Strength, Durability, and Microstructure of Foamed Concrete Prepared Using Special Soil and Slag

Abstract

Foamed concrete (FC) is a lightweight building material widely used in thermal insulation walls, backfill, and other fields. Generally, foamed concrete is prepared using cement, which consumes a lot energy and resources. In this study, three kinds of special soil (SS) and slag powder (SP) were used to prepare foamed concrete. The content of SS was 25%, and the content of SP was 35%, 45%, and 55%. The mechanical properties, durability properties, and microstructure of special soil-slag foamed concrete (SSFC) were studied. With the increase in SP content, the water absorption and drying shrinkage of SSFC increased and the compressive strength of SSFC decreased. The water stability coefficients of SSFC were all higher than 0.7, which met the requirements of engineering applications. The porosity and the average diameter of pores of SSFC increased with the increase in SP content. The porosity of SSFC was less than 46% when the replacement percentage of SP was less than 35%. The successful application of SS and SP in foamed concrete provides an effective approach to waste utilization.