Mineral additions as pigments and mechanical property enhancers in self-compacting natural hydraulic lime concrete

Abstract

This article investigates the incorporation of mineral-based pigments to enhance both the aesthetic and mechanical properties of self-compacting concrete made with natural hydraulic lime. The research focuses on three specific pigments—local red silt clay, ochre, and blue pigment—selected for their distinct colors and potential pozzolanic reactivity. Rigorous experimental analyses were conducted to assess the compatibility of these pigments within natural hydraulic lime-based concrete systems, with emphasis on their effects on rheological behavior, color stability, and mechanical performance. The results show that all pigments produced satisfactory color outcomes, highlighting variations in color depth and brightness. Moreover, the addition of these pigments positively impacted the mechanical properties of the concrete, improving both compressive and flexural strengths in specific cases. The study demonstrates that pigmented self-compacting natural hydraulic lime concrete offers visually appealing solutions for both architectural and engineering applications, while also providing environmental benefits by reducing CO2 emissions compared to traditional Portland cement-based concretes. This innovative approach supports sustainable construction practices by utilizing locally sourced natural pigments to enhance the aesthetic and structural properties of self-compacting natural hydraulic lime concrete.