Influence of Neem Seed Husk Ash (NSHA) on the Strength of Laterized Concrete

Abstract

The processing of neem products from the neem tree generates a considerable amount of waste each year. The purpose of this study is to evaluate the properties of laterised concrete containing neem seed husk ash (NSHA) as an admixture. The neem seed husk was obtained from a neem oil processing company in Katsina – Nigeria, dried and burned in the open air before being calcined in an oven at 650°C to make an ash. X-ray Fluorescence (XRF) was used to analyze the chemical composition of neem seed husk ash. Grade 25 concrete was made with 0, 10, 20, 30, and 40 % by weight of fine aggregate substitution with sand. The NSHA was then added to the concrete at a ratio of 2, 4, 6, 8, and 10 % using optimal laterite content of 20 %. Workability tests were carried out for each percentage replacement of fine aggregate with laterite and percentage addition of NSHA to laterised concrete at a laterite content of 20%. At ages of 7, 14, 28, and 56 days, 100 mm x 200 mm cylinders were tested for compressive strength and splitting tensile strength. With increasing laterite and NSHA content, the slump, compressive strength and tensile strength of the concrete decrease. At 20 % laterite content and 4 % NSHA addition, the compressive and tensile strengths were 28.38 N/mm² – 29.10 N/mm² and 2.13 N/mm² – 2.23 N/mm² respectively. Therefore, laterised concrete with NSHA as an admixture can be produced by replacing fine aggregate with laterite at an optimum laterite content of 20 % and addition of NSHA at a maximum of 4 %.