Relationship between Density and Strength for High-volume Fly Ash Lightweight Porcelanite Concrete

Abstract

In concrete construction, there are many advantage in reducing total load on the structure. One of the methods to reduce the load is using lightweight concrete, LWC. The concrete production is not sustainable due to its consuming a lot of Portland cement, which is responsible for the emission of greenhouse gases that cause global warming. One of the effective methods to reduce the impact of negative environmental concrete industry is using by product materials such as fly ash as a partial replacement by weight of cement. In the present study, the ability of producing high-volume fly ash structural lightweight aggregate concrete was verified. This concrete was produced by using Porcelanite aggregate and a large amount of type F fly ash as partial replacement by weight of cement, 50, 60 and 70 %. The studied characteristics are: density, water absorption, compressive and splitting tensile strengths at different ages. Lightweight concretes containing high-volume fly ash, 50 and 60 % by weight of cement, have proven themselves as structural lightweight concrete with compressive strength fc, more than 17 MPa at 28 days age. The results in this study showed that increasing fly ash content up to 70 % will decrease the compressive strength but on the other hand it will significantly reduce density and increasing water absorption.