A Computational Constitutive Model for Glass Subjected to Large Strains, High Strain Rates and High Pressures

Abstract

A Computationai Constitutive Modei for Giass Subjected to Large Strains, High Strain Rates and High PressuresThis article presents a computational constitutive model for f^la.ss subjected to large strains, high strain rates and high pressures. The model has similarities to a previottsly developed model for brittle materials by Johnson. Holmquist and Beissel (JHB model), hut thete ate significatit differences. This new glass model provides a material sttength that is depetulent on the location and/or condition of the matetial. Ptovisions are made for the .sttength to be depetidetit on whether it is in the intetior, on the sutface (different sutface finishes can be accommodated), adjacent to failed material, or if it is failed. The intact and failed sttengths are also dependetit on the pressure atid the strain täte. Tlietmal softening, damage softening, time-dependent softening, and the effect of the third invariant are also inchided. The shear modttlus can be constant or variable. The pressure-vohtme relationship includes permanent densification and bulking. Damage is accumulated based on plastic strain, ptessure and strain täte. Simple (sitigle-element) e.xamples are presented to illusttate the capabilities of the model. Compttted results for more complex ballistic impact configttrations are also ptesented atid compared to expetitnental data.

Modifications of RHT material model for improved numerical simulation of dynamic response of concrete

“…Recent advancements saw the development of several comprehensive concrete models that are aimed at high-impulsive load applications, with consideration of such effects as pressure hardening, strain hardening, material softening and rate-dependency. Models of this category include the RHT model [1, 9,10], the K&C model [11,12] and JHC concrete model [13].…”

Dynamic behavior of an aggregate material at simultaneous high pressure and strain rate: SHPB triaxial tests

“…Many behavior models for these materials take the strain rate dependence into account [35]. As an example, the model of Holmquist et al [36] is well-known and used for computation of concrete structure under dynamic loading. In the yield function (9), the strain rate is introduced using the following relations:…”

Brittle materials at high-loading rates: an open area of research

“…Among the constitutive models developed to numerically simulate the response of brittle materials are the modified version of the HJC model (MHJC) [54] inspired by the Holmquist-Johnson-Cook (HJC) model [55] which is applied to numerically simulate a drill bit drop test against Kuru granite rock [16]. Furthermore, an improved model is proposed for glass that represents both its interior and surface strength so that the numerical approach can be used to simulate single or multi hit situations for transparent windshields [56].…”