Use of animal proteins as foaming agent in cementitious concrete composites manufactured with recycled PET aggregates

Manufacturing of lightweight building materials is identified as an alternative procedure for valorising reused materials. With intent to valorise two wastes of food industry at the same time, this paper describes an innovative use of animal protein as foaming agent while consumed plastic bottle wastes are introduced as light aggregates. Relative changes in properties of concrete composites due to introducing proteins are experimentally investigated here. The results presented show that the two wastes clearly improve the flowability of the mortar. Both mechanical properties and bulk density of the composites are affected too, but thermal conductivity is improved. In this way, the obtained composites would appear to be low-cost materials which would contribute to resolving some of the solid waste problems in addition to conserving energy. (C) 2009 Elsevier Ltd. All rights reserved.