Speed Up the Concrete Process With Early Strength

Concrete needs time to harden as the hydration reactions form the strong bonds that make up its strength. It takes 28 days or more for the compressive strength of conventional concrete to reach its peak. This long wait can be frustrating to construction crews and clients alike when fast-track projects are underway.

One way to speed up the process is by using high early strength concrete, which reaches its peak in just 24 hours after pouring. This allows pavement repairs, full-depth patching, and new construction to be completed and opened for traffic sooner than with conventional mixes.

High early strength concrete is made with a special type of portland cement that reacts faster than regular concrete, and it is used with lower water-to-cement ratios. It can achieve a structural concrete quality of about 2,500 psi within two to three hours after placing, which is sufficient for pedestrian traffic or even support of light vehicles. This can improve construction turnaround times and minimize labor costs and overhead.

The type of cement used to produce high early strength is typically known as Type III Portland cement, and it can be produced by blending the cement with ground granulated blast furnace slag or with an accelerating admixture like calcium chloride. Increasing the water to cement ratio and using chemical admixtures and supplementary cementitious materials can also improve the early strength of concrete. The use of autoclave curing can help as well by retaining the heat of hydration and reducing the time required for a project to attain its final strength.