Long-term behaviour of concrete incorporating a shrinkage-reducing admixture

Chemical admixtures have had a fundamental role in the application of higher quality concretes that fulfill the increasing requirements of mechanical and durability properties with improved rheology. Some chemical admixtures such as shrinkage-reducing admixtures (SRA) also permit the mitigation of certain undesirable aspects of the behaviour of concrete such as shrinkage and creep which is of significant importance in structural design. The paper deals with the evaluation of the shrinkage and creep behaviour of concretes incorporating a commercially-available glycol-based SRA. The results obtained over a period of six months indicate a remarkable reduction in the total shrinkage strain and creep coefficient under drying conditions, when compared with reference concretes without SRA. However, there is a negative effect of the SRA on the compressive strength values which are slightly lower than those of the reference concretes.