Concrete inFocus - Spring 2013 - (Page OC1) infocus online connections Taking It to the Streets Transferring MIT Concrete Sustainability Hub Research into Practice Julie Garbini A s we embark on our fourth year of work at the Massachusetts Institute of Technology (MIT) Concrete Sustainability Hub (CSH), we can look back at several significant breakthroughs that have come out of the initial phases of work. These include: • The importance of the operating or “use” phase in life cycle assessment (LCA) of both pavements and structures; • Development of a mechanistic model to evaluate interaction between vehicles and pavement—the biggest factor in the LCA operating phase of pavements; and • The importance of considering materialspecific inflation rates when performing life cycle cost analysis (LCCA) to understand the risk associated with project decisions. To illustrate the significance of these breakthroughs, here are some specific research findings: Pavements • The use and rehabilitation phases account for 33 to 44 percent of the CO2e emissions for interstate highways; • Pavements with greater stiffness offer better fuel economy; • Asphalt must be up to 60 percent thicker than concrete to achieve the same level of stiff ness and fuel economy; • Roughness is also an important factor—there is no statistical difference in roughness between concrete and asphalt pavements in current U.S. national highway system network; • Maintenance is an important factor to reduce impacts with the existing network; • Stiffer pavements in the U.S. could reduce vehicle fuel consumption by as much as 3 percent; • At a decrease of only 1 percent, that would translate into 91 million barrels of crude oil annually ($5.2 billion at today’s oil prices); and • There would be an accompanying decrease of an estimated 15.5 million metric tons of CO2 annually. Buildings • A total of 88 to 98 percent of the CO2e emissions of buildings are due to operating energy requirements (over a 60-year lifetime); and • Total life cycle global warming potential (GWP) of concrete buildings is equal to or lower than alternate designs in steel or wood by 2 to 8 percent over 60 years. Life Cycle Cost Analysis • Historically, concrete prices have been relatively stable and predictable; • Ignoring possible future changes in relative prices can bias planning decisions and lead to significant cost overruns; and • LCCAs without material-specific inflation rates may underestimate the cost of asphalt by as much as 95 percent. Note: Equivalent CO 2 (CO 2e) is the concentration of CO2 that would cause the same level of radiative forcing as a given type and concentration of greenhouse gas. Work at the MIT CSH continues to further refi ne the models that have been developed so far and evaluate new areas of potential impact to maximize the sustainable attributes of concrete. This includes continuing research in the concrete science and LCA/ LCCA arenas. However, given the significant takeaways stemming from the first phases of work, there is now also a great effort to “take to the streets” the research models and findings developed to date—that is, to put these findings into practice and see them applied within concrete companies and by designers and decision makers. Th is being accomplished through a multi-pronged approach that includes roles for industry members and the researchers at MIT as well as other universities. We are validating the MIT models by applying them to real-world data sources and scenarios at the national, state and site-specific levels. MIT is communicating the value of the models and how to use them through research reports, briefs and presentations to a wide spectrum of stakeholders. The national associations have created resources and tools to communicate directly with designers and decision makers and to help industry members do so effectively. Key tenets of the research are also starting to be incorporated into tools and software systems used by designers. How can you get involved? A wide variety of materials have been developed by the MIT CSH and the national organizations. These are available on the MIT CSH website at and through national organizations such as the Ready Mixed Concrete Research and Education Foundation (, the National Ready Mixed Concrete Association ( and the Portland Cement Association ( If you have local contacts within the design and decision-making communities (including architects, engineers, state DOTs and government officials, among others), either for structures or pavements, the national organizations have resources to help you communicate the importance of the MIT CSH models and how to use them. Several state associations and companies have already initiated dialogue, training and application of the models to local data and their experiences can be used as an concrete INFOCUS ı OC1

Table of Contents for the Digital Edition of Concrete inFocus - Spring 2013

Corporate Suite
Enviro Scene
A Legacy in Construction
CalPortland Slip Form Success
Fly Ash FAQ
Acceptance Test Reports for Ready Mixed Concrete
First Batch Plant Certifications in Mongolia
Index of Advertisers
Taking It to the Streets
Impact of Specifications on Concrete Quality

Concrete inFocus - Spring 2013