Producing Structural Lighweight Concrete with Artificial Cold Bonded Aggregates and Investigating Its Mechanical Properties

Abstract

In this study, artificial ,prismatic aggregates including %10 fly ash,%50 GGBS(ground granulated blast furnace slag),%40 OPC(ordinary portland cement) and water with NaOH(as an activator) with a mass that is the %37 of the mass of materials counted, were produced by using cold bonding method, and their specific gravity and water absorption rates were investigated. Later, by using these aggregates, structural lightweight concretes including 0,4 water/cement ratio, and silica fume, were designed and 3 series of concrete were produced. First series included 520kg/m3 cement content, and in the other series fly ash and GGBS were replaced in the amount of %42 by mass with the cement. Only In the 3rd series that were different from the other two, strux 90/40 fibres were used and their affect were investigated. Hardened concretes were tested for compressive strength at 7 and 28th days and tested for flexural strength at 28th day. The results showed that its possible to produce a structral lightweight concrete with a specific gravity of 1900-2000 kg/m3 and with a compressive strength of 28-32 Mpa, and GGBS and fly ash with calcium content dont decrease the strength of concrete when they are used as a replacement with cement.