Browse > Article
http://dx.doi.org/10.22807/KJMP.2021.34.3.193

Influence of Microcracks in Geochang Granite on Brazilian Tensile Strength  

Park, Deok-Won (Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources)
Publication Information
Korean Journal of Mineralogy and Petrology / v.34, no.3, 2021 , pp. 193-208 More about this Journal
Abstract
The characteristics of the microcrack lengths(①), microcrack spacings(②) and Brazilian tensile strengths(③) related to the six directions of rock cleavages(H2~R1) in Geochang granite were analyzed. First, the 18 cumulative graphs for the above three major factors representing unique characteristics of the rock cleavages were made. Through the general chart for these graphs classified into three planes and three rock cleavages, the 28 parameters on the length, spacing and Brazilian tensile strength have been determined. The results of correlation analysis among these parameters are summarized as follows. Second, the above parameters were classified into six groups(I~VI) according to the sorting order on the magnitude of parameter values among three rock cleavages and three planes. The values of parameters belonging to group I and II are in order of R(rift) < G(grain) < H(hardway) and H < G < R. The values of the 8 parameters on the length of line(os2, 𝚫s, 𝚫L and oSmean), the exponent(λLmean and λSmean), the slope(amean) and the anisotropy coefficient (Anmean) are in order of R < G < H and H'(hardway plane) < G'(grain plane) < R'(rift plane). Third, the noticeable differences in distribution patterns among the six types of charts for three planes and three rock cleavages are as follows. From the chart for three planes, the values of 𝚫L, 𝚫s and 𝚫σt, corresponding to the distance between two points where the two fitting lines meet on the X-axis, increase in the order of R' < H' < G'. In particular, the two graphs of R2 and G2 related to the length and Brazilian tensile strength are almost parallel to each other and show the distribution characteristics of hardway plane. Among the graphs related to the Brazilian tensile strength, the overall shape for hardway plane is similar to that for grain. From the chart for three rock cleavages, the slopes of the graphs related to the length increase in the order of R < G < H, while those of the graphs related to the spacing and Brazilian tensile strength decrease in the order of R < G < H. Lastly, the characteristics of variation among the six rock cleavages, the three planes and the three rock cleavages were visualized through the correlation chart among the above parameters from this study.
Keywords
Microcrack lengths; Microcrack spacings; Brazilian tensile strengths; Rock cleavages; Granite; Parameters; Correlation chart;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 Kudo, Y., Hashimoto, K., Sano, O. and Nakagawa, K., 1986, The empirical knowledge of quarryman and physical properties of granite. Japanese Society of Soil Mechanics and Foundation Engineering, 34, 47-51.
2 Park, D.W., 2016a, Evaluation for rock cleavage using distribution of microcrack spacings (I). The Journal of the Petrological Society of Korea, 25(1), 13-27.   DOI
3 Seo, Y.S. and Park, D.W., 2003, Mechanical anisotropy of Jurassic granite in Korea. The Journal of Engineering Geology, 13, 257-266.   DOI
4 Zhuang, L., Diaz, M. B., Jung, S. G. and Kim, K. Y., 2016, Cleavage dependent indirect tensile strength of Pocheon granite based on experiments and DEM simulation. Tunnel and Underground Space, 26.4, 316-326.
5 Park, D.W., 2020a, Evaluation for rock cleavage using distributional characteristics of microcracks and Brazilian tensile strengths. Korean Journal of Mineralogy and Petrology, 33, 99-114.   DOI
6 Park, D.W., 2020b, Mechanical characteristics of the rift, grain and hardway planes in Jurassic granites. Korean Journal of Mineralogy and Petrology, 33, 273-291.   DOI
7 Park, D.W., Kim, H.C., Lee, C.B., Hong, S.S., Chang, S.W. and Lee, C.W., 2004, Characteristics of the rock cleavage in Jurassic granite, Pocheon. The Journal of the Petrological Society of Korea, 13, 133-141.
8 Park, D.W. and Kim, K.S., 2021, Influence of microcrack on Brazilian tensile strength of Jurassic granite in Hapcheon. Korean Journal of Mineralogy and Petrology, 34, 41-56.   DOI
9 Park, D.W., Kim, K.S. and Lee, Y.M., 2017, Evaluation for rock cleavage using distribution of Brazilian tensile strength, Korean Intellectual Property Office, 10-1734788, 1-25.
10 Park, D.W., Seo, Y.S., Jeong, G.C. and Kim, Y.K., 2001, Microscopic analysis of the rock cleavage for Jurassic granite in Korea. The Journal of Engineering Geology, 11, 51-62.
11 Peng, S.S. and Johnson, A.M., 1972, Crack growth and faulting in cylindrical specimens of Chelmsford granite. International Journal of Rock Mechanics and Mining, 9, 37-86.   DOI
12 Chen, Y., Nishiyama, T., Kita, H. and Sato, T., 1997, Correlation between microfracture type and splitting planes of Inada granite and Kurihashi granodiorite. Journal of the Japan Society of Engineering Geology, 38.4, 196-204.   DOI
13 Dai, F. and Xia, K., 2010, Loading rate dependence of tensile strength anisotropy of Barre granite. Pure and Applied Geophysics. 167, 1419-1432.   DOI
14 Fujii, Y., Takemura, T., Takahashi, M., Weiren, L.I.N. and Akaiwa, S., 2005, The feature of uniaxial tensile fractures in granite and their relation to rock anisotropy. Journal of the Japan Society of Engineering Geology, 46, 227-231.   DOI
15 Jang, B.A. and Oh, S.H., 2001, Mechanical anisotropy dependent on the rock fabric in the Pocheon granite and its relationship with microcracks. The Journal of Engineering Geology, 11, 191-203.
16 Kim, M.K., 2015, The mechanical properties of the Geochang granite. Tunnel and Underground Space, 25, 24-36.   DOI
17 Kudo, Y., Hashimoto, K., Sano, O. and Nakagawa, K., 1987, Relation between physical anisotropy and microstructures of granitic rock in Japan. In 6th ISRM Congress. International Society for Rock Mechanics.
18 Lin, W. and Takahashi, M., 2008, Anisotropy of strength and deformation of Inada granite under uniaxial tension. Chinese Journal of Rock Mechanics and Engineering, 27, 2463-2472.   DOI
19 Park, D.W., 2007, Orientations of vertical rift and grain planes in Mesozoic granites, Korea. The Journal of the Petrological Society of Korea, 16, 12-26.
20 Lee, S.E., Cho, S.H., Seo, Y.S., Yang, H.S. and Park, H.M., 2001, The effect of microcracks on the mechanical anisotropy of granite. Material science Research International, 7, 7-13.
21 Park, D.W., 2011, Characteristics of the rock cleavage in Jurassic granite, Hapcheon. The Journal of the Petrological Society of Korea, 20, 219-230.   DOI
22 Park, D.W., 2015a, Characteristics of the rock cleavage in Jurassic granite, Geochang. The Journal of the Petrological Society of Korea, 24(3), 153-164.   DOI
23 Park, D.W., 2015b, Evaluation for rock cleavage using distribution of microcrack lengths. The Journal of the Petrological Society of Korea, 24(3), 165-180.   DOI
24 Park, D.W., 2016b, Evaluation for rock cleavage using distribution of microcrack spacings (II). The Journal of the Petrological Society of Korea, 25(2), 151-163.   DOI
25 Park, D.W., 2016c, Evaluation for rock cleavage using distribution of microcrack spacings (III). The Journal of the Petrological Society of Korea, 25(4), 1-14.   DOI