CAREER: Increasing Resiliency and Sustainability of Reinforced Concrete against Aging and Seismic Hazards through Novel Materials

University Of Southern California, Los Angeles CA

Investigators

Abstract

This Faculty Early Career Development (CAREER) Program grant will investigate the combined effects of environmental aging and earthquakes on concrete bridges. The main cause of aging-induced deterioration in concrete bridges is corrosion of reinforcing bars, which may result in a significant reduction in load capacity and endanger the safety of the structure. An in-depth computational-experimental research program will be conducted to understand the main corrosion-related degradation mechanisms in reinforced concrete and potential impacts of earthquakes on the deteriorated bridge structure. Novel engineering materials of high-performance fiber-reinforced concrete and superelastic steel alloys will be employed to increase resiliency of the bridge members. The outcomes of this project are expected to result in direct benefits to the society by extending the lifetimes of bridge structures and by reducing the repair and maintenance costs. It is expected that the evaluation, prediction, and design tools developed in this project will serve as a basis for future research and implementation, in not only bridges but also in other reinforced concrete structures such as ports. The research and education will be integrated by creating a community with university researchers and with high school teachers and their students. The Investigator plans to engage college students from underrepresented groups in the project. High-performance fiber-reinforced concrete exhibits high crack tightness, increased tensile ductility, low permeability, and higher damage resistance compared with traditional concrete. Novel Cu-Al-Mn superelastic alloy reinforcing bars can recover large strains upon unloading. In addition, they are easily machinable and have a cost advantage over conventional superelastic alloy bars. Through use of these new materials, the objective of this project is to improve the seismic performance and durability of bridge structural elements. New knowledge will be generated on the deterioration processes of concrete structures, the thermo-mechanical behavior of new superelastic alloys, and the seismic response of deteriorated bridges.