Reusability and Impact Damage Repair of Twenty-Year-Old AASHTO Type Ill Girders

Prestressed concrete has been used as a bridge construction method in the United States since 1949. Presently, there are thousands of pretensioned prestressed concrete bridges in service in North America. Each year, approximately 200 girders are damaged as a result of impact damage (primarily overheight vehicles striking a bridge from below). This report describes the results of a four girder test series used to evaluate impact damage and effectiveness of repairs. The girders used for the study were fabricated in 1967 and placed into service. The girders were removed from service in 1984 as a result of a road realignment project. The objectives of the research project were to: 1) determine the effective prestress in the strands after 20 years; 2) determine the influence of impact damage on girder performance; 3) evaluate the performance of two impact damage repair schemes under static, fatigue and ultimate loadings; and 4) develop a model to estimate the strand stress ranges in damaged girders.