Abstract
Abstract. One of the fields where 3D modelling has an important role is in the application of such 3D models to structural engineering purposes. The literature shows an intense activity on the conversion of 3D point cloud data to detailed structural models, which has special relevance in masonry structures where geometry plays a key role. In the work presented in this paper, color data (from Intensity attribute) is used to automatically segment masonry structures with the aim of isolating masonry blocks and defining interfaces in an automatic manner using a 2.5D approach. An algorithm for the automatic processing of laser scanning data based on an improved marker-controlled watershed segmentation was proposed and successful results were found. Geometric accuracy and resolution of point cloud are constrained by the scanning instruments, giving accuracy levels reaching a few millimetres in the case of static instruments and few centimetres in the case of mobile systems. In any case, the algorithm is not significantly sensitive to low quality images because acceptable segmentation results were found in cases where blocks could not be visually segmented.
Highlights
During the last years, the creation and application of 3D models to many documentation, inspection and monitoring tasks has provoked that reverse engineering gained popularity outside of the geomatic domain
Specific applications to structural engineering can be seen in Riveiro et al (2011a) and Riveiro et al (2011b) who developed a methodology that allows point clouds acquired by terrestrial laser scanning and photogrammetry, respectively, to be converted into metric images suitable for subsequently stability analysis of masonry arches
For the investigation presented in this paper, the point cloud of one of its vaults was exported to ASCII in order to automatically map all its voussoirs
Summary
The creation and application of 3D models to many documentation, inspection and monitoring tasks has provoked that reverse engineering gained popularity outside of the geomatic domain. Building reconstruction has been one of the most popular fields of research during the last years (Haala et Kada, 2010) Within this field, many efforts have been aimed to façade modelling (Becker, 2009; Pu et Vosselman, 2007) due to the increasing demand of realistic and accurate city models. Many efforts have been aimed to façade modelling (Becker, 2009; Pu et Vosselman, 2007) due to the increasing demand of realistic and accurate city models Most of these approaches deal with reconstructing façade components such as walls, doors or windows, while no attention is paid to blocks forming masonry walls, especially relevant in heritage buildings. Laser scanning is gaining popularity in the field of structural and civil engineering, the process still demands a highly manual intervention during the processing for a suitable conversion
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
