GPR assessment of the modernist Santa Creu i Sant Pau hospital in Barcelona: GPR application in cultural heritage

The Santa Creu and Sant Pau hospital is a monumental ensemble built in Barcelona between 1901 and 1930 on the site where six small medieval hospitals were founded in 1401. It is a complex of buildings which represent the art nouveau architecture in Barcelona. It was declared World Heritage site by the UNESCO in 1997. In the previous eight decades of clinical activity, modernist buildings have experienced numerous architectural modifications that have affected both their structures and ornamental elements. The deterioration of the buildings became apparent in 2004. In this situation, in 2006 a master plan to assess the state of the hospital evidenced the critical state of many of its pavilions, and therefore a complete rehabilitation project for the entire ensemble was approved. The assessment of some specific structural elements, that is spandrels and columns, located in the Pharmacy pavilion and in the hospital church, has been performed and evidenced the presence of metallic elements, sub-structures and, in some cases, corroded iron elements, embedded in the masonry structure. A detailed description of these embedded elements and some damaged areas inside the columns was performed through a non-destructive prospection with ground penetrating radar. A 1.6 GHz nominal center frequency antenna was used in this assessment.