The effect of expansive agent and cooling rate in the performance of expanded glass lightweight aggregate as an internal curing agent
Revista : Construction and Building MaterialsVolumen : 121505
Tipo de publicación : ISI Ir a publicación
Abstract
Lightweight aggregates can provide internal curing (IC) in concrete and reduce autogenous shrinkage and related cracking, but they produce a reduction in concrete strength. Expanded glass lightweight aggre-gates (EG-LWAs) allow for design and engineer their properties to develop better IC agents. Expansive agent silicon carbide (SiC) content and post-expansion cooling rates were systematically varied in order to develop a competitive IC agent with a controlled reduction in concrete strength. Slow cooling produced the EG-LWA with the highest intrinsic strength, but with limited water delivery capacity. Rapid cooling produced EG-LWA with lower intrinsic strength, but with the highest water delivery capacity; they reduced autogenous shrinkage at 28 days by 34% and 50% for specimens with 2.5% and 5.5% of SiC,respectively. The results of this research indicated the possibility to maximize the capacity of EG-LWA as IC agent through an optimum SiC dosage and cooling treatment.