AMS Seminar: Lori Brady (JHU-Civil Eng) @ Whitehead 304

Title: Uncertainty propagation in mechanics and materials by design based on surrogate model development
Abstract: With the onset of advanced manufacturing capabilities and in situ characterization techniques, simultaneous material/structural design is becoming increasingly feasible for maximum structural performance. At the heart of such design processes is the availability of multi-scale mechanics models that incorporate explicit representation of the material (such as microstructural descriptors) and the structure (such as the geometry). A major challenge here is that a full physically-based multi-scale model is often computationally infeasible. Surrogate functions that provide a simplified representation of the material provide a much more efficient alternative. Such surrogate functions also enable a quantification of the propagation of uncertainties between scales. While these surrogate functions do increase efficiency, they lead to a number of associated challenges. If the material is represented by a large number of microstructural parameters, then the high dimensionality of the surrogate function requires many samples in order to build an accurate surrogate. Furthermore, some micro-scale behavior, such as sudden damage, can lead to discontinuities in the surrogate function, which makes it difficult to interpolate or collocate the results. This seminar will describe a number of approaches to building surrogates, including cases in which the micro-scale model provides key response values and/or gradients of key response values.