Modeling of high-rate hardening of a polymer composite material under loading along the reinforcement direction

Modeling the high-rate deformation of composite structures is of great interest in the industry. Moreover, some processes such as accidents, explosions and possible impact issues require analysis of composite materials at significantly high deformation rates. The paper considers the possibility of developing a model of deformation of a composite material based on a polymer matrix and carbon fiber taking into account high-rate hardening. A feature of the study is the development of a model that takes into account a wide range of deformation rates from static to several thousand reverse seconds. Thus, tests were carried out with special equipment and samples that allow us to obtain data with such high loading speeds. The model is based on an approach considering the use of damage parameters, the so-called class of models with progressive degradation. The main innovative part of the chosen model is the formalization of the rate of deformation on the material through the damage parameter, that is, the rate of change in damage values is considered. This approach makes it possible to make constitutive relations based only on the damage parameters, which modify the stiffness and strength characteristics of composites, which greatly simplifies the modeling and analysis of material deformation.