Title: Case Studies in Structural Repair of Pretensioned Concrete Products
Date: March-April, 1999
Page number: 74-79
Author(s): Alan S. Hoback, Alaa I. Hermiz
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Case studies show various types of repairs that are sometimes necessary to rectify precast, prestressed concrete products. The cases show types of damage that can be caused by overloading, underdesign, quality control errors, accidents, and unanticipated events. The types of repair methods discussed are epoxying cracks, applying patches, enlarging the member with steel, and adding supplementary structural members. A precast member that is only slightly damaged can simply be patched or epoxied once the source of damage is removed. One case is found to be not repairable and the member is recast due to the severity of the defect and the time and cost involved in repairing it. It is found that damage may be limited by meticulous production and quality control, good communication with erectors, and careful detailing and testing of new design concepts.
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