Authors: Mutaz, E; Serati, M; Williams, DJ; Nguyen, VT

Open access courtesy of:


Cite As:
Mutaz, E, Serati, M, Williams, DJ & Nguyen, VT 2020, 'On the accurate strain measurements for the crack initiation determination', in J Wesseloo (ed.), Proceedings of the Second International Conference on Underground Mining Technology, Australian Centre for Geomechanics, Perth, pp. 401-412,

Download citation as:   ris   bibtex   endnote   text   Zotero

Due to the huge demand for natural resources and minerals at a global scale, mining depths have progressively increased over the past decades to 1,000 m and deeper. However, despite many successes, deep mining operations are now facing new challenges never experienced before, including rock spalling and unwanted slabbing failures. This phenomenon is characterised as a sudden explosion-like fracture, which can affect the long-term viability and stability of deep underground mining. According to the literature, the most indicative predictor of the spalling strength at laboratory scale is the determination of the crack initiation point, which is defined as the onset of stress-induced damage in low-porosity rocks after the closure of preexisting cracks. Hence, many methods have been developed to identify this critical design parameter, based mainly on the measurement of vertical, lateral or volumetric strains. That is, an accurate measurement of strain is deemed critical in determining the onset of the crack initiation threshold in the study of rock failure. Nevertheless, it remains difficult to determine the actual sample deformation in many geotechnical test apparatuses (i.e. multi-stage triaxial, Hoek cell, true triaxial, etc.), in which the measured deformation by linear variable differential transformers (LVDTs) is the cumulative deformation of the load frame itself, the loading platens, and the sample. As a result, relying on these deformation measurements can lead to erroneous estimation of the material’s strain behaviour. This work presents a qualitative study on how to measure the actual sample deformation in a multi-functional true triaxial testing apparatus recently commissioned at the Geotechnical Engineering Centre (GEC) within the School of Civil Engineering at The University of Queensland (Brisbane, Australia).

Keywords: crack initiation threshold, spalling strength, strain measurement, true triaxial testing, strain gauges

Aseyeva, T, Alexeev, A, Viktorov, V & Stratikov, G 1987, ‘A plant for three-axis compression tests of prismatic specimens’, U.S.S.R. Patent No. 1285340, Priority 1984 (in Russian).
Bahaaddini, M, Serati, M, Masoumi, H & Rahimi, E 2019, ‘Numerical assessment of rupture mechanisms in Brazilian test of brittle materials’, International Journal of Solids and Structures, vol. 180–181, pp. 1–12.
Blake, W & Hedley, DG 2003, Rockbursts, Case Studies from North American Hard-Rock Mines, Society for Mining, Metallurgy and Exploration Inc., Englewood.
Brace, WF, Paulding, B & Scholz, C 1966, ‘Dilatancy in the fracture of crystalline rocks’, Journal of Geophysical Research, vol. 71, pp. 3939–3953.
Brown, L & Hudyma, M 2017, Canadian Seismicity and Rockburst Database, technical report, January 2017.
Chang, C & Haimson, B 2000, ‘True triaxial strength and deformability of the German Continental Deep Drilling Program (KTB) deep hole amphibolite’, Journal of Geophysical Research, vol. 105, pp. 18999–19013.
Diederichs, MS 2007, ‘The 2003 Canadian Geotechnical Colloquium: mechanistic interpretation and practical application of damage and spalling prediction criteria for deep tunnelling’, Canadian Geotechnical Journal, vol. 44, pp. 1082–1116.
Duan, G, Li, J, Zhang, J, Assefa, E & Sun, X 2019, ‘Mechanical properties and failure modes of rock specimens with specific joint geometries in triaxial unloading compressive test’, Advances in Materials Science and Engineering, vol. 2019,
Feng, X-T, Zhang, X, Kong, R & Wang, G 2016, ‘A novel Mogi type true triaxial testing apparatus and its use to obtain complete
stress–strain curves of hard rocks’, Rock Mechanics and Rock Engineering, vol. 49, pp. 1649–1662.
Fujii, Y, Ishijima, Y & Deguchi, G 1997, ‘Prediction of coal face rockbursts and microseismicity in deep longwall coal mining’, International Journal of Rock Mechanics and Mining Sciences, vol. 34, no. 01, pp. 85–96.
Gong, F, Luo, Y, Li, X-B, Si, X-F & Tao, M 2018, ‘Experimental simulation investigation on rockburst induced by spalling failure in deep circular tunnels’, Tunnelling and Underground Space Technology, vol. 81, pp 413–427.
Guo, R, Pan, CL & Yu, RC 2003, Theory and Technique of Mining Dealing with Hard Rock Deposits Liable to Rockburst, Metallurgical Industry Press, Beijing.
Hargraves, AJ 1980, ‘Keynote address – a review of instantaneous outburst data’, Symposium on the Occurrence Prediction and Control of Outbursts in Coal Mines Symposium, The Australian Institute of Mining and Metallurgy, Melbourne, pp. 1–18.
He, M, Miao, J & Li, D 2007, ‘Experimental study on rockburst processes of granite specimen at great depth’, Chinese Journal of Rock Mechanics and Engineering, vol. 26, no. 5, pp. 865–876 (in Chinese).
Ingraham, M, Issen, K & Holcomb, D 2013, ‘Response of Castlegate sandstone to true triaxial states of stress’, Journal of Geophysical Research, vol. 118, pp. 536–552.
Kun, D, Ming, T, Li, X-B & Jian, Z 2016, ‘Experimental study of slabbing and rockburst induced by true-triaxial unloading and local dynamic disturbance’, Rock Mechanics and Rock Engineering, vol. 49, pp. 3437–3453.
Kusui, A & Villaescusa, E 2016, ‘Seismic response prior to spalling failure in highly stressed underground tunnels’, Proceedings of the Seventh International Conference & Exhibition on Mass Mining (MassMin 2016), Australasian Institute of Mining and Metallurgy, Melbourne.
Kwasniewski, M, Takahashi, M & Li, X 2003, ‘Volume changes in sandstone under true triaxial compression conditions’, Proceedings of the 10th ISRM Congress International Society for Rock Mechanics, South African Institute of Mining and Metallurgy, Johannesburg, pp. 683–688.
Lajtai, EZ 1974, ‘Brittle fracture in compression’, International Journal of Fracture Mechanics, vol. 10, pp. 525–536.
Li, X, Shi, L, Bai, B, Li, Q & Xu, D 2012, ‘True-triaxial testing techniques of rocks – state of the art and future perspectives’, in M Kwaśniewski, X Li & M Takahashi (eds), True Triaxial Testing of Rocks, CRC Press, Boca Raton, pp. 3–18.
Martin, CD & Chandler, NA 1994, ‘The progressive fracture of Lac du Bonnet granite’, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, vol. 31, no. 6, pp.643–659.
Martna, J 1972, ‘Selective overbreake in the Suorva-Vietas tunnel caused by rock pressure’, Proceeding of the International Symposium on Underground Openings, Swiss Society for Soil Mechanics and Foundation Engineering, Zürich, pp. 141–145.
Mogi, K 1970, ‘Effect of the triaxial stress system on rock failure’, Rock Mechanics In Japan, vol. 1, pp. 53–55.
Mutaz, E, Serati, M, Nguyen, VT & Williams, DJ 2019, ‘Effects of testing conditions on measurement of material’s elastic properties’, Proceedings of the ISRM2019 Specialized Conference, International Society for Rock Mechanics and Rock Engineering, Lisbon.
Nicksiar, M & Martin, CD 2012, ‘Evaluation of methods for determining crack initiation in compression tests on low-porosity rocks’, Rock Mechanics and Rock Engineering, vol. 45, pp. 607–617.
Potvin, Y, Hudyma, M & Jewell, R 2000, ‘Rockburst and seismic activity in underground Australian mines - an introduction to a new research project’, ISRM International Symposium, International Society for Rock Mechanics and Rock Engineering, Lisbon.
PwC Australia, Mine 2019: Resourcing the Future,
Selmer-Olsen, R 1988, ‘General engineering design procedures’, Norwegian Tunneling Today, pp. 53–58.
Serati, M , Mutaz , E, Williams, DJ, Quintero OS, Karlovsek, J & Hanzic, L 2020, ‘Failure mode of concrete under polyaxial stresses’, Proceedings of the 54th US Rock Mechanics/Geomechanics Symposium, American Rock Mechanics Association, Alexandria.
Shi, L, Li, X, Bai, B, Li, Q & Feng, X 2012, ‘Numerical analysis of loading boundary effects in Mogi-type true triaxial tests’, in M Kwasniewski, X Li & M Takahashi (eds), True Triaxial Testing of Rocks, CRC Press, Boca Raton, pp. 19–33.
Silva, AL, Varanis, M, Mereles, AG, Oliveira, C & Balthazar, JM 2019, ‘Study of strain and deformation measurement using the Arduino microcontroller and strain gauges devices’, Revista Brasileira de Ensino de Física, vol. 41.
Stacey, TR 1981, ‘A simple extension strain criterion for fracture of brittle rock’, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, vol. 18, pp. 469–474.
Takahashi, M & Koide, H 1989, ‘Effect of the intermediate principal stress on strength and deformation behaviour of sedimentary rocks at the depth shallower than 2000 m’, in V Maury & D Fourmaintraux (eds), Rock at Great Depth, vol 1, A.A. Balkema, Rotterdam, pp. 19–26
Takahashi, M, Narite, T & Tomishima, Y 2001, ‘Various loading systems for rock true triaxial compression test’, Journal of the Japan Society of Engineering Geology, vol. 42, no. 4, pp. 242–247 (in Japanese).
Wang, C 2018, Evolution, Monitoring and Predicting Models of Rockburst - Precursor Information for Rock Failure, Springer, Singapore,
Whyatt, JK, Blake, W, Williams, TJ & White, BG 2002, ‘Mining publication: 60 years of rockbursting in the Coeur D'Alene district of northern Idaho, USA: lessons learned and remaining issues’, Proceedings of the 109th Annual Exhibit and Meeting, Society for Mining, Metallurgy, and Exploration, Englewood.
Youwei, X, Shengshen, WU, Williams, DJ & Serati, M 2018, ‘Determination of peak and ultimate shear strength parameters of compacted clay’, Engineering Geology, vol. 243, pp. 160–167,
Zhu, X, Jin, X, Jia, D, Sun, N & Wang, Pu 2019, ‘Application of data mining in an intelligent early warning system for rock bursts’, Processes 2019, vol. 7, no. 55.

© Copyright 2020, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
Please direct any queries or error reports to