Title:
Shrinkage of Precast, Prestressed Self-Consolidating Concrete
Author(s):
Kamal H. Khayat and Wu Jian Long
Publication:
Materials Journal
Volume:
107
Issue:
3
Appears on pages(s):
231-238
Keywords:
autogenous shrinkage; drying shrinkage; prestressed concrete; self-consolidating concrete; shrinkage models
DOI:
10.14359/51663751
Date:
5/1/2010
Abstract:
The proper evaluation of shrinkage is critical for the design of prestressed structural members. An experimental program was undertaken to evaluate autogenous and drying shrinkage of precast, prestressed self-consolidating concrete (SCC). Sixteen SCCs with a slump flow of 680 ± 20 mm (26.7 ± 0.8 in.) were evaluated. These mixtures were made with 440 to 500 kg/m3 (742 to 843 lb/yd3) of binder, Type MS cement or HE cement; and 20% Class F fly ash; 0.34 to 0.40 water-cementitious material ratio (w/cm); viscositymodifying admixture content of 0 to 100 mL/100 kg (0 to 1.53 fl oz/cwt) of binder, and 0.46 to 0.54 sand-to-total aggregate volume ratio. Two high-performance concretes (HPCs) with 0.34 and 0.38 w/cm and slump of 150 mm (5.9 in.) were also investigated. The SCC developed 5 to 30% higher drying shrinkage at 300 days than the HPC but with similar autogenous shrinkage. The shrinkage was compared to prediction models proposed by AASHTO 2004 and 2007, CEB-FIP 90, GL 2000, and ACI 209R. The CEB-FIP 90 and a modified AASHTO 2004 model was found to provide an adequate prediction of shrinkage for precast, prestressed SCC.