A model-based simulation tool for impact/blast-resistant structural design.

摘要

Two major issues are to be considered in the numerical analysis of impact/blast events. One is the need for a suitable material characterization in terms of the constitutive models under high strain rates, since the structural failure due to such events involves plasticity, damage, localization, thermal softening, phase transition and fragmentation. The other is that a robust spatial discretization method is a necessity for large-scale simulation of multi-physical phenomena involved in such events.; In order to fulfill these requirements, a model-based simulation tool for impact/blast-resistant structural design is developed. A solution scheme, in which a rate-dependent local continuum damage/plasticity model is combined with a rate-dependent decohesion model via the discontinuous bifurcation analysis, has been implemented to simulate the impact failure of concrete. A computational algorithm, in which the fluid-structure interaction under impact/blast loading can be simulated without interface treatment within a single computational domain, has been provided based on the Material Point Method. A coupled rate-dependent plasticity and damage model for quasi-brittle materials under impact loading with a focus on compression has been developed based on the thermodynamic restrictions with a rate-dependent continuum tangent stiffness tensor derived for the discontinuous bifurcation analysis.; The dissertation addresses these important topics in the field of computational science and mechanics, and provides a fundamental work for the establishment of the computer test-bed for impact/blast-resistant structural design.