Francis Cirianni

Dynamic Behavior of Granular Mixture Solids

In this paper a theoretical and numerical study of impulsive loads over a granular medium free surface has been developed. We will model a real case, as a high deformable solid impacting a less deformable surface, and consequently subject to micro and macro medium failure. Developing a macroscopic approach we resolve the macro-stress in the homogenized two-dimensional medium and subsequently apply a representative volume element (RVE) analysis modeling to the micro-scale. The problem is developed by energetic approach on an elasto-plastic element using an energy functional containing bulk and surface contributions. Finally, a numerical application is presented.

A Methodology for Assessing the Seismic Vulnerability of Highway Systems

Modern society is totally dependent on a complex and articulated infrastructure network of vital importance for the existence of the urban settlements scattered on the territory. On these infrastructure systems, usually indicated with the term lifelines, are entrusted numerous services and indispensable functions of the normal urban and human activity.The systems of the lifelines represent an essential element in all the urbanised areas which are subject to seismic risk. It is important that, in these zones, they are planned according to opportune criteria based on two fundamental assumptions: a) determination of the best territorial localization, avoiding, within limits, the places of higher dangerousness; b) application of constructive technologies finalized to the reduction of the vulnerability.Therefore it is indispensable that in any modern process of seismic risk assessment the study of the networks is taken in the rightful consideration, to be integrated with the traditional analyses of the buildin...

Mitigation of Railway Traffic Induced Vibrations: The Influence of Barriers in Elastic Half-Space

In this paper, the problem of vibrations induced by trains and their propagation through the soil is studied. Particular attention is focused on the vibration induced by trains in motion and on the effects of such vibrations on the foundations of buildings in proximity of the tracks. The interaction between propagating waves induced by trains in motion and buildings foundations is a problem which does not admit a straightforward analytical solution; thus a solution is given by the use of a model based on the finite elements method. Firstly, we analyze the theoretical aspects of the problem by considering constant or harmonic loads moving along a straight railway track; then, we define a transfer function soil-railway and the response function of the entire system. The study aims to address the wave propagation in an elastic semi-space and the presence in the ground of a discontinuity element, such as a barrier of a given depth is considered. The efficiency variation of barriers is analyzed in function of the different materials used, and different numerical simulations are analyzed in order to study how the wave propagation and the track-soil interaction are influenced by the membrane, seen as damping barrier.

Analysis of Transport Modes in the Urban Environment: an Application for a Sustainable Mobility System

This paper analyzes transport modes in the urban environment and the paper confronts the experience in different settings, urban and suburban, in cities of different sizes. The process introduced aims to improve the quality of life and access for more sustainable patterns of development, while at the same time not harming the urban mobility, proposing a model that can be applied to the different urban areas. The high costs of construction of additional road space, and the consideration that a greater offer of road space is an impulse for a greater demand of private car traffic, leads the planning process in the direction of using existing road space more efficiently, by using traffic control mechanisms, and shifting demand to alternative modes. The spreading of heavy traffic using unsuitable roads has led to the increase of the risks for public health and safety, being the levels of pollution to be dangerously high and the pedestrian mobility to be strongly restricted. The actions discussed in the paper are parking policies, which aim to redistribute on and off road parking, discouraging parking in what is the central area by means of charging policies and the institution of Controlled Traffic Zones, and by doing so shifting long term parking to fringe areas. A key factor of the success of the proposed parking policy is the institution of pedestrian routes promoting walking and cycling. The planning of the Transport System includes a mix of measures designed to encourage people to use public transport (“pull” measures) and, where appropriate, measures to reduce the use of private cars (“push” measures). Push-measures can be divided into financial instruments, and technical and regulatory constraints. In the paper an application to study areas is presented, describing the scenario before the adoption of the proposed policies, and after the application at the date, presenting some results in comparison. The government of cities requires a policy for traffic management, and thus it implies, among the other traffic control strategies, adequate parking policies. Traffic and transport related activities and infrastructures can affect users and non users of the system alike, as in the case of the occupation of public spaces, accidents, noise and air pollution, and congestion of the road network (i.e. transport externalities).

A Review Methodology of Sustainable Urban Mobility Plans: Objectives and Actions to Promote Cycling and Pedestrian Mobility

In the previous decade, the European Commission, among its policies to increase sustainability and the quality of life in European cities, has introduced the Sustainable Urban Mobility Plan (SUMP). The concepts brought forward in this novel planning approach further focus on sustainable transport modes, such as cycling and pedestrian mobility, which are two of the main issues included in SUMP. The European challenge is to integrate long-term planning perspectives and short-term actions. In this context, the aim of this paper is to analyze and classify the objectives and actions proposed in the SUMP adopted by European cities, focusing on the policies for improving cycling and pedestrian mobility. Therefore a review methodology is proposed in order to verify their coherence with the European guidelines, classifying objectives and actions for the promotion of cycling and pedestrian mobility. The research required that each of a set of SUMPs, adopted by various European cities, be analyzed and classified in order to identify the objectives and the planned actions and to verify the presence of qualitative and quantitative indicators, therefore presenting a first application of the proposed methodology. The results show how the cities follow the European policies relative to urban mobility in terms of objectives and actions and, in particular, in relation to cycling and pedestrian mobility. All cities in the sample set goals to improve safety for pedestrians and cyclists by means of: the modernization and adaptation of the existing cycling paths and pedestrian walkways; and the construction of new long-distance cycle paths and of new pedestrian walkways and public areas that are comfortable for pedestrians. This work can be useful in order to verify the implementation of the sustainable urban planning process, establishing a benchmark process useful for other cities to follow.