Optimization of the Mix-Design System for the Sub-ballast Railroad

2017

Bituminous sub-ballast is an alternative solution to the unbound granular sub-ballast used in the railway track due to several benefits that it can provide. Indeed, it contributes to maintain the moisture content in the subgrade unchanged during all year. This decreases the subgrade deterioration process. Moreover, the presence of bituminous sub-ballast can also reduce vertical stiffness variations on the track; it can have a positive effect in the maintenance needs at transition sections (bridge-embankment) and in the attenuation of the vibrations induced by the rail traffic. Despite the importance of the presence of the bituminous sub-ballast to conceive the construction and/or rehabilita…

VIRTUAL REALITY AND BIM FOR INFRASTRUCTURES

2023

Abstract. Building Information Modelling (BIM) has been widely adopted in the construction industry as a means of improving project efficiency, reducing errors, and facilitating collaboration among stakeholders. However, its potential for the infrastructure sector has not been fully explored. Infrastructure projects, such as roads, bridges, tunnels, and airports, are often complex and require the integration of multiple systems and disciplines. BIM has the potential to provide a digital representation of the infrastructure project, allowing for improved design, construction, and maintenance. This paper aims to explore the potential benefits of BIM in the infrastructure sector, examine the c…

THE RESISTANCE TO FATIGUE OF DRY ASPHALT RUBBER CONCRETE FOR SUB-BALLAST LAYER

2015

The more and more frequent use of recycled materials within the road and railway infrastructures is now an irreversible trend. In this area the use of Dry Asphalt Rubber Concrete (DARC) in sub-ballast layer seems to be a suitable technique to reach high mechanical and environmental performance even if such material should be analyzed over a long time horizon. This paper presents the results of experimental research focused on the resistance to fatigue of Dry Asphalt Rubber Concrete in sub-ballast layers; the survey has been carried out using four-point bending test (4pbt) on mixture samples with different rubber contents. The results of fatigue in DARC have been compared with the performanc…

Investigating the Multi-Recyclability of Recycled Plastic-Modified Asphalt Mixtures

2023

Although the benefits of asphalt recycling have been scientifically proven and several best practices are being implemented, further research is required in specific and specialized areas. One of these circumstances is the recycling of Reclaimed Asphalt Pavements (RAPs) that contain asphalt modifiers such as elastomers and/or plastomers. Following the principles of the circular economy and considering the sustainability implications of asphalt mixtures, this paper deals with the multi-recyclability of asphalt mixtures containing 50% RAP with and without a recycled plastic asphalt modifier and rejuvenating agent. The recycled plastic asphalt modifier was made of hard recycled plastics and wa…

European National Road Authorities and Circular Economy: An Insight into Their Approaches

2020

The pavement engineering industry, having realized the significance of the impacts that it imposes on the environment through the production, construction and management of its products and assets, has been driven towards a more sustainable and circular way of operating. This has partly been through asphalt recycling, which is an area that many road authorities have prioritized. However, not all the National Road Authorities (NRAs) and/or sector stakeholders seem to be adequately familiar with the Circular Economy (CE) concept. This paper attempts to assist the transition of NRAs to a more circular way of doing business, by analyzing the current situation of CE within national/regional auth…

A Top-Down Approach Based on the Circularity Potential to Increase the Use of Reclaimed Asphalt

2023

Resource depletion and climate change, amongst others, are increasingly worrying environmental challenges for which the road engineering sector is a major contributor. Globally, viable solutions that comply with the principles of circular economy (CE) are being investigated that can replace conventional asphalt mixtures in a post-fossil fuel society. The use of reclaimed asphalt (RA) is a widely used and well-established method to reduce the environmental and economic impacts of asphalt mixtures while increasing their circularity. However, RA’s market supply and demand have not yet been systematically analyzed and established. Moreover, the actual circularity potential and the opportu…

Towards a new mix design method for asphalt mixtures containing rap

2016

Recycling is one of the most important aspects to conceive the new construction or rehabilitation of sustainable road infrastructures. Even if Reclaimed Asphalt Pavement (RAP) is commonly used in the practice, its presence may lead to some critical aspects due to the physical and chemical phenomena occurring during the new mix process. For instance, the formation of RAP clusters during a new mix may inhibit the uniform distribution of the virgin binder as well as cause changes in the design grading curve of the mixture. Indeed, laboratory results demonstrate that small-size RAP particles stick together forming clusters. The amount of clusters depends on different parameters observed: The pe…

Exploiting 3D Modelling and Life Cycle Assessment to Improve the Sustainability of Pavement Management

2020

Today road agencies worldwide face difficult decisions for construction, maintenance and rehabilitation of their road infrastructure as they try to balance limited budgets. This is further complicated rising environmental concerns over equipment and techniques used for these practices. This has led agencies to consider alternative approaches for smarter and sustainable pavement asset management systems. This paper considers the use of a low-cost 3D image modelling distress identification and classification proposal for data acquisition and analysis. To establish its environmental friendliness, a case study in Palermo, Italy, is considered wherein a Life Cycle Assessment (LCA) exercise is do…

Examining the critical factors that influence the success of construction and demolition waste reverse logistics operations

2022

The reverse logistics (RL) performance of construction and demolition waste (C&DW) differs significantly between countries. Although some countries are successfully circular, other countries are still far behind; with C&DW being largely directed to landfills or being illegally dumped. There is a lack of guidelines on the requirements for transitioning countries towards C&DW diversion, and little attention has been given to the factors that influence the success of C&DW RL and increased circularity. This study aims to develop a framework that helps in structuring and assessing the success of C&DW RL on a regional level and serves as a guide for transitioning developing co…

Image-based 3D reconstruction using traditional and UAV datasets for analysis of road pavement distress

2018

Abstract On local and urban networks, the enduring issue of scarce resources for Maintenance, Rehabilitation, and Reconstruction strategies (MR&R) has led, in many cases, to using unadjusted or poor techniques for road pavement distress detection and analysis, yielding ineffective or even counterproductive results. Therefore, it is necessary to have tools that can carry out quick, reliable and low-cost assessment surveys. This paper aims at validating the use of innovative and low-cost technologies for road pavement analysis, assessing their potentialities for improving the automation and reliability of distress detection. A Structure from Motion (SfM) technique is analyzed at different alt…

Exploiting Data Analytics and Deep Learning Systems to Support Pavement Maintenance Decisions

2021

Road networks are critical infrastructures within any region and it is imperative to maintain their conditions for safe and effective movement of goods and services. Road Management, therefore, plays a key role to ensure consistent efficient operation. However, significant resources are required to perform necessary maintenance activities to achieve and maintain high levels of service. Pavement maintenance can typically be very expensive and decisions are needed concerning planning and prioritizing interventions. Data are key towards enabling adequate maintenance planning but in many instances, there is limited available information especially in small or under-resourced urban road authorit…

Assessing the Open Trenches in Screening Railway Ground-Borne Vibrations by Means of Artificial Neural Network

2009

Reducing ground borne vibrations in urban areas is a very challenging task in railway transportation. Many mitigation measures can be considered and applied; among these open trenches are very effective. This paper deals with the study of the effect, in terms of reduction of vertical and horizontal displacements and velocities, of the open trenches. 2D FEM simulations have been performed and several open trench configurations have been analysed varying the main geometric features such as width and depth, distance from the rail, thickness of the soil layer over the rigid bedrock, type of the ground, ratio between the depth of the trench, and the thickness of the soil layer. For quantifying t…

Using UAV Based 3D Modelling to Provide Smart Monitoring of Road Pavement Conditions

2020

Road pavements need adequate maintenance to ensure that their conditions are kept in a good state throughout their lifespans. For this to be possible, authorities need efficient and effective databases in place, which have up to date and relevant road condition information. However, obtaining this information can be very difficult and costly and for smart city applications, it is vital. Currently, many authorities make maintenance decisions by assuming road conditions, which leads to poor maintenance plans and strategies. This study explores a pathway to obtain key information on a roadway utilizing drone imagery to replicate the roadway as a 3D model. The study validates this by using stru…

Experimental Survey on Dry Asphalt Rubber Concrete for Sub-ballast Layers

2012

This paper presents the results of an experimental survey on the potential application of DARC (dry asphalt rubber concrete) in rail superstructure, within sub-ballast layers by measuring its damping and mechanical properties. Based on the environmental friendly point of view the DARC has the significant advantage as the backfill material of sub-ballast layer because the rubber comes from the waste tires of truck and its usage can results a significant recycling of non-biodegradable wastes. After a preliminary mix-design of several DARCs, with different rubber content that confirmed by using the Marshall test, the stiffness modulus and damping ratio both of a standard bituminous mixture and…

ISIM - INFRASTRUCTURES & STRUCTURES INFORMATION MODELING: A NEW CONCEPT OF BIM FOR INFRASTRUCTURES

2023

The application of Building Information Modeling (BIM) in infrastructure and structural projects, known as Integrated Structural and Infrastructure Modeling (ISIM), has gained attention in recent years due to its potential to revolutionize the construction industry. By providing a digital representation of the built environment, BIM allows for improved collaboration and communication between project stakeholders, leading to enhanced project outcomes. The ISIM approach is centered on the creation of a digital twin, a three-dimensional model of the infrastructure or structure, which serves as a virtual replica of the physical asset. This digital twin provides a platform for analysis, decision…

Performance of asphalt mixes with high recycling rates for wearing layers

2016

The corresponding paper presents selected results of a research on the feasibility of going toward 100% recycling of asphalt pavements into surface courses through an increasing percentage of RA within the mixes. The research is carried out within a two-year CEDR Transnational Road Research project, AllBack2Pave, led by the Technische Universitaet Dresden (Germany), together with the University of Nottingham (UK) and the University of Palermo (Italy), and finalised in January 2016. The main objectives of the project are - to establish, through laboratory tests on binders and asphalt mixes, whether the use of high rates of RA is feasible in developing mixes with high level of durability, and…

Increased Stability of Rubber-Modified Asphalt Mixtures to Swelling, Expansion and Rebound Effect during Post-Compaction

2017

The application of bituminous mixtures modified with rubber from scrap-tires require attention and care during mixing and compaction. Rubber modifies the properties because it reacts in the internal structure of bitumen at high temperatures changing the performance of the mixture (interaction process of solvents with binder-rubber aggregate). The main change is the increasing of the viscosity and elasticity of the binder due to the larger sizes of the rubber particles by dry process but, this positive effect is counteracted by short mixing times, compared to wet technology, and due to the transport processes, curing time and post-compaction of the mixtures. Therefore, negative effects as sw…

Prediction of hydraulic and acoustic properties of open-graded mixes

2014

The use of open-graded mixes increases significantly the hydraulic permeability of pavement and contributes to reduce the noise impact in comparison to traditional pavement. Such characteristics are very appealing and would greatly increase driver's safety. However, during service life, the pores tend to be clogged by many factors among them secondary traffic compaction and filling of voids by fine materials are relevant, especially on heavy routes. In this case the noise reduction and drainage capabilities will gradually disappear, causing serious problems for road safety and maintenance. In this paper we propose a simulation approach in order to predict the drainage and acoustic behavior …

The Sustainability of Reclaimed Asphalt as a Resource for Road Pavement Management through a Circular Economic Model

2019

The transition of the road engineering industry to a circular way of doing business requires more efficient and sustainable resources, energy, and waste management. The rates in which reclaimed asphalt is being recycled or reused in the asphalt mixture production process constitutes a crucial parameter in this transition. This paper aims at establishing a further step towards the combined circularity and sustainability of asphalt pavements, by introducing a framework for quantifying their Material Circularity Index. The framework is based on the methodology proposed by the Ellen MacArthur Foundation and accordingly tailored for the context of asphalt pavements. This study, thus, attempts to…

Integrating Circularity in the Sustainability Assessment of Asphalt Mixtures

2020

Rising concerns about the impacts that the road engineering industry is imposing to the environment have redirected national road authorities to firmly re-consider the sustainability implications of their operations. Lately, though, sustainability has established a forceful correlation with the Circular Economy and its principles. The road engineering industry, therefore, is moving towards more circular approaches. However, this is occurring without the assessment of the potential impacts of such a transition. For this reason, in this study, a composite indicator, namely, Environmental Sustainability and Circularity indicator (ESCi), for investigating the potential effects that increased ci…

Optimization and sensitivity analysis of existing deep learning models for pavement surface monitoring using low-quality images

2022

Automated pavement distress detection systems have become increasingly sought after by road agencies to in crease the efficiency of field surveys and reduce the likelihood of insufficient road condition data. However, many modern approaches are developed without practical testing using real-world scenarios. This paper ad dresses this by practically analyzing Deep Learning models to detect pavement distresses using French Secondary road surface images, given the issues of limited available road condition data in those networks. The study specifically explores several experimental and sensitivity-testing strategies using augmentation and hyper- parameter case studies to bolster practical mode…

Developing a framework for using structure-from-motion techniques for road distress applications

2020

On Urban road networks, road agencies need to quickly identify road pavement distresses in order to identify appropriate maintenance and rehabilitation strategies. This is integral as agencies are plagued with financial and time constraint issues. There have been several attempts over the last few years to identify new solutions and techniques to solve these issues. Several of these have shown merit and accuracy in identifying distresses. However, the techniques in many instances are not correlated to available distress identification standards. One of the considered techniques is the use of Structure-from-Motion, which tries to recreate 3D distress models for identification and analysis. T…

Procedure for a Temperature-Traffic Model on Rubberized Asphalt Layers for Roads and Railways

2017

The impact of temperature on the mechanical properties and thermal susceptibility of the railway bituminous sub-ballast layer, has served as motivation to develop the advanced measurement of thermal cycles in this layer and, an evaluation of the average seasonal temperatures interpolated by sinusoidal functions, of which characteristic parameters are determined. According to weather situation, Barber’s temperature model was used to prove the effectiveness for the railway superstructure. It is included the assessment of improved modified asphalt mixes performed with coarse rubber from scrap tires, having 1.5 to 3 percent of crumb rubber (particle size 0.2-4 mm) by weight of the total mix, as…

Mobile Mapping System: case study of the Messina-Palermo motorway layout

2009

This paper presents the first results of the MMS (Mobile Mapping System) survey on the geometry of the A20 italian motorway Messina-Palermo. The layout parameters are the essential data for an effective management of a single or a road network. In particular these parameters are essential for applying the Design Consistency methodology to proposed or existing road infrastructures; through this methodology the road manager can make sure that the road characteristics are adjusted to the driving behaviour of motorists by analysing the relationship between horizontal and vertical alignment and the design and operating speed. Both the difficult finding of the road design schemes, particularly in…

A FEM model of rail track-ground system to calculate the ground borne vibrations: A case of rail track with wooden sleepers and k-fastenings at Caste…

2007

The prediction of ground borne vibrations is an important issue that needs a multidisciplinary research approach. The principal topics concern both the interaction between train and rail and the interaction between rail track and ground.

A dissipated energy comparison to evaluate fatigue resistance using 2PB

2012

Flexural fatigue due to repeated traffic loading is a process of cumulative damage and one of the main failure modes of flexible pavement structures. Typically, micro-cracks originate at the bottom of an asphalt concrete layer due to horizontal tensile strains. Micro-cracking starts to propagate towards the upper layers under repeated loading which can lead to pavement failure. Different approaches are usually used to characterise fatigue resistance in asphalt mixtures including the phenomenological approach, the fracture mechanics approach and the dissipated energy approach. This paper presents a comparison of fatigue resistance calculated for different dissipated energy models using 2 Poi…

DAMPING AND MECHANICAL PROPERTIES OF DRY ASPHALT RUBBER FOR SUB-BALLAST LAYERS

2011

The passage of railway lines through a town or near built-up areas poses serious environmental problems such as noise and vibration. Consequently railway companies have shown an increasing interest in developing new materials with high mechanical and environmental performance. This paper presents the results of an experimental research on the potential application of Dry Asphalt Rubber (DAR) in sub-ballast layers by measuring its damping and mechanical properties. An experimental survey based on four point bending and Marshall tests was carried to measure the stiffness modulus and damping ratio both of a standard bituminous mixture and of dry asphalt rubber mixture with a rubber content equ…

I fenomeni vibrazionali generati dal transito dei vettori ferroviari: analisi FEM del comportamento meccanico del sistema sovrastruttura-terreno. Cas…

2006

Nel presente lavoro si è sviluppato un modello previsionale agli elementi finiti in grado di valutare l’impatto vibrazionale che l’infrastruttura ferroviaria arreca all’ambiente circostante, in particolare su alcuni punti dell’ammasso terroso latistante il binario, nella specifica configurazione di sezione trasversale in trincea. Il modello, simulando il processo di generazione e propagazione delle vibrazioni, ha consentito di valutare l’influenza sull’entità del fenomeno vibratorio di alcuni importanti parametri, progettuali e trasportistici, quali: la velocità di percorrenza del convoglio, la tipologia sovrastrutturale e le caratteristiche meccaniche del terreno.

An experimental investigation on the relationship between speed and road geometry

2004

In this work we had to face the topic of intrinsic road safety experimentally by investigating two interurban roads. These roads are characterised by different types of traffic. The results of the investigation are given in the form of prediction relations with their relevant speed diagrams. The present investigation, to be carried out in the field, intends to verify, on some sections considered as significant, the relationship and mutual incidence between the variables flow, road geometry and speed. In the processing of the results, use will also be made of specific instruments for evaluating the geometrical consistency of the road alignment in accordance with operating speed. Our experime…

ANALISI BEFORE-AFTER CON MODELLAZIONE MULTIVARIATA

2009

A multidisciplinary approach using LCCA and micro-simulation 10 model for the management of the urban pavements

2013

The maintenance and the rehabilitation of the urban road pavements are not often based on systematic program and scheduling but rather on emergency or on other not identified reasons. Moreover the Life Cycle Cost Analysis (LCCA), the only peculiar procedure for the management pavement, finds its own application for highway and motorway, even if it is possible to search the best investment for the urban interstate and arterials. By the light of the quantity of the involved resources, it seems necessary to define an operative methodology for programming the maintenance and rehabilitation activities for the urban pavement. The paper is oriented towards the development of a multidisciplinary ap…

An italian research on mechanical properties on asphalt with tire-rubber

2003

In Palermo a research study was initiated with following objectives: characterisation of the asphalt with tire rubber; study of pavements overlaid with this type of asphalt; cost estimation of asphalt rubber production process. This paper describes the first results achieved in the study concerning the mechanical properties of asphalt with tire rubber for road base and base course. In this research on dry process, more than 400 specimens have been tested at the DIIV laboratory for analysing the influences of crumb rubber modifier and powdered rubber modifier on the Marshall and indirect tensile test.

Modelling and experimental survey on ground borne vibration induced by rail traffic

2007

The ground borne vibrations, induced by the passage of trains, can propagate to the foundations of surrounding buildings. This phenomenon can be dangerous when the railway passes through a town or near built-up areas. Therefore the suitable numerical models for assessment the values of ground borne vibrations come in handy especially to the railway designers. In this paper it was developed a 3D FEM model of rail track-ground system, that takes into account the train characteristics, the type of rail track, the shape of rail cross-section (tunnel, embankment, cutting), the ground mechanical characteristics, the soil stratigraphy, the foundation type of surrounding buildings and the train spe…

THE DIAGNOSIS OF ROAD SURFACE DISTRESSES THROUGH IMAGE-BASED MODELING TECHNIQUES. EXPERIMENTAL SURVEY ON LABORATORY-RUTTED SAMPLES

2015

In the past few years, there has been a drastic increase in the use of image-based modeling (IBM) techniques to create high quality, reality-based 3D models. The low costs of these techniques, as well as their attractive visual quality, have led many researchers and professionals to invest their energy and resources in several tests. IBM is rarely used in the field of road surface distresses as diagnosis is usually performed using other techniques and devices. Road safety statistics reveal that about a half of the total number of accidents occur mainly due to the deterioration of the pavement. The goal of effective road network management is often incompatible with economic resources design…

Un modello F.E.M. 3D per valutare le vibrazioni in campo ferroviario

2009

UAV experimentation for pavement distresses detection

2022

In recent years, due to the high costs of traditional road failure detection techniques, the research has focused its attention on the use of the drone for the recognition of deterioration by experimenting with lowcost 3D detection techniques. The use of these techniques allows to carry out monitoring operations according to a structured and effective planning to guarantee the safety of users. The purpose of this paper is to verify the gradient that determines the loss of accuracy of the 3D acquisition as the flight altitude changes. in this way, the practitioner will have a handbook through which he can decide the altitude of the flight to obtain that degree of metric accuracy. The applica…

Pavement Management System model using a LCCA- microsimulation integrated approach

2014

The maintenance and the rehabilitation of the urban road pavements are not often based on systematic program and scheduling but rather on emergency or on other not identified reasons. Moreover the Life Cycle Cost Analysis (LCCA), the only peculiar procedure for the management pavement, finds its own application for highway and motorway, even if it is possible to search the best investment for the urban interstate and arterials. By the light of the quantity of the involved resources, it seems necessary to define an operative methodology for programming the maintenance and rehabilitation activities for the urban pavement. The paper is oriented towards the development of a multidisciplinary ap…

Indagine sperimentale sui segnali sonori all’interno dei rotabili per la diagnosi dello stato dell’armamento ferroviario

2003

The maintenance of track provides an relatively frequent operations. A good maintenance-planning allows to reduce the interference between rail traffic and maintenance operations. It is necessary so to use a monitoring system of track conditions. In this paper is showed an indirect monitoring system that correlates track conditions and typical spectrum of in-cab noise. The first results of experimental survey are reported.

STATE OF PRACTICE IN THE C&DW SECTOR WHILE PURSUING CIRCULAR ECONOMY: THE ITALIAN RECYCLED MATERIALS MARKET IN ROAD ENGINEERING

2022

Construction and demolition waste (C&DW) is mainly produced during the construction, demolition, or renovation activities of engineering structures and it accounts for a remarkable amount of the total C&DW generated, as it is estimated to be around 30%. This proportion differs across countries belonging to different types of economies and tends to be greater in countries with developing economies reaching 74% of total annual production. There is a plethora of applications that C&DW can be used for under a circular economic model and in this research study a focus is being given in the utilization of C&DW within the pavement engineering sector, and more specifically, in the u…

UN APPROCCIO BASATO SULLA MODELLAZIONE 3D E IL LIFE CYCLE ASSESSMENT PER UNA GESTIONE SOSTENIBILE DELLA MANUTENZIONE STRADALE

2021

Among several goals of the road agencies, one of the most relevant is the maintenance and rehabilitation of the road pavement. The growth of traffic, the longstanding lack of funding and, sometimes, an emergency-based planning of intervention, are common drivers leading to low level of pavement conditions in terms of ride quality and safety. In addition both cost and environmental concerns due to monitoring stage are relevant issues within the management system of local and urban road network, especially. With the purpose of implementing sustainability in the road pavement management, this paper provides an approach based on coupled low- cost 3D image modelling distress identification and L…

Una strategia operativa per la gestione della sicurezza autostradale

2006

Funzionalità e sicurezza di intersezioni stradali urbane. Un intervento progettuale nel campus universitario di Palermo

2008

Modellazione FEM del comportamento visco-elastoplastico di conglomerati bituminosi per uso stradale

2010

In questo lavoro si è voluto formulare un modello per descrivere il comportamento meccanico del conglomerato bituminoso di uso stradale che può essere facilmente implementato in programmi software FEM di uso comune, al fine di effettuare una rigorosa analisi strutturale delle pavimentazioni flessibili. Dopo una breve rassegna dei modelli costitutivi esistenti, a partire dai più semplici fino ai più complessi, è possibile concludere che un corretto metodo di modellazione consiste nel dividere la risposta del materiale, in termini di deformazione totale, nelle diverse componenti e di descriverle tutte separatamente. Nel confronto con i risultati sperimentali, il modello proposto è in grado di…

Misura della sicurezza stradale secondo le metodiche dell'Highway Safety Manual per gli interventi di adeguamento delle strade esistenti

2006

Comparing the Material Circularity Index of the Italian and Spanish motorways: A case study over the Mediterranean basin

2022

Closely following the attempt of the pavement engineering industry to comply with the principles of Circular Economy (CE) while simultaneously promoting its principles, it can be detected that a significant effort is being made towards the minimization of the energy and raw materials usually utilized. In this regard, Reclaimed Asphalt (RA) is a product that exhibits a tremendous exploitation potential. Knowing that by definition CE is restorative [1], regenerative, and aims to keep products, components, and materials at their highest utility and value at all times [2], i.e. it supports the “re-circulation” of materials and energy within the same or alternative product systems and thus the e…

An experimental research on the properties of Sicilian railroad ballast aggregates to the EN 13450:2002

2007

For the usual railway track, the railroad ballast is an fundamental factor for equally distributing all the loads and for drainage purposes. The railroad ballast still helps to correct eventual problems while building the railway. The railroad ballast aggregates have to be gifted with specific requisites in terms of physical and mechanical characteristics. The European Standard EN 13450:2002 specifies the properties of aggregates obtained by processing natural or manufactured materials or recycled crushed unbound aggregates for use in construction of railway track. Such standard provides for the evaluation of conformity of products to this European Standard. The knowledge of ballast charact…

Stato dell’arte degli interventi sulla sorgente per la mitigazione delle vibrazioni generate da sistemi di trasporto su ferro

2008

La crescente esigenza di mobilità registrata negli ultimi anni in molte città italiane ha condotto all’elaborazione di importanti progetti per la realizzazione, o l’ampliamento, di reti di trasporto di massa in ambito urbano. In molti casi le scelte progettuali prevedono la realizzazione di infrastrutture su ferro, come tram, metropolitana, o ferrovia urbana. Tuttavia, soprattutto nelle città caratterizzate da importanti patrimoni edilizi storici, la realizzazione di tali tipologie infrastrutturali comporta enormi problemi di inserimento ambientale dovuti agli impatti acustici e vibrazionali prodotti dall’esercizio dei vettori. Un caso emblematico che ha mobilitato l’attenzione pubblica, na…

Image-based 3D reconstruction using traditional and mobile-phone data-sets for road pavement distress analysis

2021

The issue of road networks being in deplorable conditions is one that is widespread globally. One of the main precursors for this is that when preparing maintenance management systems, many road agencies rely on data which is often outdated or inaccurate. This is due in many cases to insufficient budgets which are unable to adequately address both maintenance and rehabilitation. It is therefore critical that road agencies have better tools at their disposal to help combat these issues. One of the possible techniques that have been identified is the use of structure from motion techniques to adequately identify road pavement distresses. This paper advances previous work in this area and expl…

Predicting tire/pavement noise impact reduction using numerical simulation and experimental data for open graded asphalt mixture

2013

The environmental impact of noise from roads and highways traffic is relevant in urban and rural areas. The use of open-graded asphalt pavements reduces significantly the noise, entrapping the acoustic waves inside the porous structure of the material. In this paper we propose a simulation approach in order to predict the acoustic properties of the asphalt mixture from geometrical and topological indicators. In detail we have generated, using a Random Sequential Adsorption model, synthetic samples starting from the same grading and bitumen contents of real samples manufactured in laboratory. We have measured the acoustic adsorption coefficient of the real samples and we have investigated th…

Studio di conglomerati bituminosi con granulato di gomma proveniente da pneumatici dismessi

2002

La ricerca di conglomerati bituminosi di elevate prestazioni sovente si associa allo studio delle implicazioni ambientali che la produzione, la posa in opera e l’esercizio di tali materiali comportano. Un aspetto assai importante, in tal senso, è l’opportunità che alcune modalità produttive offrono in termini di un ridotto consumo di inerti e del contestuale impiego di materiali destinati a discarica che, invece, vengono inseriti in processi di riciclaggio. È questo il caso della gomma proveniente dal riciclaggio industriale di pneumatici dismessi che, negli Stati Uniti ed in Canada, è divenuta una fonte sostanziosa per la realizzazione di conglomerati bituminosi. La presente ricerca, dopo …

Verifica sperimentale delle correlazioni tra i parametri di compattazione in laboratorio e in situ delle miscele bituminose

2006

Indagine sperimentale sul binomio velocità geometria stradale

2005

La convinta assunzione in campo progettuale di modelli comportamentali, atti ad interpretare i processi di guida su strada attesta la rilevanza riconosciuta al ruolo dell'utente nel determinare le condizioni di sicurezza di una infrastruttura. Particolarmente complesso è il legame tra l'utente e l'ambiante stradale, nella sua accezione di contesto composto dalla strada e dalle sue aree limitrofe, dal traffico veicolare, dalle circostanze metereologiche e climatiche.

Indagine di laboratorio sulla permeabilità dei conglomerati bituminosi aperti

2010

I conglomerati bituminosi aperti utilizzati nelle pavimentazioni drenanti-fonoassorbenti devono garantire in opera precise e specifiche prestazioni in termini di conducibilità idraulica e rifrazione acustica, la cui quantificazione è demandata a indagini da effettuare “a posteriori” sulla sovrastruttura già realizzata. Questa prassi, registrata e regolata dai principali e più significativi Capitolati speciali per opere stradali, mostra un notevole limite qualora si voglia stabilire “a priori” il livello di prestazione del conglomerato, misurando il valore della grandezza in esame - per esempio la permeabilità - già in ambito di laboratorio e progettando di conseguenza la miscela, intervenen…

The volumetric mix-design of porous asphalt: an Italian study of Ndesign determination

2007

Image Based Modeling Technique for Pavement Distress surveys: a Specific Application to Rutting

2016

Image-based modeling (IBM) is a well-known technique to obtain high quality 3D models based on multi view images. IBM started being used in several applications such as inspection, identification of objects and visualization, due to the user-friendly approach, the low cost and highly automated technique. This paper focuses on the investigation of the potential application of IBM in the diagnosis of road pavement distresses and in particular rutting. Indeed, the evaluation of the rutting distress is a fundamental step to define the whole state of a pavement as demonstrated by the calculation of Present Serviceability Index (PSI). Currently, the permanent deformation is measured monitoring vi…

Understanding the current state of practice in the construction and demolition waste sector through the lenses of circular economy: The Italian recyc…

Construction and demolition waste (CeDw) is mainly produced during the construction, demolition, or renovation activities of civil engineering structures and it accounts for a remarkable amount of the total C&Dw generated, as it is estimated to be around 30%. This proportion differs between countries belonging to different types of economies and tends to be greater in countries with developing economies reaching 74% of total annual production. There is a plethora of applications that C&Dw can be used for under a circular economic model and in this research a focus is being given in the exploitation of C&Dw within the pavement engineering sector, and more specifically, in the uti…

Verifica sperimentale delle correlazioni tra i parametri di compattazione in laboratorio e in situ delle miscele bituminose

2007

Il Rilievo MMS di tracciati autostradali

2009

Già da alcuni anni alcuni autori hanno messo in risalto come, anche in ambito autostradale, la geometria d’asse intesa come il complesso plano-altimetrico degli elementi di tracciato, eserciti un ruolo non marginale sulla condotta di guida dell’utente. Grazie alle metodologie di verifica della coerenza della linea d’asse di tracciato (Design Consistency), si accerta o meno che esista un’armonica correlazione tra parametri geometrici significativi e la velocità, di progetto od operativa, del tronco considerato. L’espressione grafica di tale correlazione è il cosiddetto diagramma delle velocità, dalla cui analisi, secondo criteri invero peculiari di infrastrutture viarie non autostradali, è p…

EXPERIMENTAL INVESTIGATION ON DRY ASPHALT RUBBER FOR SUBBALLAST

2011

The asphalt rubber mixes have a wide application field in the railroad and road superstructures because of their technical and environmental properties. While in many countries the wet process is often used to make bituminous mixtures, the dry process doesn’t have the same degree of application even though a larger recycling of waste tires rubber is allowed than the dry process. This paper focuses on the mix-design of the Dry Asphalt Rubber (DAR) for subballast of the railroad superstructure in order to define a sound laboratory procedure of mix-design with reference to Marshall test and Superpave Gyratory Compactor (SGC) test. The comparison between Marshall test and SGC test highlights th…

Experimental Survey on Dry Asphalt Rubber Concrete for Sub-ballast Layers

2012

The railway traffic through a town or near built-up areas causes heavy effects such as noise and vibration on surroundings. In order to minimize the level of these impacts the railway companies with researchers and practitioners seek suitable solutions especially in the field of the rail-track because the main source of the ground borne vibrations and noise is the bad wheel-track contact. In particular, a big effort is addressed to new materials with high mechanical and environmental performance that can be utilized within the sub-ballast layer. This paper presents the results of an experimental survey on the potential application of Dry Asphalt Rubber Concrete (DARC) in sub-ballast layers …

A multi-objective approach based on the genetic algorithm technique for road pavement maintenance

2007

A MODEL OF DYNAMIC INTERACTION BETWEEN A TRAIN VEHICLE AND A RAIL TRACK

2007

Study of the effectiveness of the open trenches in reducing railway ground-borne vibrations: sensitivity analysis of its geometric features using art…

2009

Stato dell’arte degli interventi sul mezzo recettore e di propagazione per la mitigazione delle vibrazioni generate da sistemi di trasporto su ferro

2008

La generazione e la propagazione delle onde vibrazionali da una sorgente, ferroviaria o tranviaria, all’ambiente circostante è un problema complesso che risulta influenzato da vari fattori tra loro correlati: le caratteristiche e le condizioni della sovrastruttura, il peso, la velocità e le caratteristiche meccaniche del veicolo, le proprietà dinamiche e stratigrafiche del terreno, le caratteristiche dinamiche degli edifici recettori. Di tali aspetti occorre tenere conto ai fini della realizzazione di efficaci misure di mitigazione. Nella presente memoria vene riportato lo stato dell’arte relativo agli interventi sul mezzo di propagazione (suolo e sottosuolo) e sul mezzo recettore (opere di…

Revisione dei requisiti di accettazione per gli aggregati - Indagini sperimentali e proposte metodologiche

2006

Modello fuzzy di calcolo della distanza di visibilità per il sorpasso su strade extraurbane ad unica carreggiata bidirezionale

2002

Lo studio di modelli teorici che ben rappresentino, nella loro articolazione, le manovre di guida in sede stradale è da sempre un esercizio tanto praticato quanto complesso. La difficoltà di delineare compiutamente tali manovre, di definirne l’interazione cinematica dei veicoli coinvolti è comprovata dalla varietà di modelli presenti in letteratura. Con il presente lavoro ci si propone di pervenire alla formulazione di un modello originale di calcolo della distanza di visibilità per il sorpasso su strade bidirezionali ad unica carreggiata, il quale tenga debitamente conto del coacervo delle variabili cinematiche, meccaniche, geometriche, ambientali e di traffico, così come del comportamento…

Le vibrazioni in campo ferroviario: analisi f.e.m. dell’interazione convoglio-sovrastruttura-terreno

2003

This paper describes the formulation and application of a finite element method model that simulates the generation and propagation of train-induced vibrations into track-ground system. The F.E.M. model accounts for the interaction between ground, railway, shape of cross-section and train speed. The aim of this research is the evaluation of the influence of each factor on vibrational phenomena.