Document Type : Original Research Paper

Authors

1 Department of Mining Engineering, Hamedan University of Technology, Hamedan, Iran

2 Rahsazi and Omran Iran construction Company, Tehran, Iran

3 Faculty Mining and Matallurgical Engineering, Yazd University, Yazd, Iran

Abstract

The tensile strength of the anisotropic rock-like material specimens is meastred directly in the laboratory using a new device converting the compressive loading to that of the tensile before the rock breakage. The specially prepared concrete slabs of dimensions 19 cm * 15 cm * 15 cm with a central hole of 7.5 cm in diameter are tested experimentaly. The specimens are located in the compressive-to-tensile load converting device, and tested under a compressive loading rate of 0.02 MPa/s by the universal testing machine. The cubic slab samples are made in three different configurations to have the directions of  0°, 45°, and -45° with respect to the applied loading direction. In order to compare the direct tensile strength of the concrete samples with that of the indirect measuring tests, some Brazilian tests are also carried out on the concrete disc specimens prepared in the laboratory. By comparing the direct and indirect testing results of the concrete tensile strength, it can be concluded that the direct tensile strength values are somewhat lower than those of the indirect ones. The tensile strength values for the three different configurations of the concrete specimens are nearly the same.

Keywords

[1]. Bieniawski, Z.T. and Hawkes, I. (1978). International Society for Rock Mechanics Commission on Standardization of Laboratory and Field tests suggested methods for determining tensile-strength of rock materials.
[2]. Zhang, Z.X. (2002). An empirical relation between mode I fracture toughness and the tensile strength of rock. International journal of rock mechanics and mining sciences. 39 (3): 401-406.
[3]. Martin, C.D. (2014). The direct and Brazilian tensile strength of rock in the light of size effect and bimodularity. In 48th US Rock Mechanics/Geomechanics Symposium. American Rock Mechanics Association.
[4]. Liu, Y.I., Dai, F., Xu, N., Zhao, T., and Feng, P. (2018). Experimental and numerical investigation on the tensile fatigue properties of rocks using the cyclic flattened Brazilian disc method. Soil Dynamics and Earthquake Engineering, 105, 68-82.
[5]. Shang, J., Duan, K., Gui, Y., Handley, K., and Zhao, Z. (2018). Numerical investigation of the direct tensile behaviour of laminated and transversely isotropic rocks containing incipient bedding planes with different strengths. Computers and Geotechnics. 104: 373-388.
[6]. Liao, Z.Y., Zhu, J.B., and Tang, C.A. (2019). Numerical investigation of rock tensile strength determined by direct tension, Brazilian and three-point bending tests. International Journal of Rock Mechanics and Mining Sciences. 115: 21-32.
[7]. Aliabadian, Z., Zhao, G.F., and Russell, A.R. (2019). Failure, crack initiation and the tensile strength of transversely isotropic rock using the Brazilian test. International Journal of Rock Mechanics and Mining Sciences. 122: 104073.
[8]. Bernie Gorski, Blain Conlon, 2007. Determination of the direct and indirect tensile strength on cores from borehole KFM01D, CANMET-MMSL, Mining and Mineral Sciences Laboratories, Natural Resources Canada, pp.07-76.
[9]. Wang, Q.Z., Jia, X.M., Kou, S.Q., Zhang, Z.X., and Lindqvist, P.A. (2004). The flattened Brazilian disc specimen used for testing elastic modulus, tensile strength and fracture toughness of brittle rocks: analytical and numerical results. International Journal of Rock Mechanics and Mining Sciences. 41(2): 245-253.
[10]. Ghaffar, A., Chaudhry, M.A., and Ali, M. K. (2005). A new approach for measurement of tensile strength of concrete. Journal of Research (Science). 16 (1): 1-9.
[11]. Erarslan, N., and Williams, D. J. (2012). Experimental, numerical and analytical studies on tensile strength of rocks. International Journal of Rock Mechanics and Mining Sciences. 49: 21-30.
[12]. Wei, X.X., and Chau, K.T. (2013). Three dimensional analytical solution for finite circular cylinders subjected to indirect tensile test. International Journal of Solids and Structures. 50 (14-15): 2395-2406.
[13]. Kim, J.J., and Reda Taha, M. (2014). Experimental and numerical evaluation of direct tension test for cylindrical concrete specimens. Advances in Civil Engineering, 2014.
[14]. Zhou, F.P. (1988). Some aspects of tensile fracture behaviour and structural response of cementitious materials.
[15]. Silva, R.V., De Brito, J., and Dhir, R.K. (2015). Tensile strength behaviour of recycled aggregate concrete. Construction and Building Materials. 83: 108-118.
[16]. Silva, R.V., De Brito, J., and Dhir, R.K. (2015). Tensile strength behaviour of recycled aggregate concrete. Construction and Building Materials. 83: 108-118.
[17]. Abrishambaf, A., Barros, J.A., and Cunha, V.M. (2015). Tensile stress–crack width law for steel fibre reinforced self-compacting concrete obtained from indirect (splitting) tensile tests. Cement and Concrete Composites. 57: 153-165.
[18]. Saridemir, M. (2016). Empirical modeling of flexural and splitting tensile strengths of concrete containing fly ash by GEP. Computers and Concrete. 17 (4): 489-498.
[19]. Li, S., Wang, H., Li, Y., Li, Q., Zhang, B., and Zhu, H. (2017). A new mini-grating absolute displacement measuring system for static and dynamic geomechanical model tests. Measurement. 105: 25-33.
[20]. Zhang, D., Hou, S., Bian, J., and He, L. (2016). Investigation of the micro-cracking behavior of asphalt mixtures in the indirect tensile test. Engineering Fracture Mechanics. 163: 416-425.
[21]. Alhussainy, F., Hasan, H.A., Rogic, S., Sheikh, M.N., and Hadi, M.N. (2016). Direct tensile testing of self-compacting concrete. Construction and Building Materials. 112: 903-906.
[22]. Ayatollahi, M.R., Pirmohammad, S., and Sedighiani, K. (2014). Three-dimensional finite element modeling of a transverse top-down crack in asphalt concrete. Computers and Concrete. 13 (4): 569-585.
[23]. Omar, H., Ahmad, J., Nahazanan, H., Mohammed, T.A., and Yusoff, Z.M. (2018). Measurement and simulation of diametrical and axial indirect tensile tests for weak rocks. Measurement. 127: 299-307.
[24]. Tran, K.Q., Satomi, T., and Takahashi, H. (2019). Tensile behaviors of natural fiber and cement reinforced soil subjected to direct tensile test. Journal of Building Engineering. 24: 100748.
[25]. ASTM, D. (2008). 2936-08. Standard test method for direct tensile strength of intact rock core specimens. Annual Book of ASTM Standards. 4: 08.
[26]. Nianxiang, X., and Wenyan, L. (1989). Determining tensile properties of mass concrete by direct tensile test. Materials Journal. 86 (3): 214-219.
[27]. Zheng, W., Kwan, A.K.H., and Lee, P.K.K. (2001). Direct tension test of concrete. Materials Journal. 98 (1): 63-71.
[28]. Hannant, D.J., and DJ, H. (1972). The tensile strength of concrete: a review paper.
[29]. Chen, W.F., and Trumbauer, B.E. (1972). Double-punch test and tensile strength of concrete. Journal of Materials, 7 (2).
[30]. Swaddiwudhipong, S., Lu, H. R., and Wee, T.H. (2003). Direct tension test and tensile strain capacity of concrete at early age. Cement and concrete research. 33 (12): 2077-2084.
[31]. Zain, M.F.M., Mahmud, H.B., Ilham, A., and Faizal, M. (2002). Prediction of splitting tensile strength of high-performance concrete. Cement and Concrete Research. 32 (8): 1251-1258.
[32]. Bui, N. K., Satomi, T., and Takahashi, H. (2018). Mechanical properties of concrete containing 100% treated coarse recycled concrete aggregate. Construction and Building Materials. 163: 496-507.
[33]. ASTM D3967-16, Standard Test Method for Splitting Tensile Strength of Intact Rock Core Specimens, Annual Book of ASTM Standards, Vol. 4, ASTM, West Conshohocken, PA.