Evaluation of the effect of micro-parameters on the macroscopic properties of cemented granular soils

Document Type : Research Article


1 Geotechnic-civil engineering-Shahid Beheshti university-Tehran-Iran

2 P.O. 16765-1719 Tehran, Iran


One of the bonded contact models that is used to simulate the cemented bonds formed between soil particles in a cemented sample in the discrete element method is the "flat joint" model. There are numerous micro-parameters required to define this contact model between particles in the modeling and the effects of each of these parameters on the material response are not clear. In this research, after performing large-scale static and dynamic triaxial tests on cemented gravel in the laboratory, they were simulated as a granular assembly in which the flat joint contact model exists at all grain-grain contacts. Then, a sensitivity analysis was conducted to determine the effect of each micro-parameter on the macroscopic response of cemented samples and to specify the most impressive micro-parameters in order to simplify the calibration process. A regression analysis of the numerical results was performed to quantify the relationships between the micro-parameters and the mechanical properties of the sample. The results show that the maximum and residual shear strength of a sample are mainly dependent on the flat joint cohesion and stiffness ratio. The effects of elastic modulus and stiffness ratio on the initial tangential modulus and shear modulus are significant. The Poisson ratio is affected by the flat join cohesion and stiffness ratio. The damping ratio depends more on the elastic modulus. These results can be used as a guide for modeling the behavior of brittle materials in the discrete element method. A comparison between numerical and experimental test results of cemented granular specimens revealed that the model was able to capture the softening behavior of these materials with good accuracy.


Main Subjects

[1] E. Hoek, C. D. Martin, Fracture initiation and propagation in intact rock – A review, Journal of Rock Mechanics and Geotechnical Engineering, 6(4) (2014) 287–300.
[2] D. O. Potyondy, A flat-jointed bonded-particle material for hard rock. Proc., 46th U.S. Rock Mechanics/Geomechanics Symposium, Chicago, American Rock Mechanics Association, Alexandria, VA, (June 2012).
[3] B. Yang, Y. Jiao, S. Lei, A study on the effects of microparameters on macroproperties for specimens created by bonded particles, Engineering Computations, 23(6) (2006) 607-631.
[4] J. Yoon, Application of experimental design and optimization to PFC model calibration in uniaxial compression simulation, International Journal Rock Mechanics and Mining Sciences, 44(6) (2007) 871–889.
[5] A. S. Tawadrous, D. DeGagnã, M. Pierce, D. M. Ivars, Prediction of uniaxial compression PFC3D model micro-properties using artificial neural networks, International Journal for Numerical and Analytical Methods in Géoméchanics, 33(18) (2009) 1953–1962.
[6] K. J. Hanley, C. O’Sullivan, J. Oliveira, K. Cronin, E.P. Byrne, Application of Taguchi methods to DEM calibration of bonded agglomerates, Powder Technology, 210(3) (2011) 230–240.
[7] L. Cheung, C. O’Sullivan, M. Coop, Discrete element method simulations of analogue reservoir sandstones, International Journal of Rock Mechanics and Mining Science, 63 (2013) 93–103.
[8] M. Sun, H. Tang, X. Hu, Y. Ge, S. Lu, Microparameter prediction for a triaxial compression PFC3D model of rock using full factorial designs and artificial neural networks, Geotechnical and Geological Engineering, 31 (2013) 1249–1259.
[9] X. Ding, L. Zhang, H. Zhu, Q. Zhang, Effect of model scale and particle size distribution on PFC3D simulation results, Rock Mechanics and Rock Engineering, 47 (2013) 2139–2156.
[10] P. Y. Chen, Effects of microparameters on macroparameters of flat-jointed bonded-particle materials and suggestions on trial-and-error method, Geotechnical and Geological Engineering, 35(2) (2017) 663-677.
[11] Q. Zou, B. Lin, Modeling the relationship between macro- and meso-parameters of coal using a combined optimization method, Environmental Earth Sciences., 76 (2017) 479–498.
[12] M. Wang, P. Cao, Calibrating the micromechanical parameters of the PFC2D(3D) models using the improved simulated annealing algorithm, Mathematical Problems in Engineering, (2017) 1–11.
[13] C. Zhou, C. Xu, M. Karakus, J. Shen, A systematic approach to the calibration of micro-parameters for the flat-jointed bonded particle model, Geomechanics and Engineering, 16(5) (2018) 471-482.
[14] U. Castro-Filgueira, L.R. Alejano, J. Arzúa, D.M. Ivars, Sensitivity analysis of the micro-parameters used in a PFC analysis towards the mechanical properties of rocks, ISRM European Rock Mechanics Symposium- EUROCK 2017, Ostrava, Czech Republic, (June 2017), 191:488–495.
[15] C. Shi, W. Yang, J. Yang, X. Chen, Calibration of micro-scaled mechanical parameters of granite based on a bonded-particle model with 2D particle flow code, Granular Matter, 21 (2019) 38-50.
[16] Itasca Consulting group Inc. Particle Flow Code in Three Dimensions (PFC3D) (2018) Version 6.00. Minneapolis, USA.
[17] S. Wu, X. Xu, A study of three intrinsic problems of the classic discrete element method using flat-joint model, Rock Mechanics and Rock Engineering, 49(5) (2016) 1813-1830.
[18] J. A. Vallejos, J. M. Salinas, A. Delonca, D. Mas Ivars, Calibration and verification of two bonded-particle models for simulation of intact rock behavior, International Journal of Geomechanics, 17(4) (2017) 1-11.
[19] M. Bahaaddini, A. M. Sheikhpourkhani, H. Mansouri, Flat-joint model to reproduce the mechanical behaviour of intact rocks, European Journal of Environmental and Civil Engineering, (2019) 1-22.
[20] H. Wu, B. Dai, G. Zhao, Y. Chen, Y. Tian, A novel method of calibrating micro-scale parameters of PFC model and experimental validation, Applied Sciences, 10(9) (2020) 1-20.
[21] S. Yu, M. Jia, J. Zhou, C. Zhao, L. Li, Micro-Mechanism of spherical gypsum particle breakage under ball–plane contact condition, Applied Sciences, 9(22) (2019) 1-16.