Indagine sperimentale per la valutazione del comfort acustico nelle carrozze ferroviarie
In questo lavoro, reso possibile dall’interesse e dalla disponibilità mostrata concreta-mente dalla Divisione Trasporto Regionale di Trenitalia (Direzione Regionale Sicilia), sono stati approfonditi alcuni aspetti concernenti i fenomeni acustici all’interno dei rotabili fer-roviari, al fine di individuare eventuali legami tra le caratteristiche del sistema costituito dal binomio tracciato-rotabile e le condizioni di comfort acustico dei passeggeri. Una indagine sperimentale di rilevamento delle condizioni acustiche è stata condotta su alcune vetture di convogli operativi su una linea ferroviaria che attraversa il territorio della provincia di Palermo su tracciato misto, urbano ed extraurban…
Exploiting Low-Cost 3D Imagery for the Purposes of Detecting and Analyzing Pavement Distresses
Road pavement conditions have significant impacts on safety, travel times, costs, and environmental effects. It is the responsibility of road agencies to ensure these conditions are kept in an acceptable state. To this end, agencies are tasked with implementing pavement management systems (PMSs) which effectively allocate resources towards maintenance and rehabilitation. These systems, however, require accurate data. Currently, most agencies rely on manual distress surveys and as a result, there is significant research into quick and low-cost pavement distress identification methods. Recent proposals have included the use of structure-from-motion techniques based on datasets from unmanned a…
Investigating the Viability of Multi-Recycling of Asphalt Mixtures through a Preliminary Binder Level Characterization
The incorporation of reclaimed asphalt (RA) in hot mix asphalt mixtures is widely considered a sustainable solution for road infrastructure development. Under the scope of the circular economy (CE), the multiple recycling capability of RA has to be assessed in order to ensure its performance at each recycling cycle and also its viability with different additives. The performance of asphalt mixtures with RA strongly depends on the type of rejuvenator, binder, and their degree of blending in the mix. For this reason, it is essential to know the properties of the aged binder extracted from RA to better understand its rheological properties and optimal dosage of rejuvenation to design a satisfa…
A framework for defining a sustainability rating system for railway track-beds
Railways perform a significant role in the transportation system and they have relevant environmental, economic and social impacts. They are currently engineered optimizing every singular aspect rather than considering a broader system for improving the sustainability of the overall infrastructure. Thus, it is necessary to promote an effort to define a global sustainability framework for conceiving the design, construction and management of railway infrastructure. The Sustainable Rating System (SRS) proposed in this paper is a tool under development that evaluates different alternatives of railway track-bed structure. Inspired by similar efforts in the field of road engineering such as Gree…
From Buildings' End of Life to Aggregate Recycling under a Circular Economic Perspective: A Comparative Life Cycle Assessment Case Study
The demolition of buildings, apart from being energy intensive and disruptive, inevitably produces construction and demolition waste (C&Dw). Unfortunately, even today, the majority of this waste ends up underexploited and not considered as valuable resources to be re-circulated into a closed/open loop process under the umbrella of circular economy (CE). Considering the amount of virgin aggregates needed in civil engineering applications, C&Dw can act as sustainable catalyst towards the preservation of natural resources and the shift towards a CE. This study completes current research by presenting a life cycle inventory compilation and life cycle assessment case study of two buildin…
Analytical approach for the mix design optimisation of bituminous mixtures with crumb rubber
The present paper provides a basis for defining a mix design method specifically tailored to rubberised asphalt that takes into account the behaviour of crumb rubber. An analytical approach to quantifying the recovered deformation of crumb rubber in the post-compaction phase has been developed in order to adjust the number of gyrations proposed by the Superpave method for compacting specimens of hot mix asphalt using a Superpave gyratory compactor. The maximum allowable amount of rubber has been calculated. Finally, a step-by-step protocol has been proposed in order to fabricate and compact crumb rubber modified mixtures with the gyratory compactor.
Linear and nonlinear fractional hereditary constitutive laws of asphalt mixtures
The aim of this paper is to propose a fractional viscoelastic and viscoplastic model of asphalt mixtures using experimental data of several tests such as creep and creep recovery performed at different temperatures and at different stress levels. From a best fitting procedure it is shown that both the creep one and recovery curve follow a power law model. It is shown that the suitable model for asphalt mixtures is a dashpot and a fractional element arranged in series. The proposed model is also available outside of the linear domain but in this case the parameters of the model depend on the stress level.
Towards Low-Cost Pavement Condition Health Monitoring and Analysis Using Deep Learning
Governments are faced with countless challenges to maintain conditions of road networks. This is due to financial and physical resource deficiencies of road authorities. Therefore, low-cost automated systems are sought after to alleviate these issues and deliver adequate road conditions for citizens. There have been several attempts at creating such systems and integrating them within Pavement management systems. This paper utilizes replicable deep learning techniques to carry out hotspot analyses on urban road networks highlighting important pavement distress types and associated severities. Following this, analyses were performed illustrating how the hotspot analysis can be carried out to…
Increasing the Use of Reclaimed Asphalt in Italy towards a Circular Economy: A Top-Down Approach
This contribution concerns recommendations which could be made to Italian regulatory bodies to improve their use of reclaimed asphalt (RA) in the road engineering sector. It is essential for the use of RA to be established as a standard practice since it has been proven that it can serve as an end-of-waste product that complies with the principles of a circular economy within both an open- and a closed-loop approach [1,2]. Several aspects will be covered, starting with an analysis of European nations whose economies can be classed as “more circular” compared to Italy’s. This refers to nations which have a high usage of RA. Furthermore, nations which have clear regulatory guidelines on the u…
Super-Resolution Images Methodology Applied to UAV Datasets to Road Pavement Monitoring
The increasingly widespread use of smartphones as real cameras on drones has allowed an ever-greater development of several algorithms to improve the image’s refinement. Although the latest generations of drone cameras let the user achieve high resolution images, the large number of pixels to be processed and the acquisitions from multiple lengths for stereo-view often fail to guarantee satisfactory results. In particular, high flight altitudes strongly impact the accuracy, and result in images which are undefined or blurry. This is not acceptable in the field of road pavement monitoring. In that case, the conventional algorithms used for the image resolution conversion, such as the bilinea…