What is Enhancing Performance with Internally Cured Concrete (EPIC2)?
Internal curing increases concrete’s resistance to early cracking, allowing the production of higher-performance concretes that may last more than 75 years. Shrinkage cracking in concrete is a key limiting factor in achieving acceptable long-term performance in concrete bridges, roads, and repairs. When this cracking occurs at an early age, it leaves the concrete and embedded reinforcement exposed to degradation, reducing the service life of the structure. Unlike conventional curing where water is supplied on the concrete's surface, internal curing provides a source of moisture from inside the concrete mixture, improving its resistance to cracking and overall durability.
Improved Infrastructure That Lasts Longer
Internal curing is primarily used in concrete bridge decks where a reduction in shrinkage coupled with lower-permeability mixture designs can provide substantially improved protection to the steel reinforcement. In paving and overlays, the technology reduces the magnitude of crack widths and curling deformations and can be used to extend the spacing between engineered joints. For patching and repair materials, internal curing minimizes the potential for restrained shrinkage cracking associated with high cement content mixtures designed to develop strength rapidly.
BENEFITS
Versatility. Internal curing can be used anywhere traditional concrete is used. It follows the norms of industrial concrete production, making it accessible to any producer already familiar with the state of practice.
Durability. Internal curing mitigates shrinkage cracking that is particularly problematic in low water-to-cementitious materials ratio concretes, allowing construction with lower permeability concretes to improve durability.
Cost Savings. Higher-durability concrete mixtures can last several times longer than traditional concretes, reducing the need to rehabilitate or replace critical elements such as bridge decks during the design life of the bridge, resulting in life-cycle cost savings.
Embodied Carbon Reduction. Internally cured concrete mixtures can be designed with lower water-to-cementitious materials ratios and increased utilization of natural, waste, or alternative recycled cementitious products without reduced performance or increased risk of cracking.
Learn more about this EDC-7 Innovation.
Enhancing Performance with Internally Cured Concrete (EPIC2)
Stage of Innovation:
DEVELOPMENT
(April 2023)
NJDOT has not used internally cured concrete on any projects. The department has a lightweight aggregate specification that can be used for internally cured concrete mixes at this time, but no mix design has been approved. Departmental SMEs are actively participating in webinars and peer exchanges related to this innovation. The programmatic areas have been researching and reviewing literature and conducting a literature review on the material, its uses, limitations, et cetera. EPIC is the subject of a research project, sponsored by the NJDOT Bureau of Research, which is about to begin with an estimated completion date in 2025. In addition, the department already has testing capabilities in place for such materials.
What’s Next?
Several steps are planned for advancement of this initiative in New Jersey.
Steps to gather more information and best practice include reaching out to New York State Department of Transportation and other DOTs for their experiences with the material and lessons learned, researching NJDOT projects that have used lightweight aggregates, gathering feedback from industry including contractors and suppliers; and coordinating with NJDOT’s Bureau of Research on the research project on internally cured concrete.
Steps internal to NJDOT include: identifying and evaluating potential test bridge projects and coordinating with Bridge SMEs for application; identifying approved suppliers who are willing to complete this type of work; submitting an internally cured concrete mix design for approval; developing and drafting a special provision for the use of internally cured concrete; and performing research studies and laboratory trials on approved mix designs.
Enhancing Performance with Internally Cured Concrete (EPIC2): NEW AND NOTEWORTHY
