Masonry structures assesment and photogrammetry. Ca-se study: San Millán de Segovia = Evaluación de estructuras de fábrica y levantamiento fotogramé-trico. Caso de estudio: San Millán de Segovia

The advanced technology of the new photogrammetric systems, whose progressive improvements could be due to both better resolution of the new cameras and the recent development of sophisticated interpolation algorithms, permits nowadays register not only the general aspect of the building architecture plan and elevations but also, learning in detail the geometry of the parts that integrate the building, and more significantly, the main elements of its structure. In fact, it has a great interest in many areas, and specially in masonry structures, where stability analysis require detailed information about the structural joints of the materials that set the element as well as the specific geometry of the junction that appears between the contact of one block with another. In this work, we demonstrate that a complex photogrammetry technique can be used as a geometric base to analyze masonry structures. The San Millan de Segovia's church is used as an example of structure for the study. This study addresses the different parts of the process, from the photogrammetric lifting to the simplification processes used for implementing this procedure automatically to any type of structure, pointing out the operational simplicity that this technique allows.