Preliminary Assessment on Seismic Vulnerability of Masonry Churches in Central Chile

ABSTRACT

The 2010 Maule Chile earthquake (Mw 8.8) caused extensive structural damage to the built heritage. In particular, the poor seismic performance of a set of unreinforced masonry (URM) churches highlighted the need to implement protective and safety strategies in order to preserve these buildings which exhibit unique constructive and typological features, as a result of a combination of Chilean and European construction cultures.

The peculiarity of this heritage and the high seismic hazard of Chilean territory have motivated the present study which aims to apply systematic procedures to assess the seismic vulnerability of these buildings. This article is of archival nature and presents a complete database generated from the geometrical, constructive, and structural characteristics of a representative stock of 106 churches located in central Chile, with the goal of proposing fragility curves to be used in seismic risk assessment. Considering variables related with geometrical, architectonic, and stylistic features, as well as damage levels for the 2010 Maule earthquake, this church sample is classified into three homogenous groups: colonial, neo-classic, and neo-gothic. Moreover, a preliminary qualitative assessment of the seismic capacity of these structures is provided using a survey and analysis of geometric indices for each of the three selected groups.     

Increasing livelihood vulnerabilities to coastal erosion and wastewater intrusion: The political ecology of Thai aquaculture in peri-urban Bangkok

Most livelihood research focuses on micro-level decisions affecting occupations but fails to examine wider scale processes that shape markets, institutions, and thus livelihood choices. A political ecology framework can help address this gap by providing ways to analyse how multi-scalar and extra-local practices, policies, and discourses affect local-level socio-environmental outcomes. In the qualitative research reported here, that framework is applied to Tha Kam, a peri-urban coastal sub-district of Bangkok, where most residents are small-scale aquaculture farmers. These farmers have experienced precipitous drops in incomes because of two major environmental changes: coastal erosion and wastewater intrusion. The causes are multiple and complex, and many originate not from practices within Tha Kham but from challenges present at a larger scale or that start upstream. The political and economic drivers of these problems stem from Thailand’s fragmented vertical and horizontal governance structure, unequal class relations in which smallholder farmers and peri-urban residents are marginalised, and lack of accountability and representation. This combination of multi-scalar factors and power imbalances has contributed to evolving injustices of peri-urbanisation, all of which are profoundly geographical in their significance.     

Grief as method: topographies of grief,care, and fieldwork from Northwest Arkansas to New York and the Marshall Islands

Abstract

When we grieve during fieldwork, our grief forms new geographies of knowledge production and emotion. In this article, I use autoethnography to theorize my grief during fieldwork following the death of my sister. I examine grief’s methodological implications using the concept of ‘grief as method,’ an emotionally-inflected practice that accounts for the vulnerability produced by grief. By centering vulnerability, ‘grief as method’ also urges researchers to consider the practices and politics of ‘caring with’ our research subjects and caring for ourselves, raising larger questions about the role of care in research. Furthermore, this article demonstrates how grief’s geographical features—its mobility, its emergence in new sites and landscapes, and its manifestation as both proximity and distance—shape ‘grief as method’ profoundly. I examine grief’s spatial implications by building on Katz’s ‘topography’ to theorize a ‘topography of grief’ that stitches together the emotional geographies of researchers, blurring both spatial divisions (‘the field’ vs. ‘the not-field’) and methodological ones (the ‘researcher-self’ vs. the ‘personal-self’). If we see grief as having a topography, then the relationships between places darkened by grief come into focus. Moreover, by approaching grief methodologically, we can better understand how field encounters—relationships between people—are forged through grief. ‘Grief as method,’ in offering a spatial analysis of grief’s impact on fieldwork, envisions a broader definition of what engaged research looks like and where it takes place.     

A Multidisciplinary Study on the Seismic Vulnerability of St. Agostino Church in Amatrice following the 2016 Seismic Sequence

ABSTRACT

The big earthquake of August 24, 2016 and subsequent major shocks severely damaged many historic villages in Central Italy and dramatically showed the intrinsic vulnerability of the diffused architectural heritage. The St. Agostino church is one of the collapsed historical buildings, being inside the epicentre village of Amatrice. During the long seismic earthquake swarm, progressively the church was damaged and monitored. This multidisciplinary study of the damage of the church includes correlations of all the data derived from three steps geomatics surveys (3D aerial and terrestrial models): the archival drawings and images documenting previous events distressing the building, the previous strengthening intervention, and finally the seismic site response analysis (from Amatrice’s accelerometric station). Through a back analysis carried out by a finite elements model, it was possible to understand the seismic vulnerability of this historical building, in relation to the previous interventions and damage events. The proposed methodology, based on the interdisciplinary data analysis, provides useful information for the next strengthening projects of damaged historical monument.     

Challenging the odds of vulnerability and resilience in lone migration: coping strategies of Zimbabwean unaccompanied minors in South Africa

ABSTRACT

Childhood vulnerability attracts more societal and scholarly attention than child resilience. This article presents experiences of some Zimbabwean Unaccompanied Minors (ZUMs) in South Africa as an example of children who adapt to living as migrant minors separated from their parents. Using life history and aspiration interviews with eighteen ZUMs, we explore their coping strategies to test theoretical perceptions about childhood vulnerability and expand knowledge of how they are being affirmed and/or challenged. With research conducted in Makhado (Louis Trichardt), a non-border town in South Africa, the article highlights the nuances of ZUMs living in-shelter with catered needs versus ZUMs living out-of-shelter and fending for themselves. The interconnected effects of this on the children’s agency, vulnerability and resilience, now and potentially in future are also explored. In engaging the philosophy that some childhoods are inherently difficult, the study confirms that some ZUMs cope successfully despite being caught-up in tensions between structure-agency and vulnerability-resilience. The coping strategies of ZUMs reinforced some forms of vulnerability, while they camouflaged or silenced others. This cautions against the adoption of uncritical, or generic views about children’s agency and capabilities. The study concludes that individual and societal context matter greatly in discourses about child agency, vulnerability and resilience.     

Seismic Vulnerability of Historical Masonry Aggregate Buildings in Oriental Sicily

ABSTRACT

The seismic vulnerability assessment of historical UnReinforced Masonry (URM) buildings is a very complex task since it is strongly related to a great variety both of geometrical layouts and of masonry mechanical characteristics. In this article, some results of a Catania University research project, denomined “FIR 2014”, focused on the seismic vulnerability estimation of historical buildings, built in Catania after the 1963 earthquake, are presented. First, a detailed typological analysis of the considered urban fabric, characterized by typical residential masonry buildings, has been performed. Such analysis allowed recognizing an elementary structural modulus, which has been studied according to different geometrical layouts representative of isolated or aggregate buildings. The results of nonlinear static analyses, performed by applying an innovative macro-element approach, allowed for the assessment the seismic vulnerability of typical URM buildings coherently to the Italian seismic code. The adopted macro-element strategy for the seismic assessment of aggregate masonry buildings, although related to a specific historical center, may be applied to similar urban fabrics and can also be used for the calibration and validation of fast seismic assessment strategies, particularly useful for the evaluation of the seismic risk at urban scale.     

Seismic Vulnerability Assessment and Retrofitting Strategies of Italian Masonry Churches of the Alife-Caiazzo Diocese in Caserta

ABSTRACT

Masonry churches represent the major part of the Italian architectural heritage. Recent earthquakes stressed the high vulnerability of these constructions, provoking heavy structural damage and valuable losses. Different approaches have been developed to assess seismic vulnerability of churches. In particular, the complexity related to more detailed models has induced to define simplified methods, which can be used at territorial scale for a preliminary assessment of structural capabilities of homogeneous assets aiming at providing possible post-earthquake damage scenarios and suggesting general interventions strategies. Therefore, the vulnerability assessment of churches is carried out by subdividing the buildings into separate macro-elements, accounting for different possible collapse mechanisms. In this article, a simplified procedure (M.I.T. 2011) has been applied with reference to churches located in Caserta District, particularly those of the Alife-Caiazzo Diocese, by using the MaChro form compilation, previously developed by the authors. The aim of the study is the application of the above procedure in order to verify the possibility to suggest suitable strategies of intervention for structural retrofitting and seismic risk reduction of the churches located in the area under investigation.     

Developing a Synthetic Index of Land Vulnerability to Drought and Desertification

This paper develops an index of the vulnerability of land to drought and desertification (LVI) for Italy. The index takes into account changes in climate, land use, vegetation cover, soil properties, and population during the period 1990–2000. The LVI was built up through a multivariate approach aimed at assessing the importance of the various indicators included in the synthetic index. Increasing land vulnerability was observed during this time, especially in dry areas of the southern regions. This is interpreted as a consequence of land management practices, agricultural intensification, population pressure, and bio-physical degradation. The LVI can be used in an integrated, decision-support system to evaluate the impact of mitigation policies in rural environments.