DIGITAL ANALYSIS WITH 3D SCANNING AND THREE-DIMENSIONAL MODELLING OF THE MAIN CHURCH OF ST. MARY – THE OLD CATHEDRAL, CARTAGENA (REGION OF MURCIA, SPAIN)

Abstract. The former Church of St. Mary, known as the Old Cathedral, in Cartagena (Region of Murcia, Spain), is a construction from the beginning of the 13th century, but it was transformed in the 16th century and rebuilt at the beginning of the 20th century. The bombings occurring during the Spanish Civil War caused the partial collapse of the building and the state of ruin that it currently presents. It is protected as a PCI with the category of monument. A Master Plan is currently being developed that should lead to the recovery of the building. The "Thermal Analysis and Geomatics (TAG)" Research Group of the Polytechnic University of Cartagena has collaborated in the drafting of the Master Plan with a planimetric survey and graphic analysis of the entire building. For this purpose, digital terrestrial photogrammetry techniques and a 3D laser scanner compatible with classical topography have been used, in order to obtain an accurate three-dimensional model. All this graphic information has been contrasted with the historical, typological, material and constructive information currently available about the building, which has facilitated the making of an exhaustive three-dimensional analysis that permits us to know this ancient Cathedral in depth. This paper will describe the work methodology followed, the technical means used and the results achieved, which have been incorporated into the Master Plan that is being prepared. Undoubtedly, the digital analysis has helped to obtain a better general understanding of the building and to be able to propose a correct formal, structural and material recomposition.