M. Tashkinov et alii, Frattura ed Integrità Strutturale, 49 (2019) 396-411; DOI: 10.3221/IGF-ESIS.49.39 396 Focused on Russian mechanics contributions for Structural Integrity Computational multi-scale analysis of simultaneous processes of delamination and damage accumulation in laminated composites Mikhail Tashkinov, Daria Ershova, Aleksandr Shalimov Perm National Research Polytechnic University, Russia m.tashkinov@pstu.ru, http://orcid.org/0000-0003-4660-0020 daria.yershova@yandex.ru, https://orcid.org/0000-0001-5023-7186 neilcrite@gmail.com, https://orcid.org/0000-0002-8729-6144 ABSTRACT. When studying mechanical behavior of structures made of laminated polymer composite materials, issues related to their relatively high susceptibility to damage, such as delamination, fiber breakage and matrix failure, play significant role. Key aspects are also related to accurate description of the internal structures and heterogeneity of the material. This work is aimed at a numerical study of the processes of damage accumulation in plies as well as development of delamination in laminated polymer composite L-shaped specimen taking into account microstructural parameters. The influence of contact conditions between the plies on the model’s behavior has been studied. It was established that the delamination processes inside the specimen can initiate at the early stages of deformation, which is reflected in the difference of the results obtained using models with various numbers of separated plies. Comparison of the results of modelled elastic behavior of the specimen and models with the developed delamination leads to conclusions about influence of a number of model parameters on the results obtained before and after propagation of delamination. In particular, such factors as the geometry and mechanical properties of models, the number and conditions for specifying contact pairs in the model were analyzed. KEYWORDS. Composite laminates; Delamination; VCCT; Progressive failure analysis; Fracture criteria. Citation: Tashkinov, M., Ershova, D., Shalimov, A., Computational multi-scale analysis of simultaneous processes of delamination and damage accumulation in laminated composites, Frattura ed Integrità Strutturale, 49 (2019) 396-411. Received: 02.04.2019 Accepted: 14.06.2019 Published: 01.07.2019 Copyright: © 2019 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. INTRODUCTION he difficulties in modeling of failure of laminated composite structures are related to the inhomogeneities of microstructure of composite materials. A characteristic feature of laminated polymer composites is that the origin of the fracture processes in the material does not always lead to complete failure of the structure. Thus, until the structural integrity is lost, damage can be accumulated at various scale levels. T