Self-consolidating concrete (SCC) is a new, innovative construction material that
can be placed into forms without the need for mechanical vibration. The mixture
proportions are critical for producing quality SCC and require an optimized combination
of coarse and fine aggregates, cement, water, and chemical and mineral admixtures. The
required mixture constituents and proportions may affect the mechanical properties,
bond characteristics, and long-term behavior, and SCC may not provide the same inservice
performance as conventional concrete (CC). Different SCC mixture constituents
and proportions were evaluated for mechanical properties, shear characteristics, bond
characteristics, creep, and durability. Variables evaluated included mixture type (CC or
SCC), coarse aggregate type (river gravel or limestone), and coarse aggregate volume.
To correlate these results with full-scale samples and investigate structural behavior
related to strand bond properties, four girder-deck systems, 40 ft (12 m) long, with CC
and SCC pretensioned girders were fabricated and tested.
Results from the research indicate that the American Association of State
Highway Transportation Officials Load and Resistance Factor Design (AASHTO
LRFD) Specifications can be used to estimate the mechanical properties of SCC for a
concrete compressive strength range of 5 to 10 ksi (34 to 70 MPa). In addition, the
research team developed prediction equations for concrete compressive strength ranges
from 5 to 16 ksi (34 to 110 MPa). With respect to shear characteristics, a more appropriate expression is proposed to estimate the concrete shear strength for CC and
SCC girders with a compressive strength greater than 10 ksi (70 MPa). The author found
that girder-deck systems with Type A SCC girders exhibit similar flexural performance
as deck-systems with CC girders. The AASHTO LRFD (2006) equations for computing
the cracking moment, nominal moment, transfer length, development length, and
prestress losses may be used for SCC girder-deck systems similar to those tested in this
study. For environments exhibiting freeze-thaw cycles, a minimum 16-hour release
strength of 7 ksi (48 MPa) is recommended for SCC mixtures.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-2008-12-134 |
| Date | 14 January 2010 |
| Creators | Kim, Young Hoon |
| Contributors | Hueste, Mary Beth D., Trejo, David |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation |
| Format | application/pdf |
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