Early strength enhancement for sustainability in the precast concrete industry

Promoting sustainability is becoming nowadays a major issue for the precast concrete industry. The challenging target may be achieved mainly by reducing the consumption of energy for concrete curing and by optimizing the mix composition. This can be done including significant amounts of Supplementary Cementitious Materials, using cements with lower clinker content or decreasing the cement content that, very often, is used only to achieve the required early strength. At the same time, high productivity and turnaround of molds is recognized as a critical economical factor in the precast production and can be obtained only if strength development is fast enough to allow safe demolding. Proper acceleration of the early hydration of cement could allow a cost effective and sustainable concrete production, thus combining the somehow conflicting needs mentioned above. A new accelerator, based on finely dispersed hydrated cement particles, is presented here, which fulfils the current expectations of the precast concrete industry.