L'impiego della pressa giratoria per il costipamento dei conglomerati bituminosi e attualment... more L'impiego della pressa giratoria per il costipamento dei conglomerati bituminosi e attualmente prevista nelle piu avanzate Norme Tecniche di Capitolato per lavori stradali. Per fornire un contributo alla diffusione di questa attrezzatura anche in Italia, nella presente memoria gli Autori espongono i risultati ottenuti operando su una serie di miscele prelevate in vari cantieri di lavori di costruzione e manutenzione di pavimentazioni. Le indagini sono state strutturate in modo tale da prendere in considerazione una serie di fattori che influenzano sia la curva di lavorabilita delle miscele, sia le caratteristiche volumetriche dei campioni al termine della compattazione: tipo di miscela (per base, binder o usura); tipo di bitume (modificato oppure no); temperatura di costipamento; diametro della fustella (100 o 150 mm); modalita di costipamento (a numero di giri o ad altezza imposta). A titolo comparativo sono stati inoltre preparati campioni con la tradizionale procedura Marshal...
Negli ultimi anni il trasporto aereo ha fortemente beneficiato della generale crescita della doma... more Negli ultimi anni il trasporto aereo ha fortemente beneficiato della generale crescita della domanda di mobilita. Se fino a pochi anni fa le compagnie aeree erano prevalentemente impegnate nei collegamenti tra i grandi scali, potendo contare principalmente su una clientela consolidata legata alle relazioni d'affari, oggi la maggiore concorrenza tra le compagnie e l'abbattimento delle tariffe hanno creato le condizioni affinche, anche sulle brevi distanze, vi sia una maggiore competitivita con gli altri sistemi di trasporto. Soprattutto l'avvio di nuove relazioni sulle brevi e medie distanze verso gli aeroporti considerati minori, ha permesso alle maggiori compagnie aeree di calamitare quei flussi legati al turismo e alle relazioni sociali sia tra le localita d'importanza regionale, sia da queste verso le grandi citta. L'impiego di vettori di piccolo e medio raggio d'azione su queste tratte, ha permesso l'impiego di velivoli ad elevata capacita nei sempre ...
La messa in sicurezza delle infrastrutture stradali e indispensabile per la riduzione dell???inci... more La messa in sicurezza delle infrastrutture stradali e indispensabile per la riduzione dell???incidentalita e della mortalita ad essa associata. In ambito urbano, dove avviene il 75% degli incidenti totali, le molteplici categorie di utenti vulnerabili (es. guidatori, ciclisti, pedoni) interagiscono in modo conflittuale per l???elevato numero di punti d???intersezione tra correnti di traffico tra loro diverse per velocita, prestazioni e occupazione. Un deciso miglioramento delle condizioni di sicurezza e attuabile attraverso il soddisfacimento di minime condizioni di visibilita reciproca tra i diversi utenti nei potenziali punti di conflitto. Lo spazio di visibilita disponibile (SVD) dal punto di osservazione dell???utente, ossia lo spazio che separa l???utente dal punto visibile piu lontano lungo la sua traiettoria, dovrebbe essere superiore a quello necessario all???esecuzione delle piu rilevanti manovre di guida, su tutte l???arresto di emergenza. In questo lavoro si presenta l???...
Le miscele di conglomerato bituminoso che vengono impie¬gate in campo stradale possiedono caratte... more Le miscele di conglomerato bituminoso che vengono impie¬gate in campo stradale possiedono caratteristiche volumetri¬che e meccaniche che variano a seconda della posizione da esse occupata all'interno della sovrastruttura. Tali proprieta vengono generalmente prese in esame tanto nel controllo di qualita quanto nei procedimenti di mix design, e risultano intimamente legate tra loro. Cio e stato confermato dalle con¬clusioni dello Strategic Highway Research Program (SHRP) che individua nella formulazione volumetrica il punto di partenza degli ap-procci di studio di livello avanzato [1]. La percentuale dei vuoti e la proprieta volume¬trica di gran lunga piu importante sia per i conglomerati bituminosi chiusi, per i quali si richiedono percentuali dei vuoti quasi mai supe¬riori al 4-5%, sia per quelli drenanti per i quali si sale al 20% ed oltre. Essa dipende non solo dalla ricetta prescelta ma an¬che dalle caratteristiche di forma e tessitura superficiale dei materiali lapidei, dall...
Il Metodo dei Vuoti si colloca tra i metodi analitico-volumetrici di mix-design con i quali vengo... more Il Metodo dei Vuoti si colloca tra i metodi analitico-volumetrici di mix-design con i quali vengono definite miscele di conglomerato bituminoso aventi le desiderate caratteristiche volumetriche. Nella presente memoria vengono illustrati i piu recenti risultati ottenuti nello sviluppo del Metodo dei Vuoti facendo riferimento alle sperimentazioni compiuta nel corso degli ultimi cinque anni nel Laboratorio Materiali Stradali del Politecnico di Torino. In primo luogo viene proposto, grazie all�analisi dei risultati ottenuti su miscele derivanti dalla sistematica combinazione di aggregati e leganti di diverse origini, un aggiornamento della formula di progetto di origine sperimentale inclusa nel modello. Tale formula viene inoltre presentata in una duplice versione per potere distinguere il caso dell�impiego della tradizionale tecnica di costipamento Marshall da quello relativo all'�uso della pressa a taglio giratorio. Con riferimento ai campioni di prova preparati con quest�ultima m...
The growing population in urban areas worldwide is having a severe impact on the environment and ... more The growing population in urban areas worldwide is having a severe impact on the environment and quality of life of inhabitants. To alleviate the impact on traditional transportation infrastructures, existing and future urban facilities must be more environmentally friendly and sustainable. One solution is to develop new "green transportation infrastructures" (GTI) as part of the urban storm water management system. Although technologies for GTI have been well-investigated, there is limited experience of their potential benefits globally and, specifically, in Italy. This work, funded by the Regione Piemonte in 2015 and supported by different areas of expertise, aimed at promoting new urban storm water systems through the retention, filtration, and restoration of natural soil water content. To this end, a laboratory investigation of porous road pavements (Figure 1), and vegetated boxes (Figure 2 and 3) that filter runoff pollutants from impervious pavements was conducted to...
Pervious concrete (PC) pavements are water control systems for infiltrating storm water, reducing... more Pervious concrete (PC) pavements are water control systems for infiltrating storm water, reducing runoffs, contrasting heat-island effects and noise diffusion in urban environments. Their poor strength and stiffness, which stem from their porosity, limit their application for use in sidewalks and residential streets. To overcome this limitation, the research aimed at developing an alkali-activated blast furnace slag binder (AA-BFS) which, when added to the concrete mixture, would enable it to attain the characteristics required for application in trafficked road pavements. A Portland cement (CEM-I) and a blast furnace cement (CEM-III/C) were included for comparison purposes. Standard and high-performance pervious concrete (HPPC) mortars were tested with the same mix ratio of binder, sand, and admixtures. The effects of a latex polymer admixture were also analysed. After 2, 7, and 28 days of curing, AA-BFS mortars exhibited the greatest flexural and compressive strengths. As expected...
High volumes of construction and demolition waste (CDW) are continuously produced worldwide. The ... more High volumes of construction and demolition waste (CDW) are continuously produced worldwide. The European Commission aims to increase the recycling of non hazardous CDW to a minimum of 70% in weight terms by 2020. Hence, there is increasing pressure on researchers to focus on the valorization of these alternative materials for use in the world of construction alongside traditional materials. CDW contains materials from excavation and/or demolition and are typically heterogeneous in terms of composition, grain size, and toughness; furthermore, some particles are more sensitive to degradation processes than others. In order to increase durability while maintaining sufficient strength levels, one solution consists of chemical stabilization with cementitious binders. The paper illustrates the results of a laboratory investigation into the stabilization of CDW using cement kiln dust (CKD). Compared to ordinary Portland cements, CKD exhibits a weak binding attitude due to the limited cont...
The strategy of 30 km/h zones, referred to in the international context as "traffic calming" meas... more The strategy of 30 km/h zones, referred to in the international context as "traffic calming" measures, serves to safeguard pedestrians, cyclists and motorcyclists, collectively referred to as "vulnerable road users" (VRU). Its main function is to compel drivers to observe a maximum speed limit of 30 km/h. However, urban infrastructure transformations modify traffic collision patterns and the involvement of road users, with a spatial temporal redistribution of events. This work seeks to study the effects on collision distribution resulting from the introduction of a 30 km/h zone to the Mirafiori Nord area in the city of Turin in late 2008. Collision frequencies, based on data provided by the Italian National Institute of Statistics (ISTAT), were evaluated over the period 2006-2016. Road traffic collisions involving both VRU and motorized users ("noVRU") were taken into account. Decreases in collision frequency were found for noVRU related crashes, while the VRU crash rate remained essentially unchanged with only minor fluctuations consistent with the regression to the mean phenomenon. The countermeasures, which sought to protect VRU, were however very effective for noVRU. As the effects of each structural modification spill over into neighboring areas, the analysis of collision frequency was extended to a study area greater than the one in which the 30 km/h zone was realized. In fact, due to the migration of events, the reduction in the collision frequency in the speed restricted zone was accompanied by an increase in the same frequency in the immediate surrounding area.
Curves represent the most interesting element to be analyzed when evaluating the operational and ... more Curves represent the most interesting element to be analyzed when evaluating the operational and safety effects of road geometrics. Despite the existence of several static and dynamic survey techniques, the correct identification of curves and the interpretation of spatial data from horizontal road alignment surveys still represent a challenge. The paper presents the results of an investigation into the effects of both accuracy and sampling frequency (i.e., the interval between data points) of alignment spatial data on the identification of the radius and center of curvature. In pursuit of this objective, the authors adopted an original approach consisting of the generation of dispersed spatial data points from circular arcs with known characteristics. The Least Squares, Huber and Landau methods were used to back-calculate the radius and the coordinates of the center of curvature, and to assess the effects of accuracy and interval between data points. The results obtained quantified the effects of accuracy, interval between points, radius magnitude, and length of circular arc on the identification of circular arcs. In support of future survey activities, considerations regarding the accuracy of measurements, the sampling frequency, and arc characteristics (i.e., length, radius) are discussed in the paper.
Transportation Research Record: Journal of the Transportation Research Board
Most existing roads were designed without considering the improved performance of modern vehicles... more Most existing roads were designed without considering the improved performance of modern vehicles and the new onboard technologies available for assisted driving. In addition, vehicles frequently travel at speeds that exceed the maximum considered in road design. For these reasons, the need for speed- and safety-related countermeasures (e.g., field control, mobile or fixed speed cameras, traffic calming measures) is evident. However, these countermeasures are only partially effective and the proportion of crashes that are speed-related remains significant. This investigation is aimed at the development of a new intelligent speed adaptation (ISA) system based on the available sight distance (ASD). In conditions of poor visibility, the system can (i) inform drivers when they are traveling at inappropriate speeds, or (ii) generate warning sounds to the same effect, or (iii) intervene directly and compel the vehicle to adopt the speed which is most appropriate to the particular ASD. As ...
The available sight distance (ASD) is that part of the roadway ahead which is visible to the driv... more The available sight distance (ASD) is that part of the roadway ahead which is visible to the driver, and should be of sufficient length to allow a vehicle traveling at the designated speed to stop before reaching a stationary object in its path. It is fundamental in assessing road safety of a project or on an existing road section. Unfortunately, an accurate estimation of the available sight distance is still an issue on existing roads, above all due to the lack of information regarding the as-built condition of the infrastructure. Today, the geomatics field already offers different solutions for collecting 3D information about environments at different scales, integrating multiple sensors, but the main issue regarding existing mobile mapping systems (MMSs) is their high cost. The first part of this research focused on the use of a low-cost MMS as an alternative for obtaining 3D information about infrastructure. The obtained model can be exploited as input data of specific algorithm...
Transportation Research Part F: Traffic Psychology and Behaviour, 2016
Operating speeds on roads are influenced by lighting conditions: indeed most of the driving tasks... more Operating speeds on roads are influenced by lighting conditions: indeed most of the driving tasks are influenced by visual information. In terms of supporting evidence, there is a significant volume of published research that demonstrates how safety is affected by road geometrics and environmental lighting conditions. However, only a few studies have investigated the contextual impact of these factors on driver speed behaviour, which in turn is considered one of the most important variables affecting road safety. In this paper, speed distributions have been modelled using environmental parameters related to both road geometrics and lighting conditions. To achieve this, the authors compiled a comprehensive database in which geometric characteristics, speeds, illuminance and luminance are available for both night-time and daytime conditions. The results show that average speeds and deviations from the mean are significantly affected by changes in lighting parameters for the different conditions (sunny, cloudy, and dark) considered in this study. Knowing the effects of such parameters on operating speed is fundamental for effective road management policies, especially on urban roads where, notably, the highest number of accidents occur.
The most effective way to reduce vehicle speed on urban low volume roads, such as residential str... more The most effective way to reduce vehicle speed on urban low volume roads, such as residential streets, is the installation of traffic calming systems such as speed humps and tables. In those roads in which these measures are applied, a reduction in traffic volume and accidents is generally observed, with clear benefits for pedestrians, bicyclists and residents.
L'impiego della pressa giratoria per il costipamento dei conglomerati bituminosi e attualment... more L'impiego della pressa giratoria per il costipamento dei conglomerati bituminosi e attualmente prevista nelle piu avanzate Norme Tecniche di Capitolato per lavori stradali. Per fornire un contributo alla diffusione di questa attrezzatura anche in Italia, nella presente memoria gli Autori espongono i risultati ottenuti operando su una serie di miscele prelevate in vari cantieri di lavori di costruzione e manutenzione di pavimentazioni. Le indagini sono state strutturate in modo tale da prendere in considerazione una serie di fattori che influenzano sia la curva di lavorabilita delle miscele, sia le caratteristiche volumetriche dei campioni al termine della compattazione: tipo di miscela (per base, binder o usura); tipo di bitume (modificato oppure no); temperatura di costipamento; diametro della fustella (100 o 150 mm); modalita di costipamento (a numero di giri o ad altezza imposta). A titolo comparativo sono stati inoltre preparati campioni con la tradizionale procedura Marshal...
Negli ultimi anni il trasporto aereo ha fortemente beneficiato della generale crescita della doma... more Negli ultimi anni il trasporto aereo ha fortemente beneficiato della generale crescita della domanda di mobilita. Se fino a pochi anni fa le compagnie aeree erano prevalentemente impegnate nei collegamenti tra i grandi scali, potendo contare principalmente su una clientela consolidata legata alle relazioni d'affari, oggi la maggiore concorrenza tra le compagnie e l'abbattimento delle tariffe hanno creato le condizioni affinche, anche sulle brevi distanze, vi sia una maggiore competitivita con gli altri sistemi di trasporto. Soprattutto l'avvio di nuove relazioni sulle brevi e medie distanze verso gli aeroporti considerati minori, ha permesso alle maggiori compagnie aeree di calamitare quei flussi legati al turismo e alle relazioni sociali sia tra le localita d'importanza regionale, sia da queste verso le grandi citta. L'impiego di vettori di piccolo e medio raggio d'azione su queste tratte, ha permesso l'impiego di velivoli ad elevata capacita nei sempre ...
La messa in sicurezza delle infrastrutture stradali e indispensabile per la riduzione dell???inci... more La messa in sicurezza delle infrastrutture stradali e indispensabile per la riduzione dell???incidentalita e della mortalita ad essa associata. In ambito urbano, dove avviene il 75% degli incidenti totali, le molteplici categorie di utenti vulnerabili (es. guidatori, ciclisti, pedoni) interagiscono in modo conflittuale per l???elevato numero di punti d???intersezione tra correnti di traffico tra loro diverse per velocita, prestazioni e occupazione. Un deciso miglioramento delle condizioni di sicurezza e attuabile attraverso il soddisfacimento di minime condizioni di visibilita reciproca tra i diversi utenti nei potenziali punti di conflitto. Lo spazio di visibilita disponibile (SVD) dal punto di osservazione dell???utente, ossia lo spazio che separa l???utente dal punto visibile piu lontano lungo la sua traiettoria, dovrebbe essere superiore a quello necessario all???esecuzione delle piu rilevanti manovre di guida, su tutte l???arresto di emergenza. In questo lavoro si presenta l???...
Le miscele di conglomerato bituminoso che vengono impie¬gate in campo stradale possiedono caratte... more Le miscele di conglomerato bituminoso che vengono impie¬gate in campo stradale possiedono caratteristiche volumetri¬che e meccaniche che variano a seconda della posizione da esse occupata all'interno della sovrastruttura. Tali proprieta vengono generalmente prese in esame tanto nel controllo di qualita quanto nei procedimenti di mix design, e risultano intimamente legate tra loro. Cio e stato confermato dalle con¬clusioni dello Strategic Highway Research Program (SHRP) che individua nella formulazione volumetrica il punto di partenza degli ap-procci di studio di livello avanzato [1]. La percentuale dei vuoti e la proprieta volume¬trica di gran lunga piu importante sia per i conglomerati bituminosi chiusi, per i quali si richiedono percentuali dei vuoti quasi mai supe¬riori al 4-5%, sia per quelli drenanti per i quali si sale al 20% ed oltre. Essa dipende non solo dalla ricetta prescelta ma an¬che dalle caratteristiche di forma e tessitura superficiale dei materiali lapidei, dall...
Il Metodo dei Vuoti si colloca tra i metodi analitico-volumetrici di mix-design con i quali vengo... more Il Metodo dei Vuoti si colloca tra i metodi analitico-volumetrici di mix-design con i quali vengono definite miscele di conglomerato bituminoso aventi le desiderate caratteristiche volumetriche. Nella presente memoria vengono illustrati i piu recenti risultati ottenuti nello sviluppo del Metodo dei Vuoti facendo riferimento alle sperimentazioni compiuta nel corso degli ultimi cinque anni nel Laboratorio Materiali Stradali del Politecnico di Torino. In primo luogo viene proposto, grazie all�analisi dei risultati ottenuti su miscele derivanti dalla sistematica combinazione di aggregati e leganti di diverse origini, un aggiornamento della formula di progetto di origine sperimentale inclusa nel modello. Tale formula viene inoltre presentata in una duplice versione per potere distinguere il caso dell�impiego della tradizionale tecnica di costipamento Marshall da quello relativo all'�uso della pressa a taglio giratorio. Con riferimento ai campioni di prova preparati con quest�ultima m...
The growing population in urban areas worldwide is having a severe impact on the environment and ... more The growing population in urban areas worldwide is having a severe impact on the environment and quality of life of inhabitants. To alleviate the impact on traditional transportation infrastructures, existing and future urban facilities must be more environmentally friendly and sustainable. One solution is to develop new "green transportation infrastructures" (GTI) as part of the urban storm water management system. Although technologies for GTI have been well-investigated, there is limited experience of their potential benefits globally and, specifically, in Italy. This work, funded by the Regione Piemonte in 2015 and supported by different areas of expertise, aimed at promoting new urban storm water systems through the retention, filtration, and restoration of natural soil water content. To this end, a laboratory investigation of porous road pavements (Figure 1), and vegetated boxes (Figure 2 and 3) that filter runoff pollutants from impervious pavements was conducted to...
Pervious concrete (PC) pavements are water control systems for infiltrating storm water, reducing... more Pervious concrete (PC) pavements are water control systems for infiltrating storm water, reducing runoffs, contrasting heat-island effects and noise diffusion in urban environments. Their poor strength and stiffness, which stem from their porosity, limit their application for use in sidewalks and residential streets. To overcome this limitation, the research aimed at developing an alkali-activated blast furnace slag binder (AA-BFS) which, when added to the concrete mixture, would enable it to attain the characteristics required for application in trafficked road pavements. A Portland cement (CEM-I) and a blast furnace cement (CEM-III/C) were included for comparison purposes. Standard and high-performance pervious concrete (HPPC) mortars were tested with the same mix ratio of binder, sand, and admixtures. The effects of a latex polymer admixture were also analysed. After 2, 7, and 28 days of curing, AA-BFS mortars exhibited the greatest flexural and compressive strengths. As expected...
High volumes of construction and demolition waste (CDW) are continuously produced worldwide. The ... more High volumes of construction and demolition waste (CDW) are continuously produced worldwide. The European Commission aims to increase the recycling of non hazardous CDW to a minimum of 70% in weight terms by 2020. Hence, there is increasing pressure on researchers to focus on the valorization of these alternative materials for use in the world of construction alongside traditional materials. CDW contains materials from excavation and/or demolition and are typically heterogeneous in terms of composition, grain size, and toughness; furthermore, some particles are more sensitive to degradation processes than others. In order to increase durability while maintaining sufficient strength levels, one solution consists of chemical stabilization with cementitious binders. The paper illustrates the results of a laboratory investigation into the stabilization of CDW using cement kiln dust (CKD). Compared to ordinary Portland cements, CKD exhibits a weak binding attitude due to the limited cont...
The strategy of 30 km/h zones, referred to in the international context as "traffic calming" meas... more The strategy of 30 km/h zones, referred to in the international context as "traffic calming" measures, serves to safeguard pedestrians, cyclists and motorcyclists, collectively referred to as "vulnerable road users" (VRU). Its main function is to compel drivers to observe a maximum speed limit of 30 km/h. However, urban infrastructure transformations modify traffic collision patterns and the involvement of road users, with a spatial temporal redistribution of events. This work seeks to study the effects on collision distribution resulting from the introduction of a 30 km/h zone to the Mirafiori Nord area in the city of Turin in late 2008. Collision frequencies, based on data provided by the Italian National Institute of Statistics (ISTAT), were evaluated over the period 2006-2016. Road traffic collisions involving both VRU and motorized users ("noVRU") were taken into account. Decreases in collision frequency were found for noVRU related crashes, while the VRU crash rate remained essentially unchanged with only minor fluctuations consistent with the regression to the mean phenomenon. The countermeasures, which sought to protect VRU, were however very effective for noVRU. As the effects of each structural modification spill over into neighboring areas, the analysis of collision frequency was extended to a study area greater than the one in which the 30 km/h zone was realized. In fact, due to the migration of events, the reduction in the collision frequency in the speed restricted zone was accompanied by an increase in the same frequency in the immediate surrounding area.
Curves represent the most interesting element to be analyzed when evaluating the operational and ... more Curves represent the most interesting element to be analyzed when evaluating the operational and safety effects of road geometrics. Despite the existence of several static and dynamic survey techniques, the correct identification of curves and the interpretation of spatial data from horizontal road alignment surveys still represent a challenge. The paper presents the results of an investigation into the effects of both accuracy and sampling frequency (i.e., the interval between data points) of alignment spatial data on the identification of the radius and center of curvature. In pursuit of this objective, the authors adopted an original approach consisting of the generation of dispersed spatial data points from circular arcs with known characteristics. The Least Squares, Huber and Landau methods were used to back-calculate the radius and the coordinates of the center of curvature, and to assess the effects of accuracy and interval between data points. The results obtained quantified the effects of accuracy, interval between points, radius magnitude, and length of circular arc on the identification of circular arcs. In support of future survey activities, considerations regarding the accuracy of measurements, the sampling frequency, and arc characteristics (i.e., length, radius) are discussed in the paper.
Transportation Research Record: Journal of the Transportation Research Board
Most existing roads were designed without considering the improved performance of modern vehicles... more Most existing roads were designed without considering the improved performance of modern vehicles and the new onboard technologies available for assisted driving. In addition, vehicles frequently travel at speeds that exceed the maximum considered in road design. For these reasons, the need for speed- and safety-related countermeasures (e.g., field control, mobile or fixed speed cameras, traffic calming measures) is evident. However, these countermeasures are only partially effective and the proportion of crashes that are speed-related remains significant. This investigation is aimed at the development of a new intelligent speed adaptation (ISA) system based on the available sight distance (ASD). In conditions of poor visibility, the system can (i) inform drivers when they are traveling at inappropriate speeds, or (ii) generate warning sounds to the same effect, or (iii) intervene directly and compel the vehicle to adopt the speed which is most appropriate to the particular ASD. As ...
The available sight distance (ASD) is that part of the roadway ahead which is visible to the driv... more The available sight distance (ASD) is that part of the roadway ahead which is visible to the driver, and should be of sufficient length to allow a vehicle traveling at the designated speed to stop before reaching a stationary object in its path. It is fundamental in assessing road safety of a project or on an existing road section. Unfortunately, an accurate estimation of the available sight distance is still an issue on existing roads, above all due to the lack of information regarding the as-built condition of the infrastructure. Today, the geomatics field already offers different solutions for collecting 3D information about environments at different scales, integrating multiple sensors, but the main issue regarding existing mobile mapping systems (MMSs) is their high cost. The first part of this research focused on the use of a low-cost MMS as an alternative for obtaining 3D information about infrastructure. The obtained model can be exploited as input data of specific algorithm...
Transportation Research Part F: Traffic Psychology and Behaviour, 2016
Operating speeds on roads are influenced by lighting conditions: indeed most of the driving tasks... more Operating speeds on roads are influenced by lighting conditions: indeed most of the driving tasks are influenced by visual information. In terms of supporting evidence, there is a significant volume of published research that demonstrates how safety is affected by road geometrics and environmental lighting conditions. However, only a few studies have investigated the contextual impact of these factors on driver speed behaviour, which in turn is considered one of the most important variables affecting road safety. In this paper, speed distributions have been modelled using environmental parameters related to both road geometrics and lighting conditions. To achieve this, the authors compiled a comprehensive database in which geometric characteristics, speeds, illuminance and luminance are available for both night-time and daytime conditions. The results show that average speeds and deviations from the mean are significantly affected by changes in lighting parameters for the different conditions (sunny, cloudy, and dark) considered in this study. Knowing the effects of such parameters on operating speed is fundamental for effective road management policies, especially on urban roads where, notably, the highest number of accidents occur.
The most effective way to reduce vehicle speed on urban low volume roads, such as residential str... more The most effective way to reduce vehicle speed on urban low volume roads, such as residential streets, is the installation of traffic calming systems such as speed humps and tables. In those roads in which these measures are applied, a reduction in traffic volume and accidents is generally observed, with clear benefits for pedestrians, bicyclists and residents.
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Papers by Marco Bassani