A new constitutive model for simulation of softening, plateau, and densification phenomena for trabecular bone under compression. (January 2017)

• Record Type: Journal Article
• Authors: Lee, Chi-Seung; Lee, Jae-Myung; Youn, BuHyun; Kim, Hyung-Sik; Shin, Jong Ki; Goh, Tae Sik; Lee, Jung Sub
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 65(2017)
• Page Start: 213
• Page End: 223
• Publication Date: 2017-01
• Subjects: Trabecular bone -- Material nonlinearity -- Constitutive model -- Finite element analysis -- Computational inelasticity -- ABAQUS user-defined subroutine UMAT; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2016.08.028
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: A new type of constitutive model and its computational implementation procedure for the simulation of a trabecular bone are proposed in the present study. A yield surface-independent Frank–Brockman elasto-viscoplastic model is introduced to express the nonlinear material behavior such as softening beyond yield point, plateau, and densification under compressive loads. In particular, the hardening- and softening-dominant material functions are introduced and adopted in the plastic multiplier to describe each nonlinear material behavior separately. In addition, the elasto-viscoplastic model is transformed into an implicit type discrete model, and is programmed as a user-defined material subroutine in commercial finite element analysis code. In particular, the consistent tangent modulus method is proposed to improve the computational convergence and to save computational time during finite element analysis. Through the developed material library, the nonlinear stress–strain relationship is analyzed qualitatively and quantitatively, and the simulation results are compared with the results of compression test on the trabecular bone to validate the proposed constitutive model, computational method, and material library.