Portland cement concrete, which is a fundamental material for the construction industry, faces environmental problems related to significant CO2 footprint. As a result, increasing amounts of wastes and industrial by products are used to replace the Portland cement to create ecological concretes.
Most of these materials have sufficient mechanical strength but often suffer from a lowered durability and esthetical problems. The optimal solution is to produce concrete elements from two types of load bearing concretes. One, ecological having questionable (low) durability and the second designed to be exposed to harsh environmental conditions.