Search results for "Fragility"
showing 10 items of 75 documents
Nonlinear Response of RC Structures: Statistical Effects of Artificial Ground Motions
2020
The selection of seismic inputs for nonlinear dynamic analysis is widely debated, mainly focusing on the advantages and disadvantages provided by the choice of natural, simulated or artificial records. However, most of the available technical codes do not provide always the same suggestions and well-defined procedures for the generation of artificial ground motions. Considering that the strategy of the generation of accelerograms makes some doubts raise about the possible effect on the structural response, the work aims to investigate on the differences of the structural behavior by using accelerograms nominally equivalent but different in terms of stationarity. This paper presents a compar…
Out-of-Plane fragility of In-Plane damaged unreinforced masonry infills in low rise reinforced concrete buildings
2022
Unreinforced masonry (URM) is commonly used to make infill walls in reinforced concrete (RC) frame buildings. Such infill walls are highly vulnerable to out-of-plane (OOP) seismic loading and this can result in huge economic losses and human casualties. Therefore, fragility assessment of URM infill walls under seismic loads is important in view of performing large-scale risk analysis. In this paper, OOP fragility functions are provided based on a numerical investigation supported by a macro-element model. The fragility is calculated assuming the uncertainty in the geometric and mechanical properties of infills instead of the variability in the seismic input. Further, the effect of in-plane …
Out of plane fragility of infill walls with and without prior in-plane damage
2019
The paper presents the results of a probabilistic assessment framework aimed at evaluating out-of-plane fragility curves of infill walls which have suffered (or not) prior in-plane damage. Out-of-plane incremental dynamic analyses are performed based on a suite of 22 ground motion records. A recently developed in-plane / out-of-plane macroelement model is used to model masonry infills within frames. The outcomes show fragility curves representing the probability of exceeding out-of-plane collapse at a given earthquake intensity as a function of a different combination of geometrical and mechanical parameters, in-plane damage level and supporting conditions.
Out of Plane response of Unreinforced Masonry infills: Comparative analysis of experimental tests for the definition of strategies of macro modelling…
2022
During an earthquake, an interaction between the in-plane and out-of-plane seismic forces occurs and the infilled frames suffer damage in both in-plane and out-of-plane directions simultaneously. Particularly, the out-of-plane collapse of unreinforced masonry infill walls is critical even for new buildings complying with the modern seismic codes, resulting in high casualties and huge economic losses. However, the out-of-plane behaviour of infill walls is yet not fully understood. This study is therefore aimed towards characterizing the out-of-plane seismic capacity of unreinforced masonry infill walls. First of all, available out-of-plane experimental tests performed on unreinforced masonry…
Effect of the different data survey scale on assessment of seismic exposure and vulnerability of the historic center of Caltabellotta
2019
The results of the prediction of exposure and seismic vulnerability for the buildings of the historic center of Caltabellotta, obtained with databases of different levels of accuracy, are compared. In particular, the results obtained on the basis of the estimation of the characteristics and of the distribution of the typologies derived from the filling in of the CARTIS sheets on a sector scale are compared with those obtained through a survey from the outside to a building scale. In this latter area, indicators contained in the CARTIS are suitably supplemented with those available in the literature, partly modified to adapt them to the local reality. The vulnerability is evaluated on the ba…
Palermo si cura. Pratiche culturali di mutuo soccorso come risposta alle fragilità della città (post)pandemica
2023
In un quadro di riferimento in cui la crisi è globalizzata ma diseguale e in mancanza di un sistema di welfare capace di rispondere alle urgenze dei contesti e dei gruppi sociali più marginalizzati, una risposta ai nuovi bisogni sociali ed individuali è stata offerta da reti solidali e da pratiche di mobilitazione dal basso che svolgono un ruolo di agency territoriale, spesso indipendentemente o in assenza di Istituzioni. Nel contesto palermitano un impegno agito da una pluralità di soggetti culturali già attivi sul territorio, riuniti in un’assemblea pubblica (Palermo si cura), durante il periodo del primo lockdown hanno dato vita ad azioni di mutuo soccorso per rispondere all’emergenza ec…
BPCO E OSTEOPOROSI
2013
COPD and osteoporosis are frequently associated because they have common risk factors, including age, smoking habits and reduced physical activity. COPD is also characterized by systemic inflammation, malnutrition (up to cachexia), hypovitaminosis D, and the use of local and systemic corticosteroids, all of which could cause deterioration in bone quality with a consequent increase in fragility fractures. These fractures may further impair mobility and increase disability and mortality. The vertebral and rib fractures can directly further affect lung function and promote exacerbations. As a result, the assessment of fracture risk in patients with COPD is of vital importance from the earliest…
IL PAZIENTE ANZIANO CON FRATTURA DI FEMORE: VALUTAZIONE E SUPPORTO NUTRIZIONALE
2013
Osteoporosis in the elderly population is a major health problem worldwide, because it is associated with fragility fractures with consequent financial burden for health systems. Europe and North America are the regions where half of all hip fractures among elderly people occurred today, with Scandinavian countries reporting the highest incidence worldwide. Undernutrition, particularly protein malnutrition, is frequent in elderly with osteoporotic hip fracture, although, the role of dietary protein intake in osteoporosis remains controversial. Poor nutritional status is associated with higher comorbidity indices, mortality and readmissions in patients with femoral fracture. Another crucial …
FC 079HIGH SERUM PHOSPHATE, A NOVEL POTENTIAL RISK FACTOR FOR BONE FRAGILITY FRACTURES IN THE COSMOS STUDY
2021
Abstract Background and Aims Bone fragility fractures (bone fractures) are extremely frequent in haemodialysis (HD) patients. Serum phosphate (P) has been suggested as a risk factor for bone fracture, nonetheless, evidence is poor. The aim of this study was to assess the association between incidence of bone fractures and serum phosphate (P), calcium (Ca) and parathyroid hormone (PTH) in patients from the COSMOS study. Method COSMOS is an observational, prospective, open cohort study with 3 years of follow-up including 6797 haemodialysis patients from 227 centres randomly selected from 20 European countries. At baseline, demographics, comorbidities, treatments, serum biochemical parameters …
Las grandes exposiciones del siglo XXI frente a la fragilidad del territorio
2019
Las exposiciones no son eventos autónomos ni homogéneos, al contrario, su desarrollo constituye la trama de una historia discontinua, el espejo de una sociedad en evolución que experimenta sus reglas y sus paradigmas, mostrándolos a la sociedad. A través de cartografía y bibliografía específica, además de las experiencias personales de los autores, se analizan los eventos de Hannover (2000) que marca el comienzo de las exposiciones del presente siglo, Shanghái (2010), y Milán (2015) para comprender los efectos que los eventos expositivos tienen sobre la transformación de la ciudad y del territorio, en un momento en el cual existe una renovada preocupación sobre el devenir de las ciudades, s…