Suchergebnisse

More than 50% of injury accidents in Spain take place on crosstown roads in urban areas. Traffic calming is an initiative to reduce the impact of traffic on local streets by lowering both the number and the severity of crashes. However, the implementation of traffic-calming devices in Spain was not standardized in the past, and no technical criteria were applied. The paper presents the methodology, results, and conclusions of an analysis specifically related to speed tables, which are flat-topped speed humps, as part of the research project MODETRA. For the research, five low-volume crosstown roads with 16 speed tables were selected to analyze drivers' behavior. Speed data were collected from a sample of more than 900 vehicles through the selected crosstown roads using Global Positioning System trackers. For each individual vehicle, a continuous speed profile along the path was obtained. The analysis showed that the minimum speed occurred when the vehicle left the traffic-calming device and the maximum deceleration occurred just before the device. Geometric characteristics of the speed tables were measured by using a digital profilometer. A wide dispersion in the geometry can be concluded. It was found that the speed reduction depended mainly on the separation between traffic-calming devices, whereas the speed over the speed tables depended crucially on the entrance-ramp slope, the speed table length, and the distance from the previous traffic control device. Also, no statistical correlations were found between speed table height and speed reduction or spot speed over the speed table. ; The authors thank the Center for Studies and Experimentation of Public Works of the Spanish Ministry of Public Works, which subsidized the research. They also thank the Infrastructure and Transportation Department, General Directorate of Public Works, Valencian Government, Spain, and the Ministry of the Interior, General Directorate of Traffic, Spain, for their cooperation during data collection. ; Moreno Chou, AT.; García ...

Traffic calming has been widely applied to urban areas in recent decades to moderate speed and traffic volume. Because most measures used are physical, a vehicle must modify its path and speed. A benefit of traffic calming is improved safety from speed reduction and traffic volume reduction. However, traffic calming has disadvantages, such as emergency response delays, traffic diversion, noise, vibrations, damage to vehicles, and discomfort. Common traffic-calming devices do not consider discomfort for drivers who achieve an appropriate calmed and safe speed. Consequently, it was necessary to develop a new traffic-calming device to moderate speed and to minimize the disadvantages of the previous devices. The Highway Engineering Research Group of the Polytechnic University of Valencia, Spain, has invented, designed, and developed a new traffic-calming device, Speed Kidney. This paper provides the objectives of the Speed Kidney, a description of the new traffic-calming device, and its geometric design. The technological development of the device is described, as are the main results from preliminary tests, implementation on a campus street, and implementation on a controlled test track. Implementation criteria are also given. The Speed Kidney is a functional, feasible, sustainable, and safe solution for traffic calming. ; The authors thank the Center for Studies and Experimentation of Public Works of the Spanish Ministry of Public Works and the Education Department, Valencian Government, Spain, which subsidized the research. The authors also thank the company Pavasal E.C. for cooperation on the implementation and the improvement of the constructive method. Finally, the test site could not have been constructed without the loan of the site from the Ministry of Public Works, Spain, and the collaboration of the company Abertis. ; García García, A.; Moreno Chou, AT.; Romero Rojas, MA. (2011). DEVELOPMENT AND VALIDATION OF SPEED KIDNEY, A NEW TRAFFIC CALMING DEVICE. Transportation Research Record. (2223):43-63. ...

Integrated land-use/transport models have five decades of history of both widely recognized successful implementations and implementations that remained far behind their originally stated goals. This paper summarizes the state of the art of integrated land-use/transport modeling and reports on findings from the Symposium for the Integration of Land-Use and Transport Models in Raitenhaslach, which is near Munich, in 2016. From these sources, the paper identifies major challenges in integrated land-use/transport modeling and proposes paths that support successful implementations. Particular attention is given to the coordination of short- and long-term decisions, the technical integration of models, microscopic versus macroscopic frameworks and appropriate levels of model complexity. The paper concludes with five themes that require further research to ensure that integrated land-use/transport models will keep up with modeling needs in the future.