Page - 775 - in Book of Full Papers - Symposium Hydro Engineering

[2,3], cameras with telescopic lenses [4] and terrestrial laser scanners (TLS) in the past [5]. Fig. 1: Dam surveillance as defined by ICOLD [1, p. 4] The mentioned technologies imply highly sophisticated data acquisition and processing methods, requiring significant investments of money and time. For this reason, we propose a method, in which we use a sensor commonly used by dam operators in order to accomplish the same as by using UAVs and TLS. The recent developments of total stations (TS) [6] brought scanning and image functionalities, and thus opened up new fields of application such as surface mapping. In this paper, we present an approach for surface documentation and evaluation with modern total stations, which we apply to an Austrian arch dam. We present a workflow to compute a photorealistic three-dimensional model. Additionally, we introduce a novel system concept for automatic on-site detection and mapping of concrete deficiencies with high-resolution. By applying state-of-the-art processing techniques to the scan and image data and by exploiting the hardware features of the hybrid instrument, we demonstrate the potential for a surface monitoring solution. This solution enables merging the two major pillars of dam surveillance, monitoring and visual inspections. The proposed system enables change detection analysis of the dam’s surface and hence a novel tool to contribute to an objective overall assessment of dam safety. 775