For this project, an array of nondestructive tests including live load testing, strain monitoring and acoustic emission monitoring were conducted to assess the performance of a repair performed on a section of a post-tensioned box-girder bridge; re-grouting of voids found in of post-tension duct. As such, the objective of this study is to compare the performance of the repair in-situ as part of the bridge section structural response to that of a section know to be sound. The structure’s strain response at critical positions, such as midspan and near supports of tested span, were recorded during a live load test conducted over a span of the bridge. In addition to strain monitoring, acoustic emission (AE) monitoring was also used as a supplement test method to the standard load/deformation analysis to evaluate the performance of the repaired member. A comparison analysis between the strain responses at different locations and acoustic emission intensity analysis was carried out based on recorded strain response and AE data during load test. The results of the structure’s strain response indicate an elastic behavior of the tested bridge span under three different load levels. From the obtained AE monitoring data, there is a good agreement with structural strain response by the fact that each cluster of AE data from different bridge load test levels matches up well with the peak in structure strain response. Moreover, the intensity chart shows the trend in which higher intensity points moving towards the top right corner and lower intensity points moving towards bottom left corner. The methodology developed and results obtained will serve as a comparative benchmark for future live-load testing to be performed in the near future.

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