Designing Random Heterogeneous Construction Materials for Fracture Resistance

Abstract: The spatial arrangement of random heterogeneous materials such as concrete, rock, and polymer composites are often overlooked in the study of their mechanical properties. In the context of civil engineering materials, a study of material spatial arrangement can enable novel design, manufacturing, and performance assessment of randomly structured materials. This seminar presents research work aiming to explore the theoretical link between material spatial statistics and toughness. The first study presents a theoretical and experimental study of rock arrangements in concrete beams showing that toughness correlates to the degree of inclusion order. Next a theoretical study is presented which finds that particle spatial arrangement metrics derived from the translational order parameter and bond-orientational order parameter show correlations to near-crack-tip stress fields. Motivated by these correlations two material design applications are discussed: controlling rock arrangement in concrete by raking of rocks and the design of a biomaterial-based alternative to concrete optimized for toughness.

Bio: Mija H. Hubler received her B.S. in structural engineering from the University of Illinois at Urbana-Champaign, her M.S. from Cornell University, and her Ph.D. from Northwestern University. She is currently an associate professor at the University of Colorado, Boulder. She is the chair of ACI 209 Committee on Creep and Shrinkage of Concrete and ASCE EMI’s Experimental Analysis and Instrumentation Committee. Her research has been recognized with the Leonardo Da Vinci Award from the Experimental Mechanics Institute, the Gustavo Colonnetti Medal from RILEM, and an NSF Early Career Award. Her research interests include aging of construction materials, concrete infrastructure design and construction methods, and the design of alternative construction materials from biological elements and engineered waste materials.

Seminars are held on select Wednesdays from 12:00 noon-1pm, Eastern/New York time.

A light lunch is provided at 11:30 a.m. in the Bowen Hall Atrium immediately prior to the seminar.