Properties of silt-based foamed concrete: A type of material for use in backfill behind an abutment

This paper addresses the influence of the silt content and concrete density on the physical and mechanical properties of foamed concrete, including the compressive and flexural strength, water absorption, pore structure, and hydration products. The results of the experimental tests show that the compressive and flexural strength of the foamed concrete increase with the increasing density and decrease with the increasing silt content. The early strength of foamed concrete containing 20% silt is 32.5% higher than that of foamed concrete without silt, regardless of the density. The water content has little impact on the compressive strength of foamed concrete-containing silt. The foamed concrete continues to hydrate when immersed in water. The average pore diameter of foamed concrete with silt decreases with the increasing density and increases with the increasing silt content. The X-ray diffraction (XRD) results show that the hydration products of the foamed concrete mixed with silt are similar to those of ordinary concrete, and no other unknown product is formed. (C) 2020 Elsevier Ltd. All rights reserved.