Water-cement ratio gradients in mortars and corresponding effective elastic properties

Water-cement ratio gradients are modeled through the interfacial transition zone (ITZ) of a mortar with spherical inclusions, The model is a function of the over-all water-cement ratio, volume fraction and radius of sand, specific gravity of cement and thickness of ITZ, Based on experimental data from the literature, the dependence of saturated, homogeneous cement paste is modeled as a function of water-cement ratio. Subsequently, the effective bulk and shear moduli for mortars are determined using a generalized self-consistent method, Finally, application of the model to data in the literature pertaining to elastic wave speeds in saturated mortars composed of 20-30 screened sand with an overall water-cement ratio of 0.3 yielded a mean ITZ thickness of 48.3 mum. (C) 2002 Elsevier Science Ltd. All rights reserved.