Alessandro Rasulo

Seismic safety of network structures and infrastructures

Realistic assessment of network structural safety requires modelling of a reasonably large part of the network itself. Although this statement may appear too demanding, both for modelling and computing reasons, there are clear motivations and technological possibilities to do complex network analyses. In this paper, the safety analyses of three infrastructures that have been shaken by an earthquake are described, modelled and computed: the electric power, water and road systems. For each network, results extracted from real networks, some of which have been studied in the past by the authors, are presented and discussed. No inter-network analysis is carried out, although it is recognised that this would be the most complete approach. The common parts in the procedure to model and analyse each network, via Monte Carlo simulations, are detailed at the beginning of the paper, thus showing the many common points that show up in any network analysis.

Performance of Lifelines During the 2002 Molise, Italy, Earthquake

The Molise earthquake affected a wide rural area with sparse houses, villages and towns. The paper investigates the response of water, electric power, telecommunications, natural gas, rail and motorway systems. Despite the amount of damage to buildings, lifeline systems reported only minor damage. The damage was light not only because the event caused relatively moderate ground motion in the affected area but also because the main lifelines do not cross the epicentral region and were in a fair state of maintenance.

Seismic Risk Analysis at Urban Scale in Italy

Seismic risk maps are a useful tool researchers use for representing to stakeholder and decision makers the adverse outcomes a seismic event can have over the territory. Generally, in those studies, urban areas, where the human activities are concentrated, focuses major attention. Main concerns are about the existing building stock, mostly composed by structures not compliant with modern seismic design criteria. The production of a seismic risk map is a complex task that involves the combination of data coming from different field of expertise. The aim of the study is to show how the already available information can be combined together in a Geographical Information System (GIS) tool. The results provide a reliable representation of the seismic risk at urban scale to be used when planning the mitigation measures to be undertaken in order to improve the level of preparedness in case of an earthquake. The analysis has been applied for demonstration purposes to the town of Cassino, Central Italy.

Experimental Response of RC Beams Strengthened in Shear by FRP Sheets

The paper discusses the results of an experimental investigation carried out on reinforced concrete (RC) beams strengthened in shear by externally bonded fiber reinforced plastic (FRP) sheets. The study is devoted to analyze the role that the transverse steel reinforcement and the beam slenderness ratio could play on the resistant mechanism of RC beams strengthened in shear by FRP composites. The results are summarized and analyzed in detail in the paper in terms of shear capacity, cracking pattern and shear resisting contribution of FRP.

A Seismic Risk Model for Italy

All Italian territory, with the only exception of the island of Sardinia, is subject to seismic events, making this threat a major concern for decision makers in charge for the implementation of risk reduction policies. Seismic risk vary greatly across the country and within single administrative regions. Seismic risk maps at national scale are therefore a useful tool for representing the expected adverse outcomes due to the seismic events and for programming the appropriate mitigation measures. The production of those maps is a complex task that involves the combination of data coming from different field of expertise. The aim of the study is to show how the already available information can be combined together in a Geographical Information System (GIS) tool. The results provide a reliable representation of the seismic risk at national scale to be used when planning the mitigation measures to be undertaken in order to improve the level of preparedness in case of an earthquake.

A Frame Element Model for the Nonlinear Analysis of FRP-Strengthened Masonry Panels Subjected to In-Plane Loads

A frame element model for evaluating the nonlinear response of unstrengthened and FRP-strengthened masonry panels subjected to in-plane vertical and lateral loads is presented. The proposed model, based on some assumptions concerning the constitutive behaviour of masonry and FRP material, considers the panel discretized in frame elements with geometrical and mechanical properties derived on the basis of the different states characterizing the sectional behaviour. The reliability of the proposed model is assessed by considering some experimental cases deduced from the literature.

Geostatistical Analysis of Settlements Induced by Groundwater Extraction

One of the most important effects induced by the over-exploitation of aquifers is the land subsidence. This dangerous situation may reduce in relatively short time the functionality and safety of structures and infrastructures present on a territory and impair their efficiency and stability. The city of Bologna is one of the most sensational cases of Italy, especially for the amount of recorded settlements and the great historical and cultural value of exposed assets. This article analyses the spatial and temporal distribution of settlements over an area of about 270 km2 including the centre of the city. The topographical measurements, carried out starting from 1943 with a progressively increasing detail, highlight an articulated framework of settlements with maximum values exceeding 4 m. After a brief introduction of the phenomenon and its causes, a geostatistical analysis has been performed on a Geographical Information System. In order to validate the results, the potential damage on buildings present in the area has been evaluated. To this end, data were collected regarding the geometrical characteristics and the structural types of the buildings. The strain levels from the current configuration of the ground surface have been calculated for each of them. Finally, the expected damage levels have been assessed, following the classifications proposed in the literature that allow to assign a severity level for each building. These results were compared with damage observed by previous studies. This approach is a prerequisite to the planning of any vulnerability mitigation strategy.