Microscopic failure of yellow sandstone with different-sized grains and mineral composition

Abstract

The effect of grain size on the microscopic failure of yellow sandstone was investigated via a series of laboratory experiments. The compressive strength, elastic modulus, tensile strength, internal cohesion, and friction angle of the sandstone are inversely proportional to the grain size. A combination of observation techniques (geological thin sections and scanning electron microscopy) indicated that the quartz and feldspar particles act as the skeleton in yellow sandstone, and the other minerals form the cement that bonds the skeleton particles together. The skeleton particles in fine-grained sandstone are rounder and more compact than those in medium-grained sandstone. Fine-grained sandstone has the highest content of skeleton particles and the densest. In contrast, coarse-grained sandstone exhibits particles that are more angular and loosely packed. As the grain size increases, the percentage of cementing material rises substantially. However, the percentages of SiO₂ and quartz rapidly decrease. The failure process in the yellow sandstone initiates in the cementing materials that have lower strength. Shortly thereafter, the failure extends further to the skeleton grains. X-ray powder diffraction experiments suggest that the strength of yellow sandstone relates to the quartz content of the skeleton grains: the greater the amount of quartz, the greater the strength.

Keywords

sandstone / grain size / mechanical test / failure mode / microscopic structure / mineralogical composition

References

[1] OliveiraD, DiederichsM S. Tunnel support for stress induced failures in Hawkesbury Sandstone [J]. Tunnelling and Underground Space Technology, 2017, 64: 10-23

[2] MishraS, ChakrabortyT, BasuD, et al. . Characterization of sandstone for application in blast analysis of tunnel [J]. Geotechnical Testing Journal, 2020, 43(2): 20180270

[3] MartinC DThe strength of massive Lac du Bonnet granite around underground openings [D], 1993, Winnipeg, Manitoba, Canada, University of Manitoba

[4] YangS-q, NiH-m, WenSen. Spatial acoustic emission evolution of red sandstone during multi-stage triaxial deformation [J]. Journal of Central South University, 2014, 2183316-3326

[5] HatzorY H, PalchikV. The influence of grain size and porosity on crack initiation stress and critical flaw length in Dolomites [J]. International Journal of Rock Mechanics and Mining Sciences, 1997, 34(5): 805-816

[6] GongF-q, WuW-x, ZhangLe. Brazilian disc test study on tensile strength-weakening effect of high pre-loaded red sandstone under dynamic disturbance [J]. Journal of Central South University, 2020, 27(10): 2899-2913

[7] GongF-q, WangY-l, LuoSong. Rockburst proneness criteria for rock materials: Review and new insights [J]. Journal of Central South University, 2020, 27(10): 2793-2821

[8] HsiehY M, LiH H, HuangT H, et al. . Interpretations on how the macroscopic mechanical behavior of sandstone affected by microscopic properties—Revealed by bonded-particle model [J]. Engineering Geology, 2008, 99(1–2): 1-10

[9] EberhardtE BBrittle rock fracture and progressive damage in uniaxial compression [D], 1998, Saskatoon, Saskatchewan, Canada, The University of Saskatchewan

[10] LiZ, RaoQ-hua. Quantitative determination of PFC^3D microscopic parameters [J]. Journal of Central South University, 2021, 28(3): 911-925

[11] CundallP. A computer model for simulating progressive, large-scale movements in blocky rock systems [C]. Proceedings of the International Symposium on Rock Mechanics, 1971, France, Nancy: 129136

[12] EftekhariM, BaghbananA, HashemolhosseiniH, et al. . Mechanism of fracture in macro- and micro-scales in hollow centre cracked disc specimen [J]. Journal of Central South University, 2015, 22(11): 4426-4433

[13] SharafisafaM, AliabadianZ, ShenL-ming. Crack initiation and failure of block-in-matrix rocks under Brazilian test using digital image correlation [J]. Theoretical and Applied Fracture Mechanics, 2020, 109: 102743

[14] VutukuriV S, LamaR D, SalujaS SHandbook on mechanical properties of rocks [M], 1974, Stafa-Zurich, Trans Tech Publications

[15] AlneasanM, BehniaM. An experimental investigation on tensile fracturing of brittle rocks by considering the effect of grain size and mineralogical composition [J]. International Journal of Rock Mechanics and Mining Sciences, 2021, 137104570

[16] EberhardtE, SteadD, StimpsonB, et al. . Identifying crack initiation and propagation thresholds in brittle rock [J]. Canadian Geotechnical Journal, 1998, 35(2): 222-233

[17] PeckL, BartonC C, GordonR B. Microstructure and the resistance of rock to tensile fracture [J]. Journal of Geophysical Research, 1985, 90(B13): 11111-11570

[18] LazarO R, BohacsK M, MacquakerJ H S, et al. . Capturing key attributes of fine-grained sedimentary rocks in outcrops, cores, and thin sections: Nomenclature and description guidelines [J]. Journal of Sedimentary Research, 2015, 85(3): 230-246

[19] DudleyJ W, BrignoliM, CrawfordB R, et al. . ISRM suggested method for uniaxial-strain compressibility testing for reservoir geomechanics [J]. Rock Mechanics and Rock Engineering, 2016, 49(10): 4153-4178

[20] Suggested methods for determining tensile strength of rock materials [J]. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1978, 15(3): 99–103. DOI: https://doi.org/10.1016/0148-9062(78)90003-7.

[21] ChoN, MartinC D, SegoD C. Development of a shear zone in brittle rock subjected to direct shear [J]. International Journal of Rock Mechanics and Mining Sciences, 2008, 45(8): 1335-1346

[22] BradyB H G, BrownE TRock mechanics: for underground mining (3rd edition) [M], 2004, Dordrecht, Kluwer Academic Publishers

[23] GoodmanR EIntroduction to rock mechanics 2nd edition [M], 1989, New York, Wiley

[24] AtapourH, MortazaviA. The influence of mean grain size on unconfined compressive strength of weakly consolidated reservoir sandstones [J]. Journal of Petroleum Science and Engineering, 2018, 17163-70