Floating concrete! Light-weight concrete from granulated cork waste

The mechanical properties of concretes are affected by a wide range of variables. At the mixing stage these include: cement/aggregate ratio; aggregate size and density; and water/cement ratio. In terms of mechanical performance, an optimum mix is normally one in which there are no free air gaps. Minimising the number of air gaps, or void volume. can be achieved by careful choice of the three variables given above. In addition, mixing aggregates of different sizes can also reduce void volume. In the absence of any standard method for designing concrete mix for materials like cork, which has a very high angularity and 'apparent water absorption' values, two approaches were adopted. One was based upon Fuller's curve (MIX1) and another was based on the 'minimum air void' volume approach (MIX2). These mixes were obtained by using cork granules of large, medium and small size. Composites with the density range of 246 to 854 kg/m(3) were made following MIX1 and 564 to 830 kg/m(3) with MIX2. Data is provided on the effects these mixes have on: composite moisture content; compression strength; energy absorption efficiency; flexural strength and load/deflection behaviour.