A Constitutive Model for Multi-Line Simulation of Granular Material Behavior Using Multi-Plane Pattern

Abstract

Problem statement: Improper understanding of material behavior prevents the efficient and correct usage of available materials and consequently, increases the construction and maintenance costs and even unsuitable construction. Considering the necessity of exact investigation about material behavior, several researches have been carried out in this field but the majority of these researches did not propose a general method for prediction of granular material behavior. Furthermore, many of the methods proposed by researchers are not able to present the properties such as the orientation of failure mechanism of propagating plasticity in materials. Approach: In this study, a general method was proposed for multi-laminate simulation to predict the behavior of materials. The general applicability of this method for prediction of granular material is one of its significant advantages. The study was carried out in the framework of multi-plane pattern which is able to predict anisotropic behavior, consider the effect of stress and strain axis rotations in plasticity, consider the semi-micro mechanical history and finally predict the orientation of failure mechanism. The method was presented in a matter that there is no limitation for different shapes of stress-strain curves. Results: It was concluded that using this method, fundamental properties of material such as material fracture, orientation of failure, anisotropic behavior of material, separation of behavior in several planes and rotation of principle axis of stress and strain during nonlinear behavior can be determined. Conclusion/Recommendations: This method can be used for complicated material behavior simulation under seismic loading, cyclic loading or fatigue effects. For future works, the method can be extended by increasing the number of planes. Higher-order equations can also be used to have a more accurate approximation of stress-strain curve.

Development of an elastoplastic constitutive model in the framework of the multilaminate method for numerical analyses of geotechnical structures

“…The basis of the multilaminate theory is to determine the numerical relationship between the two states of interparticle behavior (microscale behavior) and engineering mechanical properties (large-scale behavior) in the form of a constitutive equation. In other words, in this case, the material properties are obtained according to each of its components; and it could be possible to achieve the stress-strain relation of the soil by studying the interparticle behavior [6].…”

“…In this way, any change that occurs on the plane  is related to the point  . A plane is defined for each point in such a way that the direction cosines of the contact points are the same direction cosines perpendicular to the plane [6,20].…”

“…Another elastoplastic model based on multilaminate theory was presented by Sadrnejad and Pande [5] to predict sand behavior. Sadrnejad et al [6] Presented a Multi-Line constitutive model using a multilaminate model for granular soils. Zreid and Kaliske [7] presented a microplane plasticity model based on the Drucker-Praeger yield criterion.…”