http://orcid.org/0000-0003-4140-9374
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Abstract
Terrestrial laser scanning (TLS) technology has various applications due to its capability of acquiring detailed 3D information about objects within a limited time-period. Yet, it is not widely used for the deformation monitoring of structures. To investigate the suitability of TLS for such tasks, a time-of-flight type Leica ScanStation C10 was used to determine the vertical deformations for two bridge load tests in Estonia, namely for the Loobu highway bridge and the Tartu railway overpass. The TLS results were verified with precise levelling, reflectorless tacheometry and dial gauges. Generally, deformation estimates obtained from TLS and other measurement techniques show sub-millimetre agreements (in terms of standard deviations). The maximum differences between the TLS and precise levelling results were 3.4 and 0.8 mm for the Loobu and the Tartu study, respectively. Since TLS has not yet reached the same accuracy as conventional geodetic high-precision techniques, it cannot fully replace them in high accuracy applications. However, TLS can be considered a complementary survey method for load tests as it provides valuable entire surface covering 3D information.
Acknowledgements
The TLS Leica ScanStation C10, the total stations Trimble S6 and Trimble M3 and the accompanying licensed software used in this study were purchased within the framework of the Estonian Research Infrastructures Roadmap object Estonian Environmental Observatory (project No. AR12019) and maintained within the IUTT2 project. The study was supported by the Estonian Environmental Technology R&D Program KESTA, research project ERMAS, AR12052. The invaluable comments of the three anonymous reviewers are appreciated and lead to significant improvements of the manuscript.