It’s not too often hot topics “green technology” and “government fiscal responsibility” are necessarily put together in the same sentence regarding infrastructure progress.
Massachusetts Institute of Technology (MIT) formed the Concrete Sustainability Hub (CSH) in 2009 as a research centre for advancing technology transfer from concrete science into the engineering practice by translating the synergy of three fields of study – economic, engineering and architecture – into a hub for concrete sustainability studies relevant to industry and decision makers.
MIT believes the groundbreaking research will set a new standard for life cost analysis (LCA) with its ongoing studies producing the most comprehensive LCA model on record.
According to MIT professor and research team leader John Ochsendorf, “The life-cycle model we are developing will combine the best data on the full range of costs – construction, maintenance, reconstruction, user, direct, and indirect – with a time frame that reflects the real world life of pavements and building materials.”
MIT notes, “The economic study will produce an equally comprehensive life-cycle cost analysis (LCCA) model.” Ochsendorf adds, “Once both studies are completed, MIT will have provided the scientific community, industry leaders and policymakers with a framework to determine the economic and environmental life-cycle costs of selected infrastructure materials throughout the real life of projects.”
In the corporate world, CEMEX is a company heavily involved with MIT’s work and has been conducting their business with a social and environmental message for years.
CEMEX was founded in Mexico in 1906, and they have grown from a small, regional cement firm into a leading global building solutions company with over 50,000 employees worldwide.
CEMEX is an international building materials company that provides high quality products and reliable service to customers and communities throughout the Americas, Europe, Africa, the Middle East, and Asia.
Their operations network produces, distributes, and markets cement, ready-mix concrete, aggregates, and related building materials in more than 50 countries. CEMEX maintains trade relationships with more than 100 nations.
Thinking and working green, CEMEX’s USA Houston based Frank Craddock, Executive Vice President, Commercial, offers: “Most LCA models make the mistake of only looking at the construction phase. There is a need to look at the operating phase of a working building and pavement. A cradle-to-grave analysis needs to be performed to know overall energy use, economic and environmental cost of a project. The life cycle analysis should also consider cost at the end life of the project and prospects for material recycling. When a building or road is to be demolished, can the material be recycled?”
CEMEX’s commitment to energy efficiency in their innovative practices, technology, and operating facilities with respect for communities was rewarded in 2010 with receipt of top environmental awards.
Energy start partner of the year, Wildlife Habitat Council (WHC) recognised CEMEX USA with two of the Council’s top national awards, including the William W. Howard C.E.O. Award for environmental stewardship achieved through educational initiatives by CEMEX’s Aggregate Division, in Florida.
This is the WHC’s highest award, as it recognises a company which has a history of striving for excellence in Conservation, Education, and Outreach (C.E.O.). Along with receiving the C.E.O. Award, the CEMEX centre Hill Quarry, was awarded the Corporate Lands for Learning (CLL) of the Year Award, which is designed to recognise a site for outstanding environmental education, stewardship and voluntary employee efforts.
Frank Craddock, along with fellow Houston based CEMEX USA colleague Francisco Uzcategui, Vice President Commercial Strategy & Marketing, answered questions on how all this works when academic scientific study plays out in the business and government realities.
BKH: Please give a short description of the MIT HUB group exactly.
CEMEX: The Concrete Sustainability Hub is a centre for advancing technology transfer from concrete science into the engineering practice by translating the synergy of three fields of study – economic, engineering and architecture – into a hub for concrete sustainability studies relevant to industry and decision makers. The Hub was created in 2009 with the participation of MIT’s schools of Engineering, Architecture, and Business along with the support of the concrete industry.
BKH: In layman’s terms, what are “life-cycle analysis” and the measurements?
CEMEX: It is the process by which you evaluate a project from conception, to construction, to the use phase finalising with the demolition phase. An environmental life cycle analysis is referred to as LCA and an economic life cycle cost analysis is referred to as LCCA.
In many instances the use phase of an asset is responsible for most of its life cycle impact. It is imperative to run a comprehensive analysis that incorporates all elements of a project’s life cycle. The inputs used in the analysis must be correct or the output of the analysis can be misleading.
BKH: Explain why concrete may be greener in construction, commercial performance, and more fuel efficient for both roads and the vehicles driving on concrete roads.
CEMEX: Concrete roads are more sustainable when it comes to construction because of its durability. These roads last longer than comparable materials with limited to no maintenance. This translates into significant CO2 emissions savings.
It is widely known that over 90% of CO2 emissions come from the use phase of a road. Research in Canada and Japan has shown that vehicles travelling over concrete pavements have higher fuel efficiency of 1-4% when compared to those riding over asphalt. MIT will be conducting studies to determine fuel efficiency differences of raiding over different pavement materials.
Finally, concrete can be recycled at the end of the life of a road. But this is a rare scenario, as most concrete roads are still in use long after their projected service life.
When we consider single family residential buildings, MIT has reported that the use phase represents 90% of CO2 emissions over the life of the asset. The advantages of higher R-value and lower thermal bridging enable concrete wall systems to deliver energy savings in heating, cooling, and ventilation that can represent 20% in energy savings and CO2 emissions compared to conventional construction.
BKH: Are current new building material and construction method advanced technologies cost effective?
CEMEX: National long term pavement performance data shows that concrete pavements have historically been over designed and have carried up to 10 times more loads than for which they were designed. While this over performance is good; it comes at an initial construction cost, which agencies have historically not been willing to accept despite lower usage cost.
A recently developed design procedure, called the Mechanistic-Empirical Pavement Design Guide (MEPDG) removes this over design and lowers the cost of concrete pavements significantly, 10-20% or more.
In addition to the improvements in predictive modelling and comprehensive analysis of actual performance data, innovations in design features, material and mix designs, the use of supplementary cementing materials such as fly ash and other waste by-products, and construction techniques are making concrete pavements more durable, more environmentally sustainable, and extending their life well beyond their historical performance.
Concrete wall systems in residential construction can be 30–40% more expensive than conventional wall systems construction representing 2-3 % incremental construction cost. However, energy savings of 20% more than compensate the carrying cost of the additional initial investment.
For a significant change to take place, incentives need to be realigned. If potential home buyers were aware of the energy and other benefits of concrete wall systems, builder would respond by making the additional investment and home owner would reap the benefits over the life of the asset. Governmental bodies could also support more sustainable building practices through building code changes or appropriate incentives for energy efficient investments.
BKH: Are these newest technologies being bid for newest projects now?
CEMEX: Missouri DOT (MODOT) has fully adopted the MEPDG and is using it routinely on all their pavement designs. The Indiana DOT (INDOT) has used it on over 100 projects since December 2009. INDOT senior management also has performed a cost evaluation to quantify savings. On the 23 projects they reviewed, they estimate that Indiana has saved over $10M versus designs previously used.
MODOT has combined the use of MEPDG with another innovation called Alternate Design / Alternate Bid (ADAB). ADAB is a process in which both concrete and asphalt pavement designs are developed for the project and the contractor then chooses which material to submit for his bid. The bid that wins the project is the bid and pavement type that has the lowest life cycle costs.
The idea of ADAB is to increases competition and lower cost by bringing additional contractors to the bidding table. According the MODOT, the use of ADAB has lowered costs between 4.8-8.6%. MODOT estimates that the use of MEPDG and ADAB has saved the state approximately $1.6B as of the last reported data in July 2009. (MODOT Alternate Pavement Approach, Dave Ahlvers, Presentation to the 2009 AASHTO Subcommittee on Construction.)
Of the 124 Alternate Projects thru July 2009, concrete has won 83, and asphalt has won 41 of the projects. In all but 3 cases, the winner has been based solely on initial costs.
Many other state DOTS are using it experimentally alongside their current design procedures for comparison purposes. Overall, 80% of the states have plans to implement the MEPDG within the next 5 years.
BKH: What do you see for the future in building materials technology advancement type and benefit?
CEMEX: There are many trends in today’s market. There are two initiatives our industry is actively working on. First is to develop solutions that provide a higher efficiency in use phase by leveraging the attributes of products, such as creative design alternatives like using concrete’s thermal mass to reduce heat loss in water pipes.
Second is to significantly reduce production emissions through the use of nanotechnology. MIT scientists at the Concrete Sustainability Hub, have developed the first atomistic-scale computational model of concrete from which they are expected to predict new structures and improved properties that will reduce CO2 emissions in concrete.
BKH: Thank you gentlemen.
In reality, the combination of academic research study and business implementation will allow productive political compromise at its best. It satisfies the left looking for green accountability and the right looking for fiscal accountability. That’s a legitimate breakthrough everyone can embrace.
Note: Also see Part 2 Fiscal Responsibility