Seminar | Robert Buarque de Macedo: Impact of Particle Shape on Granular Mechanics

Join us Oct. 27 for a seminar with Robert Buarque de Macedo of Sandia National Laboratories on how particle shape influences granular mechanics, from ant tunnel stability to engineered materials and shock propagation.

Abstract

Granular materials are any collection of discrete, solid particles. Granular materials exist throughout nature at many scales, from the micro-scale (powers and soils) to rocks and boulders, and even at the cosmic scale (asteroids). In this talk, we study a range of problems in granular mechanics. First, excavation in granular materials is considered. It is studied how ants can so successfully manipulate granular materials to achieve stable systems by mapping the forces around real ant tunnels. Ant tunnels are simulated using a DEM which can handle arbitrary shaped grains: the Level-Set Discrete Element Method (LS-DEM). Next, we consider design of granular materials by controlling grain shape. Here, tools are developed for controlling mesoscopic attributes of granular materials as a function of grain shape. To do so, genetic algorithms and a deep generative model are combined with LS-DEM. Finally, we explore a practical application of granular design by investigating how grain morphology affects the behavior of shock propagating through particulates. 

Bio

Robert Buarque de Macedo is a senior member of technical staff at Sandia National Laboratories Albuquerque in the Materials and Failure Modeling department. He completed his Bachelor of Science in physics from Carnegie Mellon University in 2017 and his Master of Science and Ph.D. in applied mechanics from Caltech in 2019 and 2023, respectively. He has been affiliated with Sandia ever since graduating Caltech.