3 research outputs found
Modeling Link-level Road Traffic Resilience to Extreme Weather Events Using Crowdsourced Data
Climate changes lead to more frequent and intense weather events, posing
escalating risks to road traffic. Crowdsourced data offer new opportunities to
monitor and investigate changes in road traffic flow during extreme weather.
This study utilizes diverse crowdsourced data from mobile devices and the
community-driven navigation app, Waze, to examine the impact of three weather
events (i.e., floods, winter storms, and fog) on road traffic. Three metrics,
speed change, event duration, and area under the curve (AUC), are employed to
assess link-level traffic change and recovery. In addition, a user's perceived
severity is computed to evaluate link-level weather impact based on
crowdsourced reports. This study evaluates a range of new data sources, and
provides insights into the resilience of road traffic to extreme weather, which
are crucial for disaster preparedness, response, and recovery in road
transportation systems
Design of Drainage Downspouts Systems over a Road Embankment
[EN] Numerous studies have examined the complex relationship between factors like embankment downspout spacing, height, slope, and rainfall characteristics in the quest to find the best spacing for embankment downspouts. Defining the correct spacing between road drainage elements is of utmost importance in minimizing water flow on roadways. This paper presents a methodology based on numerical methods for the design of road drainage systems using the Iber model. The objective of the work is to propose a tool and criteria for analyzing the hydraulic behavior of runoff on highways, determine the appropriate drainage behavior, and apply the methodology in a case study. This case study is based on a straight highway section with slopes up to 5%, according to Spanish road design regulations. Different dimensions are considered for the chute, drainage channel, collection nozzle, and downspout over the embankment. Tests are carried out to evaluate the separation between downspouts, the longitudinal slope, and the size of the nozzles. The results show the suitable hydraulic performance of the model, besides providing the absorption capacity of each downspout. The influence of the nozzle size, the slope, and the width of the causeway on the draughts and velocities is analyzed. The influence of downspout spacing and nozzle type on road drainage design is determined. In summary, this article presents a methodology and criteria for the design of road drainage systems and shows the results obtained in a case study using the Iber model. The results help in understanding the influence of different variables on the hydraulic behavior of road runoff and provide relevant information for proper drainage design.Aranda Domingo, JÁ.; Sánchez-Juny, M.; Sanz-Ramos, M.; Beneyto, C. (2023). Design of Drainage Downspouts Systems over a Road Embankment. Water. 15(20):1-19. https://doi.org/10.3390/w15203529119152
Uma simulação para Sistemas de Gerenciamento do Tráfego com Tratamento do Clima
Trabalho de Conclusão de Curso (graduação)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2019.O desenvolvimento de capacidades de cooperação entre veículos conectados (CV) é indispen-
sável para o futuro de transportes terrestres sobre redes viárias com infraestruturas cada vez
mais populadas e inteligentes. O conhecimento de métodos de predição de tráfego e de es-
tratégias de controle de trânsito é essencial no desenvolvimento de aplicações que auxiliem os
condutores em seus percursos diários. Em geral o clima afeta o trânsito criando efeitos adversos
sobre a via, tais como redução da visibilidade, diminuição da fricção do pavimento, bem como
ameaça ao desempenho do veículo (e.g., , tração, estabilidade e manobrabilidade). O uso de
ferramentas de simulação é a melhor maneira de se tratar alterações repentinas nas condições
da rede viária devido ao surgimento de eventos de precipitação extrema. Contudo, a maioria
das soluções de Sistema de Gerenciamento de Tráfego (SGT) atuais não consideram os efeitos
das condições adversas de tempo. Nesse contexto, o trabalho presente estuda os impactos de
eventos de precipitação extrema sobre o fluxo regular de veículos num cenário urbano típico.
É proposto um mecanismo de ocorrência de eventos de precipitação para um SGT completa-
mente distribuído e baseado em Vehicular ad hoc Networks (VANET). Resultados da simulação
mostraram que mesmo para uma situação restrita de chuva forte, quando comparada ao registro
original de mobilidade dos veículos (OVMT), apresentam um aumento drástico na variabilidade
dos dados relativos a mensagens duplicadas, número de mensagens recebidas e tempo de espera
acumulado. O estudo pretende ajudar na compreensão das necessidades na disciplina de SGT
com Tratamento do Clima (WRTM) para fornecer alertas de segurança a veículos autônomos e
conectados (CAV).The development of cooperation capabilities between connected vehicles (CV) seems to be in-
dispensable for the future of land-based transports over road networks with increasingly more
populated and intelligent infrastructures. The knowledge around methods of traffic prediction
and transit control strategies is essential in the development of applications which aim to aid
drivers in their daily routes. Generally, weather impacts the transit by generating adverse ef-
fects on the roads, like reduced visibility, decreasing pavement friction, as well as influencing
driver behaviour and threating vehicle performance (e.g., traction, stability, maneuverability).
The use of simulation tools is the best way to address sudden changes in the road network con-
ditions due to the emergence of inclement weather. In this context, the present work studies
the impacts of extreme precipitation events on regular vehicle flow in a typical urban scenario.
A mechanism of precipitation occurrence is proposed for a fully-distributed and VANET-based
Traffic Management System (TMS). Simulation results shows that, even for the occasion of a
constricted heavy rain, when compared to the original vehicle mobility trace (OVMT), presents
a drastic increase in the variability of the data related to duplicated messages, total messages
received and accumulated waiting travel time. The research intends to be helpfull in under-
standing Weather-Responsive Traffic Management System (WRTMS) needs for the offering of
safety alerts to connected and automated vehicles (CAV)