Aslani et al. / J Zhejiang Univ-Sci A (Appl Phys & Eng) 2012 13(6):407-419 407 Shrinkage behavior of self-compacting concrete Farhad ASLANI † , Shami NEJADI (Centre for Built Infrastructure Research, School of Civil and Environmental Engineering, University of Technology Sydney, Australia) † E-mail: Farhad.Aslani@uts.edu.au Received Dec. 13, 2011; Revision accepted Mar. 19, 2012; Crosschecked Apr. 16, 2012 Abstract: In the structures where long-term behavior should be monitored and controlled, creep and shrinkage effects have to be included precisely in the analysis and design procedures. Shrinkage varies with the constituent and mixture proportions, and depends on the curing conditions and the work environment as well. Self-compacting concrete (SCC) contains combinations of various components, such as aggregate, cement, superplasticizer, water-reducing agent and other ingredients which affect the properties of the SCC including shrinkage. Hence, the realistic prediction shrinkage strains of SCC are an important requirement of the design process for this type of concrete structures. This study reviews the accuracy of the conventional concrete (CC) shrinkage prediction models proposed by the international codes of practice, including CEB-FIP (1990), ACI 209R (1997), Eurocode 2 (2001), JSCE (2002), AASHTO (2004; 2007) and AS 3600 (2009). Also, SCC shrinkage prediction models proposed by Poppe and De Schutter (2005), Larson (2007), Cordoba (2007) and Khayat and Long (2010) are reviewed. Further, a new shrinkage prediction model based on the comprehensive analysis on both of the available models, i.e., the CC and the SCC is proposed. The predicted shrinkage strains are compared with the actual measured shrinkage strains in 165 mixtures of SCC and 21 mixtures of CC. Key words: Self-compacting concrete (SCC), Conventional concrete (CC), Shrinkage, Long-term behavior, Concrete structures doi:10.1631/jzus.A1100340 Document code: A CLC number: TU37 1 Introduction Basically, the self-compacting concrete (SCC) consists of the same components as conventional concrete (CC) (cement, water, aggregates, admix- tures, and mineral additions), but the final composi- tion of the mixture and its fresh characteristics are different. In comparison with the CC, the SCC con- tains larger quantities of mineral fillers such as finely crushed limestone or fly ash, higher quantities of high-range water-reducing admixtures, and smaller maximum size of the coarse aggregate (Aslani and Nejadi, 2011a; 2012). These modifications in the composition of the mixture affect the behavior of the concrete in its hardened state, including the creep and the shrinkage deformations. The overall shrinkage of concrete corresponds to a combination of several shrinkages, that is, plastic shrinkage, autogenous shrinkage, drying shrinkage, thermal shrinkage, and carbonation (chemical) shrinkage. In designing the CC, shrinkage is taken as drying shrinkage, which is the strain associated with the loss of moisture from the concrete under drying conditions. The CC with a relatively high water cementitious material ratio (w/c) (higher than 0.40) exhibits a relatively low autoge- nous shrinkage, with values less than 100 μstrain (Davis, 1940). In contrast, the SCC used in precast, prestressed applications has typically a low w/c ratio (0.32 to 0.40). Lower w/c values, coupled with a high content of binder, lead to greater autogenous shrinkage. Such shrinkage increases with the use of finely ground supplementary cementitious materials and fillers employed in the SCC. Therefore, both drying and autogenous shrinkage deformations have to be accounted for in the structural detailing of the Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering) ISSN 1673-565X (Print); ISSN 1862-1775 (Online) www.zju.edu.cn/jzus; www.springerlink.com E-mail: jzus@zju.edu.cn © Zhejiang University and Springer-Verlag Berlin Heidelberg 2012