Preparation of high performance foamed concrete from cement, sand and mineral admixtures

Abstract

The titled high performance foamed concrete was developed from Portland cement, ultra fine granulated blast-furnace slag, pulverized fly ash and condensed silica fume by means of pre-foaming process. The resultant foamed concrete presents its thermal conductivity of about 0.16–0.75 W/(m · °C) and 28 d compressive strength of about 1.1–23.7 MPa when its mix proportion varies in the range of cement content 280 kg–650 kg/m³, fly ash 42–97 kg/m³, slag 64–146 kg/m³, silica fume 34–78 kg/m³, and sand 0–920 kg/m³. The compressive strength of the foamed concrete with oven dried bulk density of 1500 kg/m³ in appropriate mix proportion and with small amount of superplasticizer reached as high as 44.1 MPa. Meanwhile, the fresh foamed concrete behaves like an excellent flow-ability, therefore, is especially suitable for the application in case of massive foamed concrete casting in situ and in the case of filling casting into large volume underground irregular voids, except for pre-casting of building components like blocks, bricks, and wall panels.

Keywords

foamed concrete / density / compressive strength / thermal conductivity

References

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