Internal Curing

Internal curing is the process of “curing concrete from the inside out” by using prewetted lightweight aggregates that gradually release water throughout the concrete mix.

This technique, defined by the American Concrete Institute (ACI) as “a process by which the hydration of cement continues because of the availability of internal water that is not part of the mixing water,” helps reduce shrinkage, cracking, and permeability in concrete.

Arcosa Lightweight’s expanded shale and clay aggregates provide an efficient solution for internal curing, resulting in more robust, durable concrete with extended service life.

Key Benefits

Arcosa Lightweight aggregates provide essential internal curing for concrete, reducing shrinkage and cracking, enhancing durability, and supporting long-term structural integrity.

Reduced Shrinkage and Cracking

By gradually releasing water into the concrete mix, Arcosa Lightweight aggregates help keep pores in the cement paste saturated, which mitigates shrinkage and cracking during the early stages of curing. This continuous hydration prevents common issues such as early-age curling, warping, and cracking.

Enhanced Durability and Strength

Internal curing with Arcosa Lightweight aggregates improves hydration throughout the entire concrete structure, reducing permeability and increasing resistance to chloride penetration. The result is a more durable, resilient material that better withstands environmental stresses, including freeze-thaw cycles and exposure to salts.

Compatibility with Supplementary Cementitious Materials (SCMs)

Arcosa aggregates facilitate internal curing that complements the increased water demand of SCMs like fly ash, slag, and silica fume. This makes internal curing particularly advantageous for high-performance and sustainable concrete mixes that incorporate SCMs at higher dosage levels.

Featured Case Studies

U.S. 80 Bridge: A Successful Early Test for ICC Bridge Decks

When the Louisiana Department of Transportation & Development (LADOTD) planned to build a bridge on U.S. 80 over the Kansas City Southern railroad, they chose to incorporate internally cured concrete (ICC) to improve durability and performance. As an early successful test project, this effort demonstrated ICC’s potential to significantly enhance the lifespan of bridge decks.

Internal Curing Gains Ground in Highway Construction: A Durable Solution

Internal curing is being recognized as a significant advancement in concrete technology. Today, the integration of lightweight aggregate (LWA) into concrete offers enhanced performance by reducing cracking, improving durability, and extending the service life of critical infrastructure. From bridge decks to highway pavements, this innovative technique is delivering longer-lasting solutions with lower maintenance costs.

State DOTs See Benefits in Internally Cured Bridge Decks

Faced with the challenge of maintaining aging infrastructure while optimizing taxpayer dollars, state Departments of Transportation are turning to innovations like internally cured concrete to improve bridge deck durability. Worn surfaces not only inconvenience drivers but also lead to frequent, costly repairs. By integrating advanced materials and data-driven decision-making, DOTs are extending the lifespan of critical infrastructure, reducing environmental impact, and improving safety for the public.

Internal Water Reservoirs

Arcosa’s lightweight aggregates act as internal reservoirs, gradually releasing water to support continuous hydration throughout the concrete mix.

Minimizing Shrinkage and Cracking

By keeping the concrete pores saturated, Arcosa aggregates reduce early-age shrinkage and cracking, improving the concrete’s overall durability and lifespan.

Enhanced Density and Durability

Continuous hydration facilitated by internal curing results in a denser, more durable concrete structure, offering increased resistance to chloride ingress and environmental stresses.

Why Choose Arcosa Lightweight for Internal Curing?

Proven Performance: Arcosa Lightweight aggregates are utilized in a variety of high-performance concrete applications, providing enhanced durability and resilience where it’s needed most.
Sustainability Commitment: By reducing maintenance needs and extending the lifespan of concrete structures, Arcosa Lightweight aggregates support sustainable building practices across various industries.
Expert Support: Arcosa offers in-depth technical support for implementing internal curing, ensuring that concrete mixes are optimized for maximum performance.

Ask our Expert: 1-800-342-LITE

Clint Chapman is the Western Region Marketing & Technical Manager for Arcosa Lightweight. Clint is an NRMCA Certified Concrete Technologist – Level 3, with over 20 years’ experience in the concrete industry. The vast majority of which has been in the Lightweight Aggregates industry, with a focus on structural lightweight concrete.

Internal Curing