A fuzzy methodology to evaluate the landslide risk in road lifelines

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finite element modelling of unpaved road reinforced with geosynthetics

Abstract The technique of soil mechanical stabilization, using geosynthetics, is extensively used in the construction of unpaved roads with a low volume of traffic. Unpaved roads consist of unbound granular bases overlying cohesive subgrades. When built on weak subgrades, these roads are subject to problems like excessive rutting and mud-pumping, increasing maintenance costs and usually leading to periodic interruptions to traffic. Particularly, the field applications of geosynthetic reinforcement placed above a weak subgrade can markedly improve the performance of these roads decreasing permanent vertical deformations, increasing lateral restraint ability, which results in increased pavement service life or reduced base thickness to carry the same number of load repetitions. This paper focuses on providing a numerical investigation using a bi-dimensional Finite Element Method (FEM), using ABAQUS software, to analyze the improvement of reinforced unpaved road under repeated wheel traffic load conditions in terms of aggregate base course thickness saving

MAPPA DELLA SUSCETTIBILITA’ FRANA MEDIANTE UTILIZZO DELLA LOGICA FUZZY

The present paper proposes a new methodology to characterize the landslide susceptibility of Reggio Calabria territory. The values obtained were classified into five categories: very low, low, medium, high and very high, and were than exported into GIS environment to produce a landslide susceptibility map. The principal objective of the proposed study is to identify the sections of the road network exposed to landslide hazards starting from the susceptibility map. To this aim, a fuzzy system was designed with 2 input, 15 rules “if-then” and 1 output representing the “level of attention” for the considered transport infrastructure, being a higher value of attention level correspondent to a higher landslide hazard. From the obtained results it is possible to notice that the most relevant roads in terms of connection, as the highway A3, the road SS106 and other roads linking the Ionian Coast to the Tirrenic Coast, are those displaying the highest level of attention.  DOI: http://dx.medra.org/10.19254/LaborEst.13.0

MAPPA DELLA SUSCETTIBILITA’ FRANA MEDIANTE UTILIZZO DELLA LOGICA FUZZY

The present paper proposes a new methodology to characterize the landslide susceptibility of Reggio Calabria territory. The values obtained were classified into five categories: very low, low, medium, high and very high, and were than exported into GIS environment to produce a landslide susceptibility map. The principal objective of the proposed study is to identify the sections of the road network exposed to landslide hazards starting from the susceptibility map. To this aim, a fuzzy system was designed with 2 input, 15 rules “if-then” and 1 output representing the “level of attention” for the considered transport infrastructure, being a higher value of attention level correspondent to a higher landslide hazard. From the obtained results it is possible to notice that the most relevant roads in terms of connection, as the highway A3, the road SS106 and other roads linking the Ionian Coast to the Tirrenic Coast, are those displaying the highest level of attention.  DOI: http://dx.medra.org/10.19254/LaborEst.13.0

DRONI PER LA MODELLAZIONE 3D E PER L’INDIVIDUAZIONE DEGLI AMMALORAMENTI NELLE PAVIMENTAZIONI STRADALI

The deteriorations of road infrastructure, that is, the loss of initial performance in the aftermath of vehicular traffic, both in the assessment of functional status and in natural agents (frost-thaw, earthquake, salty, etc.) has led to the need for development of non-destructive tests designed to provide useful elements without damaging the work. Pavement damages are one of the major causes of road accidents. In view of this criticality, it is necessary to devise an effective pavement maintenance management system with respect to economic constraints with the aim of ensuring adequate standards. Certainly an careful visual analysis is the basis for a correct evaluation of the conditions of the work being observed. In this respect, this note deals with a system for the production of 3D models based on the acquisition of digital images, by means of an automatic flight drone, applied to the analysis of a road infrastructure located in the territory of the Province of Reggio Calabria. Later processing of images was carried out via commercial software, based on special Structure from Motion (SfM) techniques. The SfM is a significant advance in the field of both aerospace and terrain, with results, timing and quality, comparable to those obtainable through more traditional data acquisition methods.DOI: http://dx.medra.org/10.19254/LaborEst.15.0

DRONI PER LA MODELLAZIONE 3D E PER L’INDIVIDUAZIONE DEGLI AMMALORAMENTI NELLE PAVIMENTAZIONI STRADALI

The deteriorations of road infrastructure, that is, the loss of initial performance in the aftermath of vehicular traffic, both in the assessment of functional status and in natural agents (frost-thaw, earthquake, salty, etc.) has led to the need for development of non-destructive tests designed to provide useful elements without damaging the work. Pavement damages are one of the major causes of road accidents. In view of this criticality, it is necessary to devise an effective pavement maintenance management system with respect to economic constraints with the aim of ensuring adequate standards. Certainly an careful visual analysis is the basis for a correct evaluation of the conditions of the work being observed. In this respect, this note deals with a system for the production of 3D models based on the acquisition of digital images, by means of an automatic flight drone, applied to the analysis of a road infrastructure located in the territory of the Province of Reggio Calabria. Later processing of images was carried out via commercial software, based on special Structure from Motion (SfM) techniques. The SfM is a significant advance in the field of both aerospace and terrain, with results, timing and quality, comparable to those obtainable through more traditional data acquisition methods

Stanja Jπ = 2+ i 0+, T = 0 8Be na energijama pobuđenja oko 20 MeV

The 7Li(d, αα)n reaction induced by deuterons of an incident energy of 7 MeV has been used to excite the 8Be nucleus in the region of excitation energy Ex of about 20 MeV. Each of the obtained αα coincidence spectra was fitted by an incoherent sum of the Jπ=2+ and 0+, T=0 8Be levels at Ex=20.1 and 20.2 MeV, respectively. The results show that the experimental data are well fitted when the G values deduced for these levels are 0.90 and 0.70 MeV, respectively.Reakcija 7Li (d, αα) n inducirana deuteronima energije 7 MeV je iskorištena za proučavanje jezgre 8Be na energijama pobuđenja Ex oko 20 MeV. Koincidentni αα spektri poravnani su nekoherentnim zbrojem stanja Jπ = 2 + na Ex = 20, 1 MeV i Jπ = 0+ na Ex = 20,2 MeV. Rezultati pokazuju da su eksperimentalni podaci najbolje opisani ako se za širine navedenih stanja uzmu vrijednosti 0,90 MeV odnosno 0, 70 Me V

Stanja Jπ = 2+ i 0+, T = 0 8Be na energijama pobuđenja oko 20 MeV

The 7Li(d, αα)n reaction induced by deuterons of an incident energy of 7 MeV has been used to excite the 8Be nucleus in the region of excitation energy Ex of about 20 MeV. Each of the obtained αα coincidence spectra was fitted by an incoherent sum of the Jπ=2+ and 0+, T=0 8Be levels at Ex=20.1 and 20.2 MeV, respectively. The results show that the experimental data are well fitted when the G values deduced for these levels are 0.90 and 0.70 MeV, respectively.Reakcija 7Li (d, αα) n inducirana deuteronima energije 7 MeV je iskorištena za proučavanje jezgre 8Be na energijama pobuđenja Ex oko 20 MeV. Koincidentni αα spektri poravnani su nekoherentnim zbrojem stanja Jπ = 2 + na Ex = 20, 1 MeV i Jπ = 0+ na Ex = 20,2 MeV. Rezultati pokazuju da su eksperimentalni podaci najbolje opisani ako se za širine navedenih stanja uzmu vrijednosti 0,90 MeV odnosno 0, 70 Me V

3D Finite element model of a blast load in a tunnel

This paper presents a 3D finite element analysis of the effect caused by a blast inside a reinforced concrete tunnel. The simulated explosion was caused by the crash of a heavy vehicle transporting inflammable material (LPG). The finite element technique was used to analyze the structural problems on the tunnel reinforced concrete structure considering the fire action and the subsequent explosion (blast) effect, incorporating appropriate material models. Through FEM software the tunnel behavior was described with regard to structural safety. Indeed, tunnels must be designed to withstand damage factors, so it is desirable that if such an explosion did occur, the tunnel should be able to return to service in safety as soon as possible with minor repairs. Therefore, following the presented analysis, the most important factors influencing the dynamic response and the damage of the structure could be identified. The simulation involved aspects of thermal analysis and structural problems and the tensions in the structure generated by the effect of temperature caused by the fire and by the blast overpressure were analyzed. Following this approach, the most important factors influencing the dynamic response and damage of structure can be identified and appropriate preventive measures can be designated

Finite Element Modelling of Unpaved Road Reinforced with Geosynthetics

Abstract The technique of soil mechanical stabilization, using geosynthetics, is extensively used in the construction of unpaved roads with a low volume of traffic. Unpaved roads consist of unbound granular bases overlying cohesive subgrades. When built on weak subgrades, these roads are subject to problems like excessive rutting and mud-pumping, increasing maintenance costs and usually leading to periodic interruptions to traffic. Particularly, the field applications of geosynthetic reinforcement placed above a weak subgrade can markedly improve the performance of these roads decreasing permanent vertical deformations, increasing lateral restraint ability, which results in increased pavement service life or reduced base thickness to carry the same number of load repetitions. This paper focuses on providing a numerical investigation using a bi-dimensional Finite Element Method (FEM), using ABAQUS software, to analyze the improvement of reinforced unpaved road under repeated wheel traffic load conditions in terms of aggregate base course thickness saving