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21 Table 9. (Continued). Number SCC Test Test Size/volume of Property of samples behavior method age specimen per mixture 3 steam cured At release 3 air cured 3 moist curedd 7 days 3 air curede 4 8 in. Compressive AASHTO 3 moist curedd (100 200 mm) 28 days strength T 22 3 air curede cylinders 3 moist curedd 56 days 3 air curede At shear 3 moist curedd testing 3 air curede 2 steam cured At release 2 air cured Mechanical 2 moist curedd 7 days properties 2 air curede 4 8 in. Modulus of ASTM 2 moist curedd 28 days (100 200 mm) elasticity C 469 2 air curede cylinders 2 moist curedd 56 days 2 air curede At shear 2 moist curedd testing 2 air curede 3 steam cured At release 3.9 3.9 3 air cured d 15.7 in. AASHTO 3 moist cured (100 100 Flexural strength 28 days T 97 3 air curede 400 mm) 3 moist curedd prisms 56 days 3 air curede Temperature rise 6 12 in. (semi-adiabatic 1 (150 300 mm) Hydration conditions) cylinders kinetics AASHTO Setting time 1 Sieved mortar T 197 Transfer length, 3-point Full-scale flexural cracking, flexural & 2 SCC girders 2 HPC girders AASHTO-Type Structural and shear capacity shear testing II girder with performance 31 ft (9.4 m) 2 SCC girders Camber growth in length 2 HPC girders d 18 hours of air curing followed by moist curing at 100% RH and 73F (23C) e 18 hours of steam curing followed by air curing near the corresponding girderat 50 4% RH and 73 4F (23 2C) determine the compressive strength and modulus of elastic- 2.4 Guidelines for Use of SCC ity at 7, 28, and 56 days, and also at the age corresponding to in Precast, Prestressed the time of testing the girders. The tests on beam specimens Concrete Bridge Elements provided data on the modulus of rupture at the time of pre- stress release and at 28 and 56 days. Based on the results of the literature survey and the labo- ratory evaluation, guidelines were developed for the use of SCC in precast, prestressed concrete bridge elements. The 2.3 Approach for Relevant Changes guidelines, provided in Attachment B, include information to AASHTO LRFD Bridge Design on the selection of material constituents, mixture propor- and Construction Specifications tioning, and testing of SCC. Performance-based specifica- To recommend relevant changes to AASHTO LRFD Bridge tions of fresh and hardened concrete properties are provided, Design and Construction Specifications, the specification and special placement and construction issues are discussed. sections that relate to the proposed research were examined. The guidelines deal with the early-age properties, mechanical Relevant changes are integrated in Attachment A. properties, durability, and structural performance of SCC.