Showing papers by "Settimio Ferlisi published in 2019"

A multi-scale methodological approach for slow-moving landslide risk mitigation in urban areas, southern Italy

Abstract: Several urban areas in Euro-Mediterranean countries are affected by slow-moving landslides that, even if rarely associated with the loss of human life, can cause damage to structures and infrastructure. In such contexts, the progressive decay of the built environment can bring along a generalized increase of the physical vulnerability and, as a result, slow-moving landslide risk increases over the time. Under these conditions, as long as suitable risk mitigation measures are lacking, the level of risk (also related to earthquakes) could turn out to be no longer acceptable within an a priori unknown time interval. This problem has a relevant social-economic impact, thus requiring the adoption of risk mitigation strategies that need to be effective and, at the same time, sustainable for the involved stakeholders. In this regard, this paper proposes a multi-scale methodological approach—based on the joint use of satellite-derived displacement monitoring data and the results of building damage surveys—whose applicability is tested with reference to urban areas affected by slow-moving landslides in Calabria region (southern Italy).

Damage to Masonry Buildings Interacting with Slow-Moving Landslides: A Numerical Analysis

Abstract: This paper presents the results of a numerical analysis aimed at investigating the response – in terms of damage occurrence and development – of a masonry building undergoing settlements induced by a slow-moving landslide. The analysis is performed by applying the Equivalent Frame Method to a model representative of a low-rise building with shallow foundations located in the historic centre of Lungro town (Calabria region, southern Italy). As a main novelty, data collected by way of both conventional (i.e. inclinometers) and innovative (i.e. DInSAR) monitoring techniques are used to derive the three-dimensional settlement trough to be imposed to the building model’s foundation in the numerical analyses. The obtained outcomes are compared with information gathered from multi-temporal damage surveys to the modeled building. Based on previous studies aimed at typifying the slow-moving landslides, the results obtained could concur to the generation of certain building-foundation-landslide typified models helpful for damage forecasting at the municipal scale.

Multi-parameter Vulnerability Analysis of Settlement-Affected Masonry Buildings with Shallow/Piled Foundations: Case Studies in The Netherlands

Abstract: The paper presents a probabilistic analysis aimed at identifying the most appropriate subsidence related intensity (SRI) parameter (e.g., differential settlement, relative rotation, deflection ratio) that can be used to forecast the severity level of building damage at municipal scale through the generation of empirical fragility and vulnerability curves. The analysis refers to a rich sample of more than seven hundred monitored (by remote sensing techniques) and surveyed masonry buildings – mainly resting with their (shallow or piled) foundations on highly compressible fine-grained “soft soils” – affected by settlements in four urban areas in The Netherlands. The achieved outcomes, once further calibrated and validated, could allow for an improvement of existing geotechnical damage criteria for buildings as well as help local authorities in charge of the management/protection of subsiding urban areas to plan adequate foundation repairing/replacing measures before damage reaches intolerable severity levels.

Probabilistic analysis of vulnerability of buildings to slow moving landslides: a study in two municipalities in southern Italy

Abstract: The paper presents a probabilistic analysis of the vulnerability of buildings interacting with slow-moving landslides. With reference to two municipalities of the Calabria region (southern Italy) severely affected by this type of slope instabilities, the combination of data collected by way of expeditious damage surveys with building settlements retrieved from the use of Differential Interferometry Synthetic Aperture Radar (DInSAR) techniques allows generating separate couples of empirical fragility and vulnerability curves for the two investigated urban areas. The comparison of the obtained results highlights that the use of such tools for damage forecasting purposes in other landslide-affected areas requires selecting – from a statistical point of view – building samples belonging to the same data population (i.e. referring to homogeneous land-urban sys-

Numerical analysis of the behaviour of masonry buildings undergoing differential settlements

Abstract: This paper presents the results of a numerical analysis – carried out by way of the academic version of the TREMURI software implementing the Equivalent Frame Method – that was aimed at generating fragility curves to be associated with existing masonry buildings resting on soils with different mechanical parameters and subjected to differential settlement scenarios. These numerical fragility curves, once validated on the basis of information concerning real cases, could represent a useful tool for decision makers and geotechnical engineers in planning/selecting/designing appropriate foundation repairing/replacing measures aimed at preventing the attainment of intolerable damage severity levels. RÉSUMÉ: Cet article présente les résultats d’une analyse numérique – réalisée à l’aide de la version académique du logiciel TREMURI mettant en œuvre la méthode Equivalent Frame – visant à générer des courbes de fragilité à associer à des bâtiments de maçonnerie existants reposant sur des sols à paramètres mécaniques différents and soumis à des scénarios de tassement différentiel. Ces courbes de fragilité numérique, une fois validées sur la base d’informations concernant des cas réels, pourraient constituer un outil utile pour les décideurs et les ingénieurs géotechniciens dans la planification/sélection/conception de mesures appropriées pour réparer/remplacer les fondations afin d’empêcher l’atteinte des niveaux de gravité des dommages intolérables.