Flood vulnerability and damage assessment of earthen architectural heritage of the Iberian Peninsula

Abstract

Earthen architecture is a building tradition that is part of the vast and varied cultural heritage of the Iberian Peninsula (Spain-Portugal). Historically, floods have posed a threat to this cultural heritage. Floods have often led to the loss of traditional monuments and buildings, as well as entire settlements. At present, climate change has increased the frequency and intensity of flood events, raising the risk of disappearance of built earthen architectural heritage. The effects of floods on these constructions are mostly manifested as damage to the superstructures. However, visible structural damage is often related to geotechnical problems triggered by flooding. Generally, earthen architecture is considered very vulnerable to the action of water due to the hygroscopic nature of the materials that constitute it. Nevertheless, many of these buildings have come to the present day, resisting the action of water, thanks to a process of adaptation and improvement carried out by humanity over the centuries. Against this background, the present study aims to analyze the impact of floods on earthen architectural heritage, through the development of a qualitative methodology to assess flood vulnerability of earthen structures. Through case studies in the Iberian Peninsula, visible damage to earthen constructions related to the superstructure-soil interaction and triggered by floods is analyzed, in order to highlight the vulnerabilities and resilience resources of this cultural heritage. Finally, strategies for flood risk mitigation and conservation criteria for earthen architectural heritage are proposed.