ABSTRACT
Long-term serviceability of the FRP retrofitted structure is not easy to predict analytically or in a laboratory because in-service conditions of bridges are far more severe than the laboratory environment and load-transfer and deterioration mechanisms cannot be accurately incorporated in analytical models. It is also extremely difficult to simulate environmental fluctuations, freeze-thaw cycles, deterioration, and vehicular traffic under laboratory conditions. For these reasons, evaluation of retrofitted bridge structures/elements is usually based on their in-service performance and behavior. Field testing using controlled loads predominantly is used for this purpose. Generally, these load tests are conducted at time intervals under similar loading conditions and structural behavior is monitored for changes. If no changes have been observed and the structure’s behavior duplicated previous behavior, the effectiveness of the retrofit system could be concluded. Considerable care should be taken when planning testing to monitor in-service structural behavior as it may require instrumentation to survive exposure to severe and adverse weather conditions for a long time.
