Relationship Between Compressive Strength and Splitting Tensile Strength of Palm Kernel Shell Concrete

Abstract

The use of palm kernel shell (PKS) has gained acceptance in the production of concrete. Compressive strength is the mostly used strength characteristics of concrete. The compressive strength CS of concrete should provide a good basis for predicting the splitting tensile strength STS. The aim of this study is to establish a mathematical relationship between the CS and STS of concrete produced with PKS. In this study, coarse aggregates was fully replaced with PKS at varying water-cement ratios (w/c) for concrete mix ratios 1:1½:3 and 1:2:4. Unit weigth of the PKS, slump, compressive and splitting tesnsile strength were determined. A relationship between CS and STS was developed for the different w/c ratios using exponential function aproximation. Physical property tests carried out on the PKS characterized it as lightweight aggregate with saturated surface dry unit weight of 1.27. The slump revealed that PKS concrete at 0.3 and 0.4 w/c is stiff and not workable. CS and STS at 28day for mix ratio of 1:1½:3 at w/c of 0.3, 0.4, 0.5 and 0.6 were respectively 3.2 and 1.2; 9.4 and 2.1; 10.8 and 2.6; 9.0 and 2.4 N/mm2. The corresponding values obtained for mix ratio 1:2:4 were 3.0 and 1.0, 1.7 and 1.3, 4.5 and 1.6, 7.7 and 1.9N/mm2, respectively. Equations relating CS and STS at 0.3, 0.4, 0.5 and 0.6 w/c were established. It was concluded that PKS concrete produced with mix ratios 1:1½:3 and 1:2:4 performed better in compression and splitting tensile strength at w/c of 0.5 and 0.6.