.

The degree of mutual overlap for section IV-2 between the three specimens shows a high degree of superposition of Hacchae granite, which has high uniaxial compressive strength and low microcrack density.

2. Movement path of intersection A 'and intersection G

From the initial point (A) of the section II on the volume strain curve, the left side of point A, -2 and -3 are located on the right side of point A . The movement path of the intersection (A ') of Hacchae granite is located on the left side of point A in -1 and -2 on the right side of point A. It is located on the right side of A in common with -3 of two rocks.

And the movement route of the intersection (G) is derived. When the reference line is the line E-E ', which is the right boundary line of the section IV-1, the intersection point (G) moves from the right side to the left side generally toward the -1 → -2 → -3 specimen. The movement paths of the intersection G and the intersection A 'are opposite to each other. The average length of A'-A, E'-G is in the order of geochang granite> Hwacheon granite.

3. Change in the angle of theta:

The θ-angles of the three specimens of Geochang and Hapcheon granite are in the order of -1 <-2 <-3 and increase in common. The mean angle and anisotropy coefficient (%) of θ angle are in the order of Hwacheon granite <Geochang granite. The average angle and anisotropy coefficient (%) of geochang granite with low uniaxial compressive strength and high microcrack density are high.

4. Change of area of triangle CC'G

The area of ΔCC'G for each of the three specimens of Geochang and Hacchae granite is in the order of -1> -2> 3 and decreases in the form of negative exponential function. The slope of the exponential function of Hacchae granite is low.

The average area of the three specimens is Geochang granite (3.69) and Hapcheon granite (6.38), and the average area of Hapcheon granite is large. On the other hand, the anisotropy coefficient (%) of the three specimens is in the order of Hwacheon granite (84.3%) <Geochang granite (215.7%), and Geochang granite has high anisotropy coefficient.

5. Area change of triangle CEF

The area of ΔCEF for three specimens of Geochang and Hapcheon granite is in the order of -1> -2> 3, and decreases in the form of negative exponential function. The slope of the exponential function of Hacchae granite is low.

The average area of the three specimens is Geochang granite (2.88) and Hapcheon granite (3.46), and the average area of Hapcheon granite is large. On the other hand, the anisotropy coefficient (%) of three specimens is in order of Hwacheon granite (59.0%) and Geochang granite (143.2%), and Geochang granite has high anisotropy coefficient. This characteristic is the same as the case of the area change of? CC'G.

6. Primary strain (longitudinal extent of section IV-2)

The strain rate of geochemical granite is -1 (1434) → -2 (840) (decrease), -2 (840) → -3 (3485) In Hapcheon granite, -1 (1086) -2 (922) (decrease), -2 (922) -3 (976) increase. A common regularity between the specimens of the two rocks was derived.

The mean value of the strain rate of the three specimens of each rock is Hapcheon granite (994) and Geochang granite (1919). Geochang granite has large car strain rate.

7. Secondary stress (width of section IV-2)

The differential stress of geochemical granite is -1 (87) - 2 (101) (increase), -2 (101) - 3 (47) In Hapcheon granite, it decreases from -1 (104) to -2 (116) (increase), -2 (116) to -3 (95) A common regularity between the specimens of the two rocks was derived. In the three specimens having the highest density of vertical grains arranged horizontally and in the direction of stress, the differential stress is the lowest in common.

The relationship between differential strain and differential stress of Geochang and Hapcheon granite is -1 → -2 (decrease and increase), -2 → -3 (increase and decrease). And inversely proportional regularities were derived. In other words, the vertical width (differential strain) of section IV-2 is low, while the horizontal width (differential stress) is high.

The average value of the secondary stresses is in the order of Geocang granite (78) <Hwacheon granite (105), and the shear stress of Hacchae granite is larger.

8. Change in the length between the origin and each point on the volume strain curve

When we look at the length of five straight lines of three specimens of Geochang and Hapcheon granite, we found a common regularity in order of -3 (subregion) <-2 (middle region)> 1 (upper region) .

The anisotropy coefficient (%) of three specimens is in order of Hwacheon granite (lower area) <Geochang granite (upper area), and Geochang granite has high anisotropy coefficient.

9. Angular variation of each point on the origin and volume strain curve

From the angular changes of Geochang and Hapcheon granites _, we obtained a common regularity that α ₁ → α ₂ → α ₃ (decrease), α ₃ → α ₄ (increase) _, α ₄ → α ₅ (decrease) . Of the three specimens of the two rocks, -2 and -3 lack regularity.

The anisotropy coefficient (%) for the five angles is in the order of Hapcheon granite (lower area) and Geochang granite (upper area). The anisotropy coefficient of geochang granite is high.

The anisotropy coefficient (%) of two rocks has a common regularity of α ₁ → α ₂ (decrease), α ₂ → α ₃ (increase), α ₃ → α ₄ (decrease) _{, and} α ₄ → α ₅ Respectively.

The results of the evaluation of microcracks through the photographs of the geochang and Hacheon granite slabs were compared with the various discriminant factors obtained on the concurrent and volumetric strain curves. From these contrasts, we have derived major discriminant factors which commonly represent the three quarries of Geochang and Hapcheon granite.

As described above, an optimal embodiment has been disclosed in the drawings and specification. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (8)

delete A rock block sampling step for obtaining a square block of rock from the granite;
A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces;
A rock block dividing step of dividing the rock block into a plurality of square rock samples;
A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen;
A stress applying step of applying stress to the core specimens; And
The stress-strain curves of the core specimens are measured, and the volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four strength sections (Ⅰ, Ⅱ, Ⅲ and Ⅳ), and the linear section with the shape of a straight line is divided into Ⅳ-2 sections in the stress-volume strain curve of step Ⅳ among the strength sections of the 4th step, - a quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the volume strain curves; / RTI &gt;
In the texture quantitative evaluation step,
The relative strength of the grains is evaluated to be lower as the position of the section of the line IV-2, which is a linear section having the shape of a straight line in the stress-strain curve, is located on the right side. Evaluation method of determination.
A rock block sampling step for obtaining a square block of rock from the granite;
A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces;
A rock block dividing step of dividing the rock block into a plurality of square rock samples;
A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen;
A stress applying step of applying stress to the core specimens; And
The stress-strain curves of the core specimens are measured, and the volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four strength sections (Ⅰ, Ⅱ, Ⅲ and Ⅳ), and the linear section with the shape of a straight line is divided into Ⅳ-2 sections in the stress-volume strain curve of step Ⅳ among the strength sections of the 4th step, - a quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the volume strain curves; / RTI &gt;
In the texture quantitative evaluation step,
The stress-movement of the intersection point (A ') of the vertical lines and horizontal lines corresponding to the end points of σ ₁ ^c of Ⅰ step extending volume strain curve in the X-axis direction from the initial point (C) of the section Ⅳ-2 path And the relative strength of the grains is evaluated to be low with respect to the grains located on the left side of the initial point (A) based on the initial point (A) of the section II of the intersection (A '). Method of evaluation of resolution using distribution characteristics of.
A rock block sampling step for obtaining a square block of rock from the granite;
A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces;
A rock block dividing step of dividing the rock block into a plurality of square rock samples;
A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen;
A stress applying step of applying stress to the core specimens; And
The stress-strain curves of the core specimens are measured, and the volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four strength sections (Ⅰ, Ⅱ, Ⅲ and Ⅳ), and the linear section with the shape of a straight line is divided into Ⅳ-2 sections in the stress-volume strain curve of step Ⅳ among the strength sections of the 4th step, - a quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the volume strain curves; / RTI &gt;
In the texture quantitative evaluation step,
The initial angle (C) of the section IV-2 and the end point (B) of the section II were extended in the stress-volume strain curve to analyze the angle of the straight line CBG connecting the point G , and the relative strength of the texture is evaluated to be lower as the angle of theta is smaller. The method of evaluating the texture using the distribution characteristic of the volume strain curve of the granite.
A rock block sampling step for obtaining a square block of rock from the granite;
A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces;
A rock block dividing step of dividing the rock block into a plurality of square rock samples;
A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen;
A stress applying step of applying stress to the core specimens; And
The stress-strain curves of the core specimens are measured, and the volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four strength sections (Ⅰ, Ⅱ, Ⅲ and Ⅳ), and the linear section with the shape of a straight line is divided into Ⅳ-2 sections in the stress-volume strain curve of step Ⅳ among the strength sections of the 4th step, - a quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the volume strain curves; / RTI &gt;
In the texture quantitative evaluation step,
A straight line C-C 'connecting the initial point C of the section IV-2 and connecting the point C' that meets the X axis is obtained from the stress-strain curve of the section IV-2, C) and an end point (B) of the step II to extend a straight line CBG connecting points G to meet with the X axis, (C'-G) obtained by connecting the three straight lines (C-C ', CBG and C'-G) are analyzed and the area ratio of the right triangle (? CC'G) captured by the three straight lines And the relative strength of the grains is evaluated to be lower as the area ratio is larger.
A rock block sampling step for obtaining a square block of rock from the granite;
A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces;
A rock block dividing step of dividing the rock block into a plurality of square rock samples;
A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen;
A stress applying step of applying stress to the core specimens; And
The stress-strain curves of the core specimens are measured, and the volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four strength sections (Ⅰ, Ⅱ, Ⅲ and Ⅳ), and the linear section with the shape of a straight line is divided into Ⅳ-2 sections in the stress-volume strain curve of step Ⅳ among the strength sections of the 4th step, - a quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the volume strain curves; / RTI &gt;
In the texture quantitative evaluation step,
(CF) extending from the initial point (C) of the section IV-2 to the point of intersection of the volume strain curve and the point of intersection (F) at the initial point (C) of the section IV-2 in the stress- C) and the inflection point (E) of the stage III and IV are obtained. The point (E) and the point of intersection with the volume strain curve extending in the vertical direction at the initial point (C) And the area of the triangle (? CEF) captured by the three straight lines (CF, CE, EF) is analyzed after calculating a straight line EF interconnected with the reference line F. The wider the area, Wherein said method comprises the steps of:
The method according to claim 6,
The area ratio of the triangle (? CEF) captured by the three straight lines (CF, CE, EF) is analyzed and the relative strength of the grains is evaluated as being lower as the area ratio is larger. Assessment Methods.
A rock block sampling step for obtaining a square block of rock from the granite;
A rock block surface cutting step for cutting the surface of the rock block in a direction parallel to the three pitting surfaces;
A rock block dividing step of dividing the rock block into a plurality of square rock samples;
A core specimen manufacturing step of fabricating respective core specimens in a direction perpendicular to the three crystal faces of the rock specimen;
A stress applying step of applying stress to the core specimens; And
The stress-strain curves of the core specimens are measured, and the volume strain rate (ε _v ) is calculated to determine a stress-volume strain curve. The rock fracture process is divided into four strength sections (Ⅰ, Ⅱ, Ⅲ and Ⅳ), and the linear section with the shape of a straight line is divided into Ⅳ-2 sections in the stress-volume strain curve of step Ⅳ among the strength sections of the 4th step, - a quantitative evaluation step of evaluating the relative strength of the three texture surfaces by analyzing the distribution characteristics of the volume strain curves; / RTI &gt;
In the texture quantitative evaluation step,
In the stress-strain curve, five straight lines OA, 0B, and 0E connecting points (I, II, III, IV-1 and IV-2) on the volume strain curve at the intersection O between the X and Y axes (L ₁ , L ₂ , L ₃ , L ₄ , and L ₅ ) of 0C and 0D are measured and analyzed to evaluate the relative strength of the grains to a lower value as the length of the five straight lines becomes longer Evaluation method of resolution using distribution characteristics of strain curves.

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