Browsing by Author "Palazzi, Nuria Chiara"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
- ItemA new method for assessing compatibility of consolodation procedures with conservation principles: Intervention Qualitiy IndexLlera Martin, Juan Carlos de la; Palazzi, Nuria Chiara; Misseri, Giulia; Sandoval, Cristián; Tonietti, Ugo; Rovero, LuisaIn current times, built heritage is being lost at an alarming rate due to natural and human hazards. Policies for its protection and rehabilitation involve, among other things, challenges related to the refinement of suitable structural strengthening approaches. The arduous balance between gaining acceptable safety levels for occupants without deploying intrusive devices, inconsistent with conservation principles such as those of the ICOMOS charters, is not a simple task. The interest and efforts of the scientific community in this regard have been increasing for decades, but still, it is the structural professional´s responsibility and experience which must define this arduous balance on a case-to-case basis. This study addresses the question: How can the quality of structural rehabilitation interventions be assessed in light of conservation principles such as those given by ICOMOS? Here, a preliminary method - called “Intervention Quality Index” (IQI) method is proposed. It assesses the restoration intervention quality in relation to: (i) the level of compliance given by the conservation´s principle score (conservation´s factor, CF); and (ii) the current state of conservation of the monument (safety factor of building considering the seismic intensity, Δs). The IQI method considers the compliance level of the designed reinforcement with conservation principle, formalized through the fulfillment of a category, i.e. respected, partially respected, and not respected. Then, these judgments are translated into scores and statistically evaluated. Scores are attributed in relation to the relevance of the fulfillment of a certain conservation principle (authenticity, minimal intervention and intrusiveness, compatibility, recognizability and reversibility) for the seismic structural safety point of view. Preliminary results show that an effective employment of traditional earthquake-resistant practices together with a wise use of modern retrofit strategies allow for the preservation and reinforcement of built heritage without harming its identity
- ItemA new procedure to derive typological fragility functions for unreinforced masonry structures: an application to a Chilean case(2025) Muñoz Gálvez, Juan Pablo; D’Ayala, Dina; Palazzi, Nuria Chiara; De La Llera Martín, Juan CarlosThe assessment of the seismic fragility of unreinforced Masonry (URM) buildings in cities, using advanced numerical approaches, is hampered by the complex connectivity which develops with the diachronic process of urban growth and regeneration. The building stock forming 43 urban aggregates in the historic neighborhood of Yungay in Santiago, Chile, is the focus of this manuscript. The Failure Mechanism Identification and Vulnerability Evaluation method (FaMIVE), a mechanical approach based on limit-state analysis and failure modes, determines the collapse load factors and derive capacity curves for each of the 423 structures surveyed and analyzed. The objective of the study is to correlate specific sets of architectural features of these buildings to their seismic performance as represented through fragility functions. To this end we have introduced a new selection algorithm to automatically group the buildings using an optimal logic tree analysis (LTA). As a result, we obtain clusters of capacity curves using the observable properties of the façades as the decision variables of the LTA, while minimizing the variability of the parameters which define the capacity curves. The median capacity curve of each cluster is then used to derive Analytical Fragility Functions (AFFs), using a capacity-demand approach, which considers different sets of nonlinear spectra. The structure of the LTA is observed to be adequately preserved for fragility functions, fully justifying the subdivision in clusters. The aim of this work is to provide the data to prioritize mitigation strategies that enables us to preserve this heritage, as well as that of other similar historical urban areas in Chile and Latin American cities, which bear a strong architectural resemblance since their foundation
- ItemIntervenciones estructurales en la Basílica de la Recoleta Dominica en Santiago de Chile. Una revisión histórica y crítica(2024) Barrientos, Marco; Palazzi, Nuria Chiara; Alvarado, Rolando; Sandoval Mandujano, Cristián EliseoUnreinforced masonry (URM) historic churches are highly seismic vulnerable buildings due to its structural and material features. This condition partially explains the irreversible cultural heritage loss in Chile. After earthquakes, many URM churches have been strengthened with reinforced concrete (RC) elements as a seismic proof strategy. In this context, this paper aims to exam-ine the Recoleta Dominica basilica, as a prominent building with architectural, historical, and constructive attributes with efficient seismic performance along years as well, as reported after the 1985 and 2010 megathrust earthquakes. Its seismic performance can be explained by the RC strengthening elements added after the 1927 earthquake, and later 1981-1982 and 2000 structural interventions, avoiding local collapses as serving its conservation. The paper concludes by highlighting the 1927 RC project impact, its early technique reflected on its structural design criteria and following the original building nature. Some other studies in this research line may contribute to a better understanding of the inherited scopes involved in any structural RC project, its impact on the architectural features, the seismic-resistant improvements, and its cultural preservation.
- ItemNon-destructive testing and kinematic limit analysis applied to a historic masonry church early intervened with RC elements(2025) Alvarado, Rolando; Barrientos, Marco; Suazo, Antonio; Menanno, Giovanni; Pérez Pinedo, Luis Elías; Palazzi, Nuria Chiara; Sandoval Mandujano, CristiánThis article assesses the structural condition of a historic unreinforced masonry (URM) church whose original earthquake-resistant system was strengthened with reinforced concrete (RC) elements after the 1927 Mendoza earthquake. This early intervention, which took place between 1927 and 1930, consisted of RC frames formed by beams and columns embedded in the existing masonry. Since then, the church's seismic performance has been satisfactory, presenting minor damage after significant earthquakes. Despite its successful seismic performance, this church-and its strengthening strategy- has not been studied in depth. Due to the limited structural information available, a multidisciplinary study involving several non-destructive tests (NDT) in the church was conducted to understand its current structural state and reduce information gaps derived from historical sources and visual on-site inspection surveys. NDTs included the use of Terrestrial Laser Scanner (TLS), Unmanned Aerial Vehicle (UAV) photogrammetry, and Ground Penetrating Radar (GPR), among others. To assess the effectiveness of RC interventions, seismic behavior before and after the different retrofitting interventions was compared through linear kinematic analyses of the main failure mechanisms observed. The research results show that RC interventions increased the spectral accelerations required to activate overturning mechanisms in the macro-elements identified in the church, with safety indexes exceeding 1.0 for most RC-intervened macro-elements. The latter indicates that these elements are safe under the seismic loads specified by the Chilean code for heritage structures.
- ItemOn the role of planning policies in the seismic vulnerability of historic urban areas: evidence from Santiago, Chile(2024) Palazzi, Nuria Chiara; Amoruso, Giorgia; Baquedano-Julia, Pilar; Ferreira, Tiago MiguelThis research presents an interdisciplinary study on the impact of planning policies on the seismic vulnerability of historic areas, encompassing architecture, urban planning, and engineering aspects. It examines the spatial and temporal dynamics of urbanization and population growth, which alter cities' seismic exposure and vulnerability over time. Urban and engineering research methods are used to assess the seismic vulnerability variability in Yungay Quarter, a historic district west of downtown Santiago, Chile, with buildings constructed between 1839 and 2022. The study begins with a thorough review of Chilean urban planning policies and building regulations, combined with a detailed survey of the construction features in the historical neighborhood to classify building types. Next, the macro-seismic method is applied to a representative sample of 484 buildings to calculate vulnerability indices for unreinforced masonry and reinforced concrete structures, which are then used to estimate damage distributions. Seismic fragility curves for each building class are derived based on peak ground acceleration. These fragility curves are incorporated into risk assessments for potential ruptures along the San Ramon, Santiago splay and a deep intra-slab splay fault. The resulting risk scenarios can guide future urban planning policies and processes affecting this historical urban center. The innovations introduced by this work include a summary of how changes and updates to planning policies have influenced construction practices in the Yungay Quarter from 1839 to 2022 and the translation of these urban changes into variations in building fragility functions, enabling a comprehensive assessment of the potential impacts on these buildings from various potential.
- ItemSeismic Vulnerability Assessment of Unreinforced Masonry Churches in Central Chile(Springer Cham, 2019) Palazzi, Nuria Chiara; Rovero, Luisa; Tonietti, Ugo; Llera Martin, Juan Carlos de la; Sandoval Mandujano, CristiánIn the central region of Chile, the unreinforced masonry (URM) churches underwent extensive structural damage during the 2010 Maule earthquake (Mw 8.8), highlighting the importance of implementing seismic risk reduction plans. These religious buildings are characterized by profound typological and constructive peculiarities, originated by the combination of the local build culture with European architectural revivalisms(i.e., Neo-Baroque, Neo-Classic, Neo-Renaissance and Neo-Gothic)during the Spanish domination (1536–1818). The uniqueness of this heritage and the seismic risk of the Chilean territory lead to the need to define a systematic method to assess the seismic vulnerability of the Chilean URM churches. In this paper, some results of an in-depth investigation on a representative stock of churches are reported. The investigation was based on a database implementation with geometrical, constructive, and structural characteristics of 40 URM churches in the Metropolitan Region of Chile. A preliminary qualitative assessment of the seismic capacity of these churches is provided using a survey of geometric indices. Than specific damages observed after the 2010 earthquake have been related to the recurrent failure mechanisms of masonry structures, taking into account 21 local mechanisms involving the macro-elements of the churches. The average level of damage suffered by each church was calculated through the global damage index and a histogram of damage levels frequencies has been arranged. These results are preliminar suitable probabilistic tools to support seismic risk reduction plans.