Reduction of earthquake risk of the National Palace of Sintra in Portugal: The palatine chapel

Abstract

Protecting Cultural Heritage (CH) sites is an important and demanding task. One of the threats with the most disastrous consequences to the CH is the seismic action, as already confirmed in past events around the world. In the case of historical buildings made of masonry and timber, the deterioration of the structural elements constitutes an increased threat to the CH, which enhances their seismic vulnerability. In this framework, this work presents an example of good practices in seismic risk reduction using the case study of the palatine chapel of the National Palace of Sintra, classified as national heritage. The study started by reducing the uncertainties related to the material properties and structural characterization of this type of constructions through a visual inspection, complemented with in-situ experimental tests, to assess the geometry, constitution and state of conservation of masonry and timber elements (the later existing at the roof and inside the chapel). The results were used for the construction and calibration of reliable numerical models, as well as for the definition of rehabilitation actions. After performing the structural assessment of the chapel and identifying the most vulnerable parts, strengthening techniques compatible with the building characteristics and cultural importance are suggested.