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The seismic stability assessment of anthropogenic cavities is a challenging issue for land and urban planning, particularly in areas of possible interaction with surface structures and infrastructures. The paper proposes a novel methodology for the preliminary assessment at urban scale of the safety level against roof collapse of underground cavities under seismic actions through seismic stability charts, SSCs. The SSCs are the result of extensive parametric two-dimensional FEM analyses focused on cavities excavated in soft rock, as it is frequent in many inhabited areas all over the world. The study is mainly oriented to the instability of shallow cavities, includingthe effects at the ground surface. The SSCs allow evaluation of stability conditions of a generic cavity through a factor of safety, calculated as the minimum ratio between the resistant and loading bending moment of the critical sections of the cavity roof during the whole earthquake duration. The method is applied to the case study of Sant'Agata de' Goti, a historical center in Southern Italy, rising on top of a volcanic tuff ridge. • Methodology to preliminary screen the seismic stability of underground cavities at urban scale. • Parametric 2D FEM analyses to calculate the cavity factor of safety during earthquake. • Analytical interpretation of cavity response under a seismic pseudo-static action. [ABSTRACT FROM AUTHOR]

Italy is one of the countries with the greatest historic heritage in the world, but also one of the most seismic. In this context an earthquake can cause significant damage. Usually, the vulnerability of a building is verified with indepth and expensive structural assessment, without considering spatial relations and local context. In this study a method is proposed for the assessment of Territorial Seismic Vulnerability, based on both building characteristics and morphological and spatial parameters. It is an urban-scale approach that allows an objective classification of buildings using an economical procedure. The method, based on the development of a geographical Multiple Criteria Decision Making model and on the participatory approach of the Analytic Hierarchy Process, has been tested in the study area of Garfagnana (Tuscany). The model can be a useful support tool for urban planning, allowing the optimization of public resources in the most vulnerable areas. [ABSTRACT FROM AUTHOR]

This paper reviews the critical issues of the current urban planning, mobility and accessibility in the post-earthquake (2009) settlement configuration of L’Aquila urban area (Italy), the medieval centre of which has a unique architectural and artistic heritage. The purpose of the study is to analyse the L’Aquila urban planning experiences in order to trace the relationship between the mobility and the spatial structure of the city. The current scenario is considered both as the result of the historical evolution of the settlement and as a dynamic system in which a mix of natural forces, decisional choices and technical expertise have operated. The result of the research is a preliminary proposal for the implementation of the public transportation system that is obtained by integrating a re-designed existing railway line with a sustainable concepts of mobility based on a “dense grid” network. [ABSTRACT FROM AUTHOR]

One of the most important tasks of urban and hazard planning is to mitigate the damages and minimize the costs of the recovery process after catastrophic events. In this context, the capability of urban systems and communities to recover from disasters is referred to as resilience. Despite the problem of resilience quantification having received a lot of attention, a mathematical definition of the resilience of an urban community, which takes into account the social aspects of an urban environment, has not yet been identified. In this article, we provide and test a methodology for the assessment of urban resilience to catastrophic events which aims at bridging the gap between the engineering and the ecosystem approaches to resilience. We propose to model an urban system by means of different hybrid social-physical complex networks, obtained by enriching the urban street network with additional information about the social and physical constituents of a city, namely citizens, residential buildings, and services. Then, we introduce a class of efficiency measures on these hybrid networks, inspired by the definition of global efficiency given in complex network theory, and we show that these measures can be effectively used to quantify the resilience of an urban system, by comparing their respective values before and after a catastrophic event and during the reconstruction process. As a case study, we consider simulated earthquakes in the city of Acerra, Italy, and we use these efficiency measures to compare the ability of different reconstruction strategies in restoring the original performance of the urban system. [ABSTRACT FROM AUTHOR]

The city-center of L'Aquila suffered big damages from the main seismic event (6th April 2009, 3:32 a.m., local time; Ml=5.8, Mw= 6.2) of the seismic sequence that included hundreds of aftershocks (more than 30 of them 3.5

Remote Sensing (RS) data and techniques, in combination with GIS and landscape metrics, are fundamental to analyse and characterise Land Cover (LC) and its changes. The case study here described, has been conducted in the area of Avellino (Southern Italy). To characterise the dynamics of changes during a fifty year period (1954/2004), a multi-temporal set of images has been processed: aerial photos (1954), and Landsat scenes (MSS 1975, TM 1985 and 1993, ETM+ 2004). LC pattern and its changes are linked to both natural and social processes whose driving role has been clearly demonstrated in the case study: after the disastrous Irpinia earthquake (1980), specific zoning laws and urban plans have significantly addressed landscape changes. [ABSTRACT FROM AUTHOR]

This paper aims to present, through a photographic reportage, the current state of rebuilding of the most devastated villages by the earthquake that hit the Southern Italy on 23 November 1980, in Irpinia-Basilicata. The earthquake was characterized by magnitude Ml = 6.9 and epicentral intensity I0 = X MCS. It was felt throughout Italy with the epicenter in the Southern Apennines, between the regions of Campania and Basilicata that were the most damaged areas. About 800 localities were serious damaged; 7,500 houses were completely destroyed and 27,500 seriously damaged. The photographic survey has been done in 23 towns during the last five years: Castelnuovo di Conza, Conza della Campania, Laviano, Lioni, Santomenna, Sant'Angelo dei Lombardi, Balvano, Caposele, Calabritto and the hamlet of Quaglietta, San Mango sul Calore, San Michele di Serino, Pescopagano, Guardia dei Lombardi, Torella dei Lombardi, Colliano, Romagnano al Monte, Salvitelle, Senerchia, Teora, Bisaccia, Calitri and Avellino. Forty years after the 1980 earthquake, the photographs show villages almost completely rebuilt with modern techniques where reinforced concrete prevails. Only in few instances, the reconstruction was carried out trying to recover the pre-existing building heritage, without changing the original urban planning, or modifying it. We argue that this photography collection allows to assess the real understanding of the geological information for urban planning after a major destructive seismic event. Even more than this, documenting the rebuilding process in a large epicentral area reveals the human legacy to the natural landscape, and our ability, or failure, to properly interpret the environmental fate of a site. [ABSTRACT FROM AUTHOR]