56-day Strength for Sustainability
By using a 56-day compressive strength for concrete instead of the standard 28-day strength, the cement content in concrete can be reduced. The concrete will obtain the same ultimate strength needed and since less cement is used, the carbon footprint of the concrete is reduced. In addition to using a 56-day compressive strength, a partial replacement of cement by additives can improve the performance of concrete in strength and durability. The use of this alternative method can depend on project requirements. For example, high strength, high rise construction more frequently uses compressive strengths based on 56 -day compression tests.