Investigation on the Effect of Shrinkage Reducing Admixtures on Shrinkage and Durability of High-Performance Concrete

Abstract

Abstract Because of the advances in material science, new materials are launched to market that make it possible to produce concretes with more desirable properties for technical applications. These new concretes that cannot be made using the common materials and mixing ratios are called high-performance concretes. High-performance concretes are usually made with a low water-to-cement (w/c) ratio and high cement contents. High-performance concrete and its properties have gained the attention of engineers in recent years. One of the major shortcomings of cement-based materials such as concrete is their shrinkage. In this study, the effect of shrinkage-reducing admixture (SRA) on the shrinkage and durability of concrete is investigated. To examine SRA effects on shrinkage, free and constrained shrinkage tests are carried out while taking into account the impact of changing w/c ratio and cement content. Moreover, to study the durability of high-performance concrete, tests are carried out on durability parameters, including electrical resistance, depth of water penetration under pressure, and the percentage of water absorbed by the concrete. The results show that the use of shrinkage-reducing material decreases free shrinkage of concrete. When applying a lower w/c ratio and higher contents of cementitious materials, the use of this substance has a greater impact. Constrained shrinkage test results also indicate that the use of SRA additive causes a significant increase in the time of shrinkage crack formation during the test. The results of the durability tests indicate significantly improved durability properties of concrete aged 28 days.