Abstract

The authors present an analysis of the possibility to assess deformations and mechanisms of destructing bent reinforced concrete beams using the terrestrial laser scanning. As part of the experiments carried out at the Regional Laboratory of Construction of the Concrete Structures Division of the Civil and Environmental Engineering Faculty at Gdansk University of Technology, the reinforced concrete beams were subjected to destruction by bending and by shear. The process of press impact on the reinforced concrete beam was recorded using a terrestrial laser scanner within the frames of cooperation between the university and the manufacturer of the scanner. Development of scanning effects was performed using Leica Cyclone software and MeshLab (GNU General Public License). In order to verify the results, the independent recording of beam deflection was carried out with the use of extensometer and the recording with non-meter synchronous digital cameras was carried out and photos from these cameras were subjected to photogrammetric processing. However, the principal subject of this paper is to show the usefulness of laser scanning for the analysis of reinforced concrete beams damages and authors of this paper focused on this subject. The selection of reinforced concrete beam in this case was a conscious action, aimed at preparing the assessment of the suitability of laser scanning in reference to the element well described in the literature and known in the field of mathematical description of its destruction process. In the description of the experiment there are six stages of measurement mentioned for the reinforced concrete beam: from the zero condition (no force), through intermediate conditions up to the stage of destruction. Scanning was performed from one stable measurement station to avoid in processing the effect of correlation errors (matching and linking) of ScanWorld. Analysis of the materials from laser scanning allowed to assess the geometry of element subjected to destruction with an accuracy not worse than 1 mm. For this purpose, the method of spheres translation was developed and in its characteristic groups of points from scanning the spheres were described. Spheres centers grew to be geometrical element to be assessed on scans in subsequent measurement epochs.

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Authors (3)