Implicit integration of incrementally non-linear, zero- elastic range, bounding surface plasticity. (August 2019)

• Record Type: Journal Article
• Authors: Petalas, Alexandros L.; Dafalias, Yannis F.
• Is Part Of: Computers and geotechnics. Volume 112(2019)
• Page Start: 386
• Page End: 402
• Publication Date: 2019-08
• Subjects: Implicit integration -- Incrementally non-linear -- Bounding surface; Engineering geology -- Data processing -- Periodicals; Soil mechanics -- Data processing -- Periodicals; Rock mechanics -- Data processing -- Periodicals; 624.1510285
• DOI: 10.1016/j.compgeo.2019.04.009
• Languages: English
• ISSNs: 0266-352X

Abstract

Abstract: The zero elastic range, bounding surface plasticity framework is a suitable choice for modeling materials which exhibit zero purely elastic response during shearing. As a consequence of zero elastic range the plastic strain increment direction, and consequently the elastic-plastic moduli fourth order tensor depends on the direction of the stress increment, rendering the model incrementally non-linear. The system of ordinary differential equations of the elastic-plastic formulation is intrinsically implicit. Thus, an iterative algorithm based on the Backward Euler numerical integration method and the damped Newton-Raphson method with an adaptive trial step is proposed in this work. The proposed methodology is applied to the zero elastic range SANISAND-Z model for sands and a thorough verification is done for various applied strain histories. The proposed integration scheme allows the use of SANISAND-Z or any other bounding surface zero elastic range model in displacement-driven finite element analysis.