[M-IS05] Geomaterials in cultural heritage: weathering, investigation techniques, and conservation

[MIS05-05] MORPHOLOGICAL CHARACTERISATION OF BULLET AND SHRAPNEL IMPACTS IN STONE-BUILT HERITAGE

*Miguel Gomez-Heras¹, Riccardo Rocca², Jorge L. Giner-Robles¹, Laura Lopez-Gonzalez³ (1.Universidad Autonoma de Madrid, 2.Independent Geologist, 3.Independent Architect)

Keywords:Digital imaging, 3D scanning, Morphometric analysis

Bullet and shrapnel impacts from past conflicts are frequently found in stone-built heritage. These impacts are traces from the history certain monuments witnessed or suffered, therefore, their conservation needs to be considered. For this reason, it is necessary to document and perform a morphological characterisation of these features in addition to assessing how the impacts may be changing the mechanical properties of stone. The morphological characterisation can also inform on the type of projectiles and their trajectory, offering data on the history of past conflicts, This communication presents the morphological characterisation of bullet and shrapnel impacts in several monuments in the city of Madrid (Spain) from two different conflicts: the Peninsula War (1808-1814) and the Spanish Civil War (1936-1939). Examples from locally important as well as World Heritage monuments are included. Photogrammetric techniques at different scales as well as IR scanner were used to create Digital Elevation Models of the projectile impacts and evaluated in terms of accuracy, processing time and quality of the model obtained. Once the morphological analysis was performed, an assessment of the type of information obtained on projectile type and direction, as well as likelihood of the conflict that generated it when traces of several are present.

This research used equipment from UAM`s 3D Laboratory funded by the Unidigital program of the Spanish Universities ministry with funds from the EU's Recovery, Transformation and Resilience Plan - NextGeneration EU