Earthquake risk scenarios of the Ciutat Vella District in Valencia, Spain

Abstract

According to the United Nations Office for Disaster Risk Reduction cities must take measures to anticipate disasters and mitigate their impact, protecting homes and cultural heritage, minimizing losses due to earthquakes and other threats. After the recent earthquakes in historical city centres, the evaluation of the seismic risk, even in regions of low or moderate seismicity, is imperative, being damage assessment and loss estimation essential for its reduction. In this paper the seismic risk analysis of the residential buildings in the Ciutat Vella District in Valencia, with great historical and architectural value, is presented. The vulnerability of Ciutat Vella has been assessed with the Vulnerability Index Method establishing the seismic quality of the residential buildings according to their structural typology, conservation status, age and geometry; identifying the most vulnerable buildings. Damage probability matrices have been obtained for the deterministic and probabilistic earthquake scenarios, estimating for each of them, the seismic risk in terms of direct social and economic losses, mapping the results using a GIS system tool. Results confirm that the vulnerability of the building stock in Ciutat Vella is high being the seismic risk significant. In the event of an earthquake, many residential buildings included in the Catalogue of Listed Buildings of the Special Protection Plan of Ciutat Vella will be damaged. A detailed analysis of the most vulnerable buildings will provide criteria for intervention to enhance their structural seismic response, safeguarding the architectural heritage and contributing to the reduction of human and material losses.

Earthquake Risk Scenarios in Urban Areas: A Review with Applications to the Ciutat Vella District in Barcelona, Spain

“…Chiefly, the VIM method has been applied in European and African cities of the Mediterranean region. Some examples are the assessments carried out in the cities of Al Hoceima and Imzouren in Morocco (Cherif et al, 2017), and in the cities of Lorca (Tomas et al, 2017), Barcelona (Lantada et al, 2009a), Valencia (Guardiola-Víllora andBasset-Salom, 2015) and Granada and Velez in southern Spain (Feriche, 2012 andFeriche et al, 2009). Moreover, the VIM has been used in vulnerability assessments of the current building stock in historical centres, as in the ANTAEUS Project (Uva et al, 2016) in the Province of Foggia (Puglia, Southern Italy); and for the vulnerability assessment of old masonry buildings in the historical centre of Faro (Maio, 2016) and Lisbon (Simoes et al 2016) in Portugal.…”

“…Results from these kind of assessments were also used for Valencia's Special Plan against seismic risk, approved in 2011, which recommends the creation of specific plans for several municipalities. The study carried out in the residential district of the Eixample by Guardiola-Víllora and Basset-Salom (2015) led to the project being extending to the rest of the city of Valencia, and studies by Feriche (2012) and Feriche et al (2009) helped to improve local seismic emergency planning in Granada and Velez cities in southern Spain.…”

An Enhanced Earthquake Risk Analysis using H3 Spatial Indexing

“…Examples include probabilistic seismic hazard analysis (PSHA) and seismic loss estimation. [11] The grid system is a method of dividing a geographical area into a regular grid of cells, typically in a square or hexagonal shape, for the purpose of spatial analysis and mapping. The grid system has a long history in geographical information science and has been widely used in a variety of applications, including land-use planning, environmental modeling, and risk assessment.…”

Mapping an Urban City Centre for Seismic Risk Assessment: Application to Valencia (Spain)

“…-Despite the influence of the construction techniques, the state of preservation is a determinant factor in the buildings seismic performance, especially in the case of unreinforced masonry (URM) buildings, not only for the building itself, but also due to the lack of the stabilizing contribution of neighbouring cells when the maintenance level is bad or the building is ruined (Carocci, Lagomarsino, 2009;Basset-Salom, Guardiola-Víllora, 2013;Guardiola-Víllora, Basset-Salom, 2019). Figure 3 shows buildings of the same typology but with different state of preservation.…”