Eco-friendly Portland cement with low clinker, using brick waste or granite waste powder

The aim of this work was to produce a new type of limestone-based Portland cement (LPC) by minimising the amount of clinker (in the range 50–64%) in accordance with the European standard EN 197-5. Such cements are called CEM II/C-M. The new LPC produced, which meets the specific requirements of EN 197-1, was prepared by partially replacing clinker with 5–20% granite waste powder or brick waste powder (BWP) and adding a constant percentage of 20% limestone filler and 6% gypsum. The new LPC powder was evaluated for chemical characterisation, specific surface area and density. The consistency, setting times and soundness properties of the LPC paste were investigated. In addition, the compressive and flexural strengths, drying shrinkage and chemical resistance (hydrochloric acid and sulfuric acid) of mortars prepared with the new LPC were studied. The LPC materials produced with 5% or 10% BWP showed improved mechanical properties, drying shrinkage and durability compared with the reference systems. This study contributes to the development of new cements by minimising the clinker content. The new LPC prepared by substituting clinker with up to 10% BWP can be classified as 32.5R cement.