Green Concrete Performance One-Day Workshop

The National Institute of Standards and Technology will conduct a one-day workshop to support the expanded use of industrial by-product materials throughout the concrete construction industry.

The goal of the workshop is to identify and prioritize the measurement science needs for quantifying and assuring the short- and long-term performance of concretes having up to 50 % of the portland cement replaced with industrial by-product (IBP) materials. The workshop will solicit input from the construction industry and various public sector agencies (e.g., FHWA, state DOTs).

The outcome of the workshop will be a 5-year roadmap outlining the R&D, measurement science, and services needs of both the private and public sectors to improve the design, construction, and long-term performance of concretes containing up to 50 % IBP materials (e.g., fly ash, slag, crushed waste glass, rice husk ash); these blended systems are referred to here as Green Concrete. This roadmap also will provide a framework for the development of new standards and codes for the performance of Green Concrete. NIST will use this roadmap to help guide its program and to ensure that measurement science keeps pace with and catalyzes technological innovation in the field of construction materials.

Background: Cement-based materials are the most abundant manufactured materials in the world. These materials, however, have a large embodied energy content, and are associated with large volumes of green house gas (GHG) emissions. Using supplementary industrial by-product (IBP) materials is the most viable means of reducing the embodied energy, and the associated GHG emissions. In addition, the expanded use of IBP materials also helps to make these materials much more cost competitive. Unfortunately, as the portland cement replacement ratio increases, the uncertainties in performance, both at the time of construction and over the long-term, also increase. Therefore, to increase the industry average cement replacement by IBP materials, there is a strong need for better standards, guides, and tools for designing, constructing, and assuring the long-term performance of these materials. With improvements in standards and guides, these materials can perform reliably during construction and throughout their service life.

The measurement science barriers to the expanded use of IBP materials in concrete arise from a number of technical needs:

• New mix design guides and tools that address binary and ternary mixtures;
• Tests to assure performance during construction to support new specifications;
• Improved guidelines and tools optimizing early-age performance;
• Evaluation and assessment of current measurement techniques for characterizing and quantifying performance;
• Performance standards, measurement methods, and predictive tools.

The one-day workshop will be divided between keynote talks and breakout discussion sessions. At the workshop, you will be asked to provide input on the following topics as they relate to the measurement science need for assuring the performance of Green Concrete in ways that will expand the use of IBP materials:

• Challenges in developing new blended mixtures;
• Predicting the influence that by-product materials have on early-age properties;
• Modifying mixtures to adjust for new batches of materials;
• Relating changes in performance to changes in the environment;
• Rapid field tests for monitoring/predicting performance;
• Long-term durability issues for Green Concretes;

Your participation is critical to ensure that the roadmap is comprehensive and reflects the diverse needs of the stakeholders involved with ensuring the expanded use of supplemental materials in concrete.