Proposal for Ordinary Concrete Formulation from Different Cements of Strength Class 42.5R for the Informal Construction Sector

Abstract

Faced with the recurring collapses of residential buildings affecting the civil engineering sector in Côte d’Ivoire, this study aims to evaluate and compare the performance of 42.5R strength class cement produced by four local cement plants (BEL, CIM, CUR and GUE) within the framework of a standardized, ordinary concrete mix design (class C20/25 to C30/35). The experimental protocol consisted of the determination of the physical properties (water porosity, water absorption and dry density) and mechanical properties (splitting tensile tests, 3-point bending tensile tests and compressive strength) carried out on concrete specimens at 7, 14 and 28 days. The results show that the concretes formulated with the different cements meet the mechanical strength criteria of ordinary concretes. A comparative analysis of the results highlighted distinct performance characteristics: concrete formulated with GUE cement provided the best mechanical strength at all ages, followed by concrete made with BEL cement, which stood out for its high long-term performance. Concrete made with CIM and CUR cements also demonstrated satisfactory results, confirming their compliance with the required standards. These performance variations are attributed to differences in mineralogical composition and grind fineness of the different cements. These formulations can provide a reliable source for concrete manufacturers in the informal construction sector. This study demonstrated that local 42.5R strength class cements can indeed be used for the formulation of ordinary concrete, providing a viable and standard-compliant solution for improving the quality and durability of construction.