Replacement of scoria with wastage of ambo sandstone for the production of hollow concrete blocks

Abstract

One of the most important ingredients of hollow concrete block (HCB) is aggregate that differ depending on their classification. The most common aggregate used for HCB are pumice and scoria. As many researchers conducted the concrete produced from both aggregate are light weight and also the aggregate in hollow concrete blocks are partially or totally replaced with different types of materials and wastage of some product to reduce the environmental pollution. The main objective of this study was to investigate the relevance of hollow concrete block produced as replacement of scoria with wastage of Ambo sandstone. Specifically it focused in determining the physical properties of wastage of Ambo sandstone aggregates and scoria, determine compressive strength of hollow concrete blocks produced at each replacement and to compare the production cost. In addition workability, unit weight and water absorption of hollow concrete were conducted. This experimental study was conducted by preparing of hollow concrete blocks test sample and 108 HCB sample was produced. The test sample of hollow concrete blocks was produced by using mix proportion 1:4:2 of cement, scoria and 01 crushed aggregate. Out of the four parts of scoria aggregate, scoria was replaced with 20, 40, 60, 80 and 100% amount of wastage of Ambo sandstone by volume. According to this study, the hollow concrete block with 100% scoria achieved 3.85Mpa mean compressive strength and the hollow concrete block with 100% wastage of Ambo sandstone achieved 6.83Mpa mean compressive strength. The production cost of all hollow concrete blocks with wastage of Ambo sandstone was lower than hollow concrete block without wastage of Ambo sandstone. According to the water absorption comparison made the hollow concrete block with wastage of Ambo sandstone was found lesser absorptive and heavier than without wastage of Ambo sandstone. Hollow concrete block with wastage of Ambo sandstone in this study has achieved better cost reduction in production cost, smaller increase in weight, reduction in water absorption and high increase in compressive strength than hollow concrete blocks without wastage of Ambo sandstone. The study further recommended to the construction industry in Ambo and around Ambo town to use wastage of Ambo sandstone for production hollow concrete blocks instead of other aggregate.