Performance of Bridge Decks and Girders with Lightweight Aggregate Concrete (2 Volumes)

摘要

In the Kettelhut Structural Engineering Laboratory twelve reinforced and four prestressed concrete beams were tested to failure. The experimental shear capacities were compared to calculated shear strength values from the 1995 American Concrete Institute Building Code and the 1994 AASHTO LRFD Standard Specifications.nBased on the test results from this study it is recommended that water-cementitious ratio be used for proportioning of lightweight concrete mixes and that trial batches be prepared and tested before actual field application. To ensure adequate durability, lightweight aggregate concrete should be allowed to dry before exposing it to cycles of freezing and thawing. On the structural side, both the ACI and the AASHTO LRFD Specifications were found to yield conservative estimates of the shear strength of LWC reinforced and prestressed beams provided adequate detailing of the reinforcement is provided. More work is needed regarding the minimum amount of shear reinforcement for high strength lightweight concrete beams.