Influence of the Addition of Palm Kernel Shell and Ash on Concrete Performances: Study of Correlations between Intrinsic Material Properties

Sustainable development objectives in the construction sector is currently hampered by the high cost of materials (cement, aggregates) and the environmental impact of waste in some developing countries. The obtained results in this work on the influence of ash (PKSA) and palm kernel shell (PKS) used as a partial addition of cement and aggregates in concrete composition, enable their valorization as local materials to manufacturing the lightweight concrete with low-cost. This is an interesting contribution to the development of sustainable construction and environmental protection. The used palm kernel shells are produced in the palm oil industry in Republic of Congo. The highest values for density Cd(2348kg/m 3 ), compressive strength Cs(27MPa) and splitting tensile strength Ts(2.4MPa) for concrete using PKSA were obtained at 2.5%. Those for concrete using PKS were obtained at 5 %, i.e. Cd(2165kg/m 3 ), Cs(22MPa) and Ts(1.90MPa). the increase in concrete properties with PKSA compared to PKS is explained by the pozzolanic reaction of the palm kernel ash, which acts as a hydraulic binder. Correlations between fundamental concrete properties reliably describe the influence of PKS and PKSA, with a coefficient of determination R 2 (0.9) superior at 0.5; the obtained mathematical models to prediction the concrete properties are a significant contribution for engineers. PKS is a concrete plasticizer, PKSA is a concrete setting and hardening accelerator. The production of low-carbon concrete with PKSA addition is a major step forward for the concrete industry.