Projects

Global production of concrete drives huge flows of material between natural and human systems.The shear magnitude of this material flow, which exceeds 12 billion tons each year, causes significant societal impacts. For example, concrete-based infrastructure projects require major investments of public capital, trigger enormous greenhouse gas emissions from cement production, and lead to construction-related traffic congestion resulting in pollution and lost productivity. These broad economic, environmental, and social consequences have largely been ignored in materials R&D. Development and application of new materials has focused almost exclusively on the interplay between material microstructure, physical properties, processing, and performance. This is a considerable shortcoming, particularly as new materials are sought to supplement or replace concrete given its inherent brittleness and limited durability.

Intellectual Merit:  The proposed research will address this shortcoming by developing a novel framework for sustainable design that integrates microstructure tailoring with life cycle analysis based on environmental, social, and economic indicators. This work encompasses multi-scale boundaries ranging from nanometers to kilometers, and multi-disciplinary perspectives including civil and materials engineering, geology, environmental health sciences, industrial ecology, environmental economics, and public policy. The research will consider the development and application of a new class of materials known as engineered cementitious composites (ECC). Its aim is to enhance the sustainability of bridge, road and pipe infrastructure using ECC. Among the issues to be explored are the impacts on sustainability performance of concrete replacement with ECC, material sourcing alternatives (e.g., superquarries vs. smaller mines), and location of infrastructure projects (e.g., urban vs. rural, and U.S. vs. China). Researchers will use results to recommend policy measures that facilitate the acceptance of new, more sustainable infrastructure materials. Given the inherent design complexity, they will incorporate uncertainty and sensitivity analysis to ensure that results are sufficiently robust to support effective decision-making.

Broader Impacts:  The integrated framework developed around ECC will be applicable to the design of many other emergent materials.  Interdisciplinary education and training will be fostered by including a number of student positions on the research team (2 postdoctoral, 3-5 doctoral, 2 undergraduate and 2 minority high school summer interns).  In addition, educational outreach will be facilitated through a web-based educational resource compendium, a MUSES seminar series, and regular team workshops.  The University of Michigan (UM) team will leverage results of the proposed research through three collaborations: the Fracture Research Institute, Tohoku University (Japan) will investigate the use of a CO2 hardening process on our new ECC mixes; Stanford University will conduct mechanical testing of these mixes for building applications; and the Building Material Research Laboratory, Tsinghua University will apply our life cycle models to assess sustainability performance of infrastructure systems in China. This research draws upon the diverse expertise and resources of a core network of seven UM faculty. Participating units include the Advanced Civil Engineering Material Research Lab, the Center for Sustainable Systems, College of Engineering, School of Public Health, School of Natural Resources and Environment, and the Department of Geological Sciences.  An external advisory group of industry, government and other key stakeholders will provide guidance on the direction of research to help identify opportunities for improvement over the five-year duration.