Identification of material parameters for numerical simulation of the behavior of rocks under true triaxial conditions

User Rating:  / 0
PoorBest 

Authors:

I.G.Sakhno, Dr. Sc. (Tech.), Assoc. Prof., orcid.org/0000-0002-8592-0572, State Higher Educational Institution “Donetsk National Technical University”, Pokrovsk, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

А.V.Molodetskyi, Cand. Sc. (Tech.), orcid.org/0000-0002-8457-9640, Institute for Physics of Mining Processes National Academy of Sciences of Ukraine, Dnipro, Ukraine

S.V.Sаkhno, orcid.org/0000-0003-3917-9143, State Higher Educational Institution “Donetsk National Technical University”, Pokrovsk, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract:

Purpose. Development a modified model of geomaterials for numerical simulation of the behavior of rocks in a true triaxial stress field.

Methodology. The research was conducted on specimens of coal grade “С”. Input parameters of materials for basic models in the modeling by the finite element method were taken from the physical experiment. The experiment was conducted on the installation of true triaxial compression. The results of comparative studies on the behavior of rocks in the true triaxial stress field using the experimental method and numerical mathematical modeling are presented. Modeling is conducted by the finite element method in Ansys Inc software. The results of tests on the strength of coal specimens in generalized compression conditions are taken as in-situ properties.

Findings. It is established that use of classical deformation models – the elastic model and Drucker–Prager model – with numerical mathematical modeling of geomechanical processes is in error when describing the behavior of geomaterials in a volumetric field of stress of 30–15 % relative to the experiment. In this case, modeling with the use of an elastic model does not only cause a significant quantitative error, but also fails to reflect the quality of the dependence of the Young module and the volume compression module on average stresses at all stages of the strain. To adequately imitate the model of geomaterials, one must take into account the anisotropy of the elastic modulus, the shear modulus and the coefficient of transverse deformation, as well as the functional dependence of the dilation from the plastic deformation and the coefficient of rigidity.

Originality. The Drucker–Prager model was modified by taking into account the anisotropy of coal properties. Depending on the “average stress-average deformation”, the calculation error for the elastic model is 33 %, for the Drucker-Prager model it is 15 %, while for the modified Drucker–Prager model it is 0.14 %.

Practical value. Using the results of the study can improve the accuracy of the prediction the stress-strain state of geomechanical objects.

References.

1. Yasitli, N. E. and Unver, B., 2005. 3D Numerical Modeling of Longwall Mining with Top-Coal Caving. International Journal of Rock Mechanics and Mining Sciences, 42(2), pp. 219–235. DOI: 10.1016/j.ijrmms.2004.08.007.

2. Cheng, Y. M., Wang, J. A., Xie, G. X. and Wei, W. B., 2010. Three-Dimentional Analysis of Coal Barrier Pillars in Tailgate Area Adjacent to the Filly MechAnized Top Coal Caving Mining Face. International Journal of Rock Mechanics and Mining Sciences, 47, pp. 1372–1383. DOI: 10.1016/j.ijrmms.2010.08.008.

3. Yavuz, H., 2004. An Estimation Method for Cover Pressure Re-establishment Distance and Pressure Distribution in the Goaf of Longwall Coal Mines. International Journal of Rock Mechanics and Mining Sciences, 41, pp. 193–205. DOI: 10.1016/S1365-1609(03)00082-0.

4. Ju, M., Li, X., Yao, Q., Li, D., Chong, Z. and Zhou, J., 2015. Numerical investigation into effect of rear barrier pillar on stress distribution around a longwall face. Journal of Central South University, 22(11), pp. 4372–4384. DOI: 10.1007/s11771-015-2986-8.

5. Sakhno, I. G., 2012. Numeral design of geomechanical processes taking into account their non-linearity, Ground control in mining, 20–21, pp. 57–67. Available at: <http://ea.donntu.edu.ua/bitstream/123456789/26465/1/%d0%a1%d0%b0%d1%85%d0%bd%d0%be.pdf> [Accessed 05 November 2017].

6. Murakami, A., Arimoto, S., Setsuyasu, T. and Nishiyama, T., 2005. Mesh-Free Method for Predicting the Behavior of Saturated Soil. In: Geomechanics. Testing, Modelling, and Simulation. pp. 664–672. DOI: 10.1061/40797(172)39.

7. Ceccato, Fr. and Simonini, P., 2016. Granular Flow Impact Forces on Protection Structures: MPM Numerical Simulations with Different Constitutive. Models Procedia Engineering, 158, pp. 164–169. DOI: 10.1016/j.proeng.2016.08.423.

8. Robert, D. J., Soga, K. and Britto, A.M., 2015. Soil Constitutive Models to Simulate Pipeline-soil Interaction Behaviour. In:International Conference on Geotechnical Engineering ICGE Colombo. pp. 347–350.

9. Zhu, W. C. and Tang, C. A., 2004. Micromechanical model for simulating the fracture process of rock. Rock Mechanics and Rock Engineering, 37(1), 25–56.

10. Jaime, M. C., Zhou, Y., Lin, J.-S. and Gamwo, I. K., 2015. Finite element modeling of rock cutting and its fragmentation process. International Journal of Rock Mechanics and Mining Sciences, 80, pp. 137–146.

11. Öztekin, E., Pul, S. and Hüsem, M., 2016. Experimental determination of Drucker-Prager yield criterion parameters for normal and high strength concretes under triaxial compression. Construction Building Materials, 112, pp. 725–732.

12. Jiang, J-F. and Wu, Yu-F., 2012. Identification of material parameters for Drucker–Prager plasticity model for FRP confined circular concrete columns. International Journal of Solids and Structures, 49(3–4), pp. 445–456. DOI: 10.1016/j.ijsolstr.2011.10.002.

13. Karabinis, A. I. and Rousakis, T. C., 2002. Concrete confined by FRP material: a plasticity approach. Engineering Structures,24, pp. 923–932. DOI: 10.1016/S0141-0296(02)00011-1.

14. Molodetskyi, A. V. and Codeberg, D. S., 2011. Mechanical characteristics of coal at different types of stress state, Transactions of Kremenchuk Mykhailo Ostrohradskyi National University, 4(69), pp. 107–110. Available at: <http://www.kdu.edu.ua/statti/2011-4-1(69)/107.pdf> [Accessed 24 October 2017].

15. Sergienko, L. V., Gladkaya, E. V. and Molodet­skyi, A. V., 2015. Analysis of coal breaking mechanism under the conditions modelling stress-and-strain state of an accompanying-bed while in of mining work, Geotechnical Mechanics, 124, рр. 106–114.

 повний текст / full article

Visitors

4180690
Today
This Month
All days
6249
27858
4180690

Guest Book

If you have questions, comments or suggestions, you can write them in our "Guest Book"

Registration data

ISSN (print) 2071-2227,
ISSN (online) 2223-2362.
Journal was registered by Ministry of Justice of Ukraine.
Registration number КВ No.17742-6592PR dated April 27, 2011.

Contacts

D.Yavornytskyi ave.,19, pavilion 3, room 24-а, Dnipro, 49005
Tel.: +38 (056) 746 32 79.
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
You are here: Home Archive by issue 2018 Contents №5 2018 Solid State Physics, Mineral Processing Identification of material parameters for numerical simulation of the behavior of rocks under true triaxial conditions