Abstract. Replacing prototype testing by computer simulation is essential for speeding design cycle times. Since a critical requirement in any design is to prevent failure without incurring high cost, the ability to simulate failure is vital in this paradigm shift. For the last few years, several types of computational failure analysis methods have been developed. However, computational modeling of failure and reliable predictions are still highly problematic and one of the biggest challenges in computational mechanics. The primary motivation of this talk is to introduce recently developed XFEM-based computational failure analysis methods that can model arbitrary crack growths independent from the initial mesh topologies. The first part of this talk will present key concepts in these methods along with various dynamic failure analysis results in shell and 3D models under extreme dynamic loading or fluid-structure interaction induced loading conditions.

In the second part, a new multi-scale analysis method for predicting multi-scale failure will be described. Particular emphasis will be placed on the situation where the coarse scale model loses its ellipticity, which is always the case with failure. A new method for treating that situation will be described within the context of multi-scale approaches. Its notable feature is the decomposition of the unit cell response into a discontinuity and a smooth response. Two key concepts are fundamental to the development of this method: the notion of a perforated unit cell that excludes all material that is not strictly convex and a method for extracting the discontinuity at the macro-scale from the micro-scale response. The methods are combined with the XFEM for the coarse scale model, so that arbitrary discontinuities at the macroscale can be treated. We will conclude this talk with examples for mechanical study of multi-scale failure analysis to examine the applicability of this multi-scale failure analysis method.

Bio. Dr. Jeong-Hoon Song received his B.S. and M.S. from the Department of Civil Engineering at Yonsei University, Korea, and Ph.D. from Theoretical and Applied Mechanics, Northwestern University. Dr. Song has worked on developing high fidelity computational failure analysis frameworks focusing on predicting static/fatigue/dynamic fracture in micro/macro scales, fluid-structure interactions, and multiscale failure behaviors.