Static truck loading testing is a field experimentation technique used widely to evaluate bridge structural characteristics. Measurement is often performed on the bridge for displacement and/or strain at selected points. Traditional instrumentations for girder deflection measurement include linear variable differential transformers (LVDT) or cable extension transducers. The techniques require access to the bridge girders and possibly interruption of traffic. It is different to implement for those highway bridges with busy underpass traffic flows. This paper presents a study of girder deflection measurement testing on a hybrid HPS bridge. A commercially available Light Detection and Ranging (LiDAR) system was introduced to measure bridge deformation under static truck loads. This non-contact LiDAR scan is an optical remote sensing technology developed for range measurement. Cable extension transducers were also installed under the girder bottom flanges to measure girder deflection under given truck loads. Three different truck load configurations were designed for the tests. Girder displacement results obtained from both LiDAR scan and the transducers were compared. The results are also compared to a full-scale Finite Element (FE) bridge model. It is conclude that the LiDAR scan is an effective measurement technique in bridge load testing.

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