Seismic vulnerability assessment of traditional timber frame and masonry wall buildings. Application to the historical centre of valparaíso, chile
- Autores: María Belén Jiménez Ramírez
- Directores de la Tesis: Luca Pela (dir. tes.)
- Lectura: En la Universitat Politècnica de Catalunya (UPC) ( España ) en 2021
- Idioma: español
- Materias:
- Texto completo no disponible (Saber más ...)
- Resumen
The seismic vulnerability of urban assets exposed to earthquake hazard represents a growing concern in the engineering field due to the potential risk of collapse for the buildings, and the associated devastating consequences for the inhabitants. This concern has led to the development of novel strategies for the assessment of the seismic vulnerability of the existing buildings. An accurate evaluation of the seismic vulnerability constitutes the point of departure for the implementation of the necessary mitigation strategies aimed at increasing the seismic resilience of the cities.
Seismic vulnerability assessment (SVA) at large-scale requires robust knowledge of the existing structural typologies, often biased by the intrinsic uncertainties related to local construction materials and techniques, especially in territories composed of historical and vernacular constructions. A propaedeutic stage of SVA is the definition of building taxonomies to characterize the structural features of the buildings and their main sources of vulnerabilities. This difficult task requires the availability of consistent technical data, which are commonly scarce in cities with historical constructions.
This doctoral thesis contributes to the development of suitable methodologies for the systematic surveying of urban buildings in historical urban centres, by proposing four complete survey forms for timber, masonry, reinforced concrete and steel/iron structural typologies. This tool aims to improve and optimize the complex process of collecting and gathering data about the structural characteristics of the existing building stock.
This thesis also contributed to the calibration of simplified numerical models for the assessment of the seismic vulnerability of traditional buildings composed of timber frame and masonry wall structures. The nonlinear behaviour is simulated through the adoption of Lumped Plasticity Models (LPM) for timber frames, and continuum Finite Element (FE) models for masonry walls. The calibration of these models is pursued based on rigorous comparisons with numerous experimental tests available in the scientific literature.
The developed simplified numerical models for timber frame and masonry wall structures are used to assess the seismic vulnerability of two existing buildings located in the historical centre of the city of Valparaíso, Chile. The numerical models are employed afterwards to analyse the different structural configurations of timber-masonry buildings of the study area. The examined structural configurations differ in the organization of the resisting systems, number of storeys, and presence of structural irregularities. The different pushover analyses show the influence of the aforementioned parameters on the seismic behaviour of the buildings.
This research proposes a tentative set of scores and weights for the application of the Vulnerability Index Method (VIM) to traditional buildings composed of timber frame and masonry wall structures based on a numerical investigation. The resulting VIM form is calibrated by applying the N2 method to determine the seismic performance of the representative typologies within the study area. This study is based on the results of a numerical study, unlike other available VIM forms available in the existing literature are based on past post-earthquake surveys of damaged buildings.
The thesis ends in a prospective study on the seismic vulnerability by VIM of 111 buildings located in three neighbourhoods of the historical centre of Valparaíso. This is an area of special interest, as it includes two of the main evacuation routes for the city in case of a tsunami, and congregate different typologies of heritage buildings, made of timber, masonry, and reinforced concrete. The obtained results are used to create seismic vulnerability maps in a GIS environment that may be used for future works aimed at the definition of proper policies for the implementation of mitigation strategies.
