Shrinkage of high-performance fiber-reinforced concrete with adapted rheology

摘要

The results of shrinkage (epsilon(sh)) of fiber-reinforced self-consolidating mortar (FR-SCM), fiber-reinforced superworkable concrete (FR-SWC), and fiber-reinforced self-consolidating concrete (FR-SCC) are compared to results determined from different models. In total, four FR-SCM, five FR-SWC, and 10 FR-SCC, mixtures representing a wide range of mixture proportioning were studied. Five types of fibers, including steel, synthetic, and hybrid fibers having various properties were employed. The fiber volume varied from 0.25% to 0.75% for the FR-SCC mixtures and from 1.4% and 1.6% in the case of FR-SCM mixtures. The epsilon(sh) results were evaluated for 13?months. Test results indicated that the epsilon(sh) of FR-SWC/FR-SCC was lower than that of SCC. The drying shrinkage (epsilon(dr)), which is part of the total shrinkage, epsilon(sh), was found to be mainly affected by the total porosity and volume of pores smaller than 50?nm. The epsilon(sh) results were compared to values predicted from different models, including the AASHTO LFRD (2017), ACI 209 (2008), Bazant B4 (2015), B4s (2015), CEB-FIP (2010), Eurocode 2 (2004), Gardner and Lockman (2000), and JSCE (2007) models that were developed for conventional, non-fibrous concrete. The Aslani and Maia (2013), Khayat and Long (2010), and Poppe and De Schutter (2005) models proposed for self-consolidating concrete and FR-SCC were also considered. The epsilon(sh) models of the fibrous mixtures were modified to better fit the experimental results. The modified epsilon(sh) models were shown to yield accurate prediction of epsilon(sh) of FR-SCM and FR-SWC/FR-SCC. The modified JSCE model provided the best overall prediction for epsilon(sh) for the FR-SCM and FR-SWC/FR-SCC mixtures. (C) 2019 Elsevier Ltd. All rights reserved.