Capturing dam geometry by Lidar and multibeam technology for visualization of structural deformations - Case study Dam Bečej

Abstract

Bečej Dam is a concrete dam on the Tisa River, which has been monitored since the 1980s through the monitoring of point-mark position vector changes on the dam body in 2D and 1D coordinate system. Conventional geodetic measurements are applied, and displacement vectors of point-mark are determined by the congruence method over a long period of time. The network of geodetic points that defines the local coordinate system has been designed and realized. This paper will present the results of the 2019 measurements. The following measurements have been performed in the geodetic network: GPS measurements for vectors, measurements of lengths and angles, and measurements of the height differences. A complete scaning of the broader dam body area and all access facilities, reservoir and its bottom was performed using the Lidar and multibeam technology. The visualization of the dam body and reservoir lake were presented in a 3D model, based on the Lidar and multibeam technology results. Displacement vectors of point-mark are shown in the 3D model created. The example of the Bečej dam demonstrates the capabilities of modern Lidar and multibeam technology, the creation and visualization of 3D object models and the presentation of all potential geometry changes that are important for the safe maintenance and management of the feature.