CARACTERIZACIÓN Y MODELIZACIÓN DE LA VELOCIDAD DE OPERACIÓN EN CARRETERAS CONVENCIONALES A PARTIR DE LA OBSERVACIÓN NATURALÍSTICA DE LA EVOLUCIÓN DE VEHÍCULOS LIGEROS

Los tres principales factores concurrentes de la siniestralidad son: el conductor, el vehículo y la infraestructura. Este último es el causante, en mayor o menor medida, del 30 % de los accidentes en carretera. Una de las principales razones relacionadas con la infraestructura es la baja consistencia del diseño geométrico, que produce que la geometría de la vía no se ajuste a las expectativas de los conductores y, por tanto, que estos puedan verse sorprendidos ante ciertas configuraciones de la misma, dando como resultado un incremento en el número de accidentes. Los criterios más utilizados para la determinación de la consistencia están basados en la evaluación del perfil de velocidad de operación, identificada como el percentil 85 de la distribución de velocidades de vehículos circulando en condiciones de flujo libre en un tramo de carretera. Esta variable puede obtenerse a partir de mediciones durante la fase de explotación de una carretera. Sin embargo, tanto en la fase de planeamiento como en la de proyecto, únicamente puede estimarse. Para ello, se utilizan los modelos de estimación de la velocidad de operación a partir de las características geométricas del trazado de la carretera. En el presente trabajo de investigación, se han calibrado diferentes modelos que, mediante una serie de reglas de construcción, permiten la estimación del perfil continuo de velocidad de operación en un tramo de carretera convencional, a partir de sus características geométricas. Para ello, se ha desarrollado una nueva metodología de toma de datos. Esta metodología se basa en los datos registrados mediante dispositivos GPS instalados en vehículos de conductores ajenos a la investigación. Los resultados de la toma de datos consisten en los perfiles continuos de velocidad de operación individuales de cada conductor y en su trayectoria. Su tratamiento permite la restitución de la geometría del trazado de la carretera y la obtención del perfil continuo de velocidad de operación .......Pérez Zuriaga, AM. (2012). CARACTERIZACIÓN Y MODELIZACIÓN DE LA VELOCIDAD DE OPERACIÓN EN CARRETERAS CONVENCIONALES A PARTIR DE LA OBSERVACIÓN NATURALÍSTICA DE LA EVOLUCIÓN DE VEHÍCULOS LIGEROS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16701Palanci

Comparación de la velocidad de paso por curva en trazados carreteros y ferroviarios

En este documento se realiza una comparativa entre las velocidades máximas de paso por curva, tanto para vehículos ferroviarios de diferentes tipos como para vehículos de carretera. Esta comparativa sirve para realizar una serie de reflexiones sobre la homogeneidad ¿o falta de ella¿ a la hora de establecer los criterios de confort en un modo u otro. También permite comparar en qué rangos de radios de curvaturas, como medida indirecta de la adaptabilidad al territorio, resulta más atractivo cada modo de transporte.Salvador Zuriaga, P.; Villalba Sanchis, I.; Pérez Zuriaga, AM. (2019). Comparación de la velocidad de paso por curva en trazados carreteros y ferroviarios. http://hdl.handle.net/10251/122739DE

Operational effectiveness of passing zones depending on their length and traffic volume

Most studies on two-lane highway operations have focused on the percentage of following vehicles or the adjustment of the Highway Capacity Manual (HCM) procedure to local data. The HCM proposes the length of no-passing zones as a model parameter; however, the distribution and characteristics of passing zones are not addressed. In fact, only a few studies on the expected number of passes in a passing zone have been carried out. This research presents an analysis of the effectiveness of passing zones in terms of their length and traffic volume. Data were collected from four passing zones on a rural highway in Spain. The two-way traffic volumes ranged from 100 to 900 vehicles per hour (vph), and the passing zone lengths ranged from 265 to 1,270 m. More than 1,600 passing maneuvers were recorded. The operational effectiveness of the passing zones was obtained from the passing frequency and the passing rate. The results indicated that the longer the passing zone, the higher the passing frequency; however, the results stabilized with lengths above 1,100 m. Balanced flows with two-way traffic volumes between 600 and 700 vph optimized the number of passes. Nevertheless, the increase in the passing frequency with the traffic volume was lower than with the increase in following vehicles. The results were validated with data from another 12 passing zones. Finally, HCM adjustments based on the percentage of no-passing zones did not reliably represent the effectiveness of passing zones. Therefore, the effectiveness of every passing zone should be considered, and adjustment factors should be modified to maximize the passing opportunities for traffic volumes between 600 and 700 vph.The authors thank the Spanish Ministry of Science and Innovation, which subsidized the research project, and the Spanish Ministry of Public Works for its collaboration during the field study.Moreno Chou, AT.; Llorca Garcia, C.; García García, A.; Pérez Zuriaga, AM. (2013). Operational effectiveness of passing zones depending on their length and traffic volume. Transportation Research Record. (2395):57-65. doi:10.3141/2395-07S57652395Romana, M. G. (1999). Passing Activity on Two-Lane Highways in Spain. Transportation Research Record: Journal of the Transportation Research Board, 1678(1), 90-95. doi:10.3141/1678-12Al-Kaisy, A., & Freedman, Z. (2010). Estimating Performance on Two-Lane Highways. Transportation Research Record: Journal of the Transportation Research Board, 2173(1), 72-79. doi:10.3141/2173-09Al-Kaisy, A., & Karjala, S. (2010). Car-Following Interaction and the Definition of Free-Moving Vehicles on Two-Lane Rural Highways. Journal of Transportation Engineering, 136(10), 925-931. doi:10.1061/(asce)te.1943-5436.0000148Al-Kaisy, A., & Durbin, C. (2011). Platooning on Two-lane Two-way Highways: An Empirical Investigation. Procedia - Social and Behavioral Sciences, 16, 329-339. doi:10.1016/j.sbspro.2011.04.454Gattis, J. L., Alguire, M. S., Townsend, K., & Rao, S. (1997). Rural Two-Lane Passing Headways and Platooning. Transportation Research Record: Journal of the Transportation Research Board, 1579(1), 27-34. doi:10.3141/1579-04Dixon, M. P., Sarepali, S. S. K., & Young, K. A. (2002). Field Evaluation of Highway Capacity Manual 2000 Analysis Procedures for Two-Lane Highways. Transportation Research Record: Journal of the Transportation Research Board, 1802(1), 125-132. doi:10.3141/1802-15Polus, A., & Cohen, M. (2009). Theoretical and Empirical Relationships for the Quality of Flow and for a New Level of Service on Two-Lane Highways. Journal of Transportation Engineering, 135(6), 380-385. doi:10.1061/(asce)0733-947x(2009)135:6(380)Rozenshtein, S., Polus, A., & Cohen, M. (2012). Models for Estimating Drivers following on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 2286(1), 68-75. doi:10.3141/2286-08Al-Kaisy, A., & Durbin, C. (2008). Evaluating new methodologies for estimating performance on two-lane highways. Canadian Journal of Civil Engineering, 35(8), 777-785. doi:10.1139/l08-020Llorca, C., & García, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record: Journal of the Transportation Research Board, 2262(1), 42-51. doi:10.3141/2262-0

Analysis of the consequences of car to micromobility user side impact crashes

Mobility has changed in recent years in cities worldwide, th.anks to tb.e strong rise in vehicles of micromobility. Bicycle riding is the most widespread micromobility transport mode, followed by stand-up electric scooters (e-scooters). This increase in its use has also led to an increase in related crashes. Both cyclists and e-scooter riders are vulnerable road users and are lik.ely to sustain severe injuries in crashes, especially with motor vehicles. The crashes consequences involving cyclists and other micromobility users have already investigated using numerical simulation software, such as MADYMO and PC-Crash. Most of them have been focused on bicycles and electric bicycles, whereas only few of tbem have analyzed e-scooter crashes consequences. Posirisuk: et al. [1] carried out a computational prediction ofhead-ground impact k:inematics :in e-scooter falls. Ptak et al. [2] analyzed the e-scooter user kinematics after a crash against SUV when the e-scooter chives into the sidefront of tbe vehicle, a side B-pillar crash and a frontal impact initiated by tbe e-scooter to tbe front-end of the vehicle. However, they did not study the consequ.ences of a car to e-scooter side impact crashes. Xu et al. [3] did study these crashes but considering electric self-balancing scooters that are less widespread than e-scooters. Current study focuses on the consequences of a car to micromobility user (cyclist and e-scooter rider) side impact crashes. The analysis is based on numerical simulations with PC-Crash software

Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain

[EN] Passing is one of the most complex driving maneuvers performed on two-lane rural roads and has important effects on road safety and traffic operation. Passing is affected by driving behavior, road geometry, traffic volume, and traffic composition as well as external factors. Research was developed to compare the passing process under daytime and nighttime conditions. An experimental method was designed to collect video data of passing maneuvers on a two-lane rural road segment located near Valencia, Spain. Two methods were used: (a) external observations of four passing zones with six video cameras and (b) an instrumented vehicle equipped with video cameras and laser rangefinders, driven slightly below the operating speed along a segment of the same road so it would be passed by other vehicles. A total of 291 maneuvers were observed, up to 20% of which were at night. Macroscopic analysis results indicated that approximately 17% of passes were at night, even though passing frequency and passing demand decreased at night. Also, the behaviors of individual drivers who passed other vehicles were different at night and during the day. Maneuvers limited by the presence of an opposing vehicle were performed more quickly at night, even if the accepted gaps were longer. In this case, a more difficult perception of distances to opposing vehicles and of vehicle speeds explained the differences. In contrast, maneuvers limited by sight distance (without a visible opposing vehicle) were slower at night. This observation matched a traditional hypothesis: passing at night is safer because the headlights of an opposing vehicle allow a driver to anticipate the vehicle's position before it becomes visible.The authors thank the Spanish Ministry of Economy and Competitiveness for subsidizing the research project as well as the Spanish Ministry of Public Works and the Spanish General Traffic Directorate for collaboration during the field study.Llorca Garcia, C.; Moreno Chou, AT.; García García, A.; Pérez Zuriaga, AM. (2013). Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain. Transportation Research Record. (2358):3-11. doi:10.3141/2358-01S311235

Factors Influencing the Pedestrian Injury Severity of Micromobility Crashes

[EN] The growth of micromobility transport in cities has created a new mobility paradigm, but this has also resulted in increased traffic conflicts and collisions. This research focuses on understanding the impacts of micromobility vehicles on pedestrian injury severity in urban areas of Spain between 2016 and 2021. The Random Forest classification model was used to identify the most significant factors and their combinations affecting pedestrian injury severity. To address the issue of unbalanced data, the synthetic minority oversampling technique was employed. The findings indicate that pedestrians' age, specifically those 70 years or older, is the most important variable in determining injury severity. Additionally, collisions at junctions or on weekends are associated with worse outcomes for pedestrians. The results highlight the combined influence of multiple factors, including offenses and distractions by micromobility users and pedestrians. These factors are more prevalent among younger micromobility users and those riding for leisure or on weekends. To enhance micromobility road safety and reduce pedestrian injuries, separating micromobility traffic from pedestrian areas is recommended, restricting micromobility vehicle use on sidewalks, providing training and information to micromobility users, conducting road safety campaigns, increasing enforcement measures, and incorporating buffer zones in bike lanes near on-street parking.This research is part of the research project PID2019-111744RB-I00, funded by MCIN/AEI/10.13039/501100011033. Likewise, this research has been partially funded by the European Union-Next GenerationEU (RD 289/2021), thanks to the granting of a "Margarita Salas" grant to Almudena Sanjurjo (UP2021-035), researcher at the Universidad Politecnica de Madrid (UPM), to carry out astay at the Universitat Politecnica de Valencia (UPV)Sanjurjo-De-No, A.; Pérez Zuriaga, AM.; García García, A. (2023). Factors Influencing the Pedestrian Injury Severity of Micromobility Crashes. Sustainability. 15(19):1-17. https://doi.org/10.3390/su151914348117151

Analysis of Overtaking Maneuvers to Cycling Groups on Two-Lane Rural Roads using Objective and Subjective Risk

[EN] In Spain, the presence of cyclists' groups riding on two-lane rural roads in a single file or in parallel line is growing. The number of overtaking maneuvers to them is also increasing. This is one of the most dangerous interactions between motor vehicles and bicycles. However, the risk of these maneuvers has not been analyzed in depth. This research analyzes the objective and subjective risk of overtaking maneuvers to cyclists' groups. During this maneuver, the motorized vehicle overtakes the bicycles with a certain speed and lateral distance. These are the surrogate measures used to analyze the objective risk, whereas the subjective risk was analyzed based on the subjective risk perception that 10 cyclists riding instrumented bicycles (in different group configurations) indicated when every motor vehicle overtook them. Results show that the cyclists most exposed to the overtaking maneuver are those at the front and at the rear of the group. In relation to the configuration, the risk is higher in parallel lines, as the lateral clearance is lower compared with a single line. It is even higher when the overtaking maneuver is flying, which is usually performed at higher speeds and lower lateral clearance. The subjective risk perception increases with higher speed and lower lateral clearance, and is higher at the rear positions. Overtaking in which lateral distance is less than 1.5 m is perceived as the riskiest. These results provide scientific recommendations to enhance safety for cyclists' groups, and to integrate cycling with vehicular traffic on two-lane rural roadsThe author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The study presented in this paper is part of the research project titled "Road safety countermeasures for two-lane rural roads with group of cyclists (Safe4Bikes)'' (SPIP2017-02280), subsidized by the Direccion General de Trafico (General Directorate of Traffic) of Spain. DocumentLópez-Maldonado, G.; Pérez Zuriaga, AM.; Moll Montaner, S.; García García, A. (2020). Analysis of Overtaking Maneuvers to Cycling Groups on Two-Lane Rural Roads using Objective and Subjective Risk. Transportation Research Record. 2674(7):148-160. https://doi.org/10.1177/0361198120921169S14816026747Boufous, S., de Rome, L., Senserrick, T., & Ivers, R. (2012). Risk factors for severe injury in cyclists involved in traffic crashes in Victoria, Australia. Accident Analysis & Prevention, 49, 404-409. doi:10.1016/j.aap.2012.03.011Chaurand, N., & Delhomme, P. (2013). Cyclists and drivers in road interactions: A comparison of perceived crash risk. Accident Analysis & Prevention, 50, 1176-1184. doi:10.1016/j.aap.2012.09.005Dozza, M., Schindler, R., Bianchi-Piccinini, G., & Karlsson, J. (2016). How do drivers overtake cyclists? Accident Analysis & Prevention, 88, 29-36. doi:10.1016/j.aap.2015.12.008Walker, I., Garrard, I., & Jowitt, F. (2014). The influence of a bicycle commuter’s appearance on drivers’ overtaking proximities: An on-road test of bicyclist stereotypes, high-visibility clothing and safety aids in the United Kingdom. Accident Analysis & Prevention, 64, 69-77. doi:10.1016/j.aap.2013.11.007Dozza, M., & Werneke, J. (2014). Introducing naturalistic cycling data: What factors influence bicyclists’ safety in the real world? Transportation Research Part F: Traffic Psychology and Behaviour, 24, 83-91. doi:10.1016/j.trf.2014.04.001Chapman, J. R., & Noyce, D. A. (2012). Observations of Driver Behavior during Overtaking of Bicycles on Rural Roads. Transportation Research Record: Journal of the Transportation Research Board, 2321(1), 38-45. doi:10.3141/2321-06Llorca, C., Angel-Domenech, A., Agustin-Gomez, F., & Garcia, A. (2017). Motor vehicles overtaking cyclists on two-lane rural roads: Analysis on speed and lateral clearance. Safety Science, 92, 302-310. doi:10.1016/j.ssci.2015.11.005Trenchard, H., Richardson, A., Ratamero, E., & Perc, M. (2014). Collective behavior and the identification of phases in bicycle pelotons. Physica A: Statistical Mechanics and its Applications, 405, 92-103. doi:10.1016/j.physa.2014.03.002Debnath, A. K., Haworth, N., Schramm, A., Heesch, K. C., & Somoray, K. (2018). Factors influencing noncompliance with bicycle passing distance laws. Accident Analysis & Prevention, 115, 137-142. doi:10.1016/j.aap.2018.03.01

Los firmes en carreteras: características generales y funciones

El firme de la carretera constituye la parte correspondiente a la superestructura de la carretera. En este artículo se presentan los conceptos generales sobre firmes de carreteras, así como cuáles son sus funciones y qué materiales los constituyen.López Maldonado, G.; Pérez Zuriaga, AM. (2020). Los firmes en carreteras: características generales y funciones. http://hdl.handle.net/10251/142221DE

Driver behavior when overtaking cyclists riding in different group configurations on two-lane rural roads

[EN] The presence of cyclists on Spanish rural roads is ever increasing and currently frequent, and thus becoming a serious safety concern. In rural environments, the risk of a crash is higher than in rural areas. The main cause is the higher speed of motor vehicles during overtaking manoeuvres. This manoeuvre is especially challenging when cyclists ride in groups as they may change size, length, shape, and speed along their route. These variables and those related to road cross-section can influence driver behaviour when overtaking a group of cyclists. To study this, instrumented bicycles were used to ride along five road segments with different geometric and traffic characteristics. Cyclists rode individually and in groups. Overtaking was evaluated by analysing the lateral distance, the speed, and other characteristics of the manoeuvre. Wider roads presented higher lateral clearances and overtaking speeds. Narrower roads had a high opposing lane invasion but a high level of compliance with the minimum lateral clearance. A higher clearance and lower speed of overtaking vehicles was registered when cyclists rode in line. Compliance with the 1.5 m clearance depended on the group configuration, being higher when cyclists rode in line. However, overtaking cyclists riding two abreast presented more accelerative manoeuvres, especially on narrow roads.This research is part of the research project TRA2016-80897-R, funded by MCIN/AEI/10.13039/501100011033 and the research project SPIP2017-02280, funded by the General Directorate of Traffic of Spain.Pérez Zuriaga, AM.; Moll Montaner, S.; López-Maldonado, G.; García García, A. (2021). Driver behavior when overtaking cyclists riding in different group configurations on two-lane rural roads. International Journal of Environmental research and Public Health (Online). 18(23):1-18. https://doi.org/10.3390/ijerph182312797S118182

Deterioros en pavimentos urbanos

En este artículo se presentan las diferentes tipologías de deterioros o daños que habitualmente se manifiestan en pavimentos flexibles, semiflexibles y semirrígidos urbanos, así como las actividades destinadas a su rehabilitación y mantenimiento.Llopis Castelló, D.; Pérez Zuriaga, AM. (2020). Deterioros en pavimentos urbanos. http://hdl.handle.net/10251/139865DE