Determining the water absorption of recycled aggregates utilizing hydrostatic weighing approach

The water absorption of aggregates is a key parameter in concrete mix design. As the adhered mortar of recycled aggregates present a long time of saturation (>24 h). A new approach of water absorption measurement was developed using hydrostatic weighing in order to observe the kinetic absorption of aggregates, and to obtain a necessary water quantity added in different steps in concrete mix. Experimental results indicate that the model of capillarity processes of aggregates can be obtained using Hall's model. A good correlation was obtained between the current method NF EN 1097-6 and hydrostatic weighing approach. A necessary time for the total saturation of recycled aggregates was evaluated. (C) 2011 Elsevier Ltd. All rights reserved.