A Macroscopic Fundamental Diagram for Spatial Analysis of Traffic Flow: A Case Study of Nyeri Town, Kenya
American Journal of Civil Engineering
Volume 3, Issue 5, September 2015, Pages: 150-156
Received: Sep. 1, 2015;
Accepted: Sep. 21, 2015;
Published: Oct. 22, 2015
Views 5802 Downloads 249
Lekariap Edwin Mararo, Department of Civil, Construction and Environmental Engineering, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Abiero Gariy, Department of Civil, Construction and Environmental Engineering, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Mwatelah Josphat, Department of Geomatic Engineering and Geospatial Information Systems, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Traffic flow analysis is an essential component of a town’s traffic and transport systems since these flows could, and often do lead to the occurrence of congestion on our roads.Traffic congestion is a growing problem in Nyeri, Kenya, resulting from rapidly increasing population and the crowding of motorized traffic onto a limited street network. This research performed spatial analysis of traffic flows on some road links in Nyeri town. On those selected road links it also established fundamental traffic flow models and derived the flow characteristics associated with traffic operations in Nyeri town, determined the characteristics of a Macroscopic Fundamental Diagram (MFD) for Nyeri town and assessed to determine whether it is a property of the network infrastructure and control or of the travel demand. In this research, MetroCount Vehicle Classifier was used to collect traffic intensity and velocity data at different locations of the network over certain durations and at the same period between January 2015 and February 2015. The analysis of the data was performed by the MetroCount Traffic Executive MCReport. The MFD resulting from the study served as a road network performance indicator, which tells the performance levels of the town in general, in terms of traffic flow. The research was used to determine the capacity of the road network and the level of congestion in different links thereby determining the adequacy of the network. The speeds in Nyeri town are moderate, however, low and high speeds occur occasionally and the volumes of traffic in Nyeri town are not high hence congestions are rarely experienced. The results of this research study are anticipated to better traffic management, and also improve mobility and accessibility in Nyeri town.
Lekariap Edwin Mararo,
A Macroscopic Fundamental Diagram for Spatial Analysis of Traffic Flow: A Case Study of Nyeri Town, Kenya, American Journal of Civil Engineering.
Vol. 3, No. 5,
2015, pp. 150-156.
J. Williams. Macroscopic flow models. Traffic Flow Theory. Washington, DC: US Federal Highway Administration, 1996, pp 6 - 1.
G. Weisbrod, D. Vary, et al.” Measuring economic costs of urban traffic congestion to business. Transportation Research Record,” Journal of the Transportation Research Board 1839 (1): 98 - 106, 2003.
J. Rodrigue, C. Comtois, et al.” The geography of transport systems. London/New York. Salau, T. (1999). Spatial analysis of urban road system: A study of abeokuta. I. Transport Dev." Initiatives, vol. 1: 13 - 24, 2005.
N. Gartner, C. Messer, et al.” Traffic flow theory: A state of the art report." Transportation Research Board, 1992.
C. O'Flaherty, and M. Bell,” Transport planning and traffic engineering, John Wiley & Sons Inc, 1997.
Y. Yin, and H. Ieda,”Optimal improvement scheme for network reliability. Transportation Research Record,” Journal of the Transportation Research Board, vol. 1783 (1), 2002, 1 - 6.
L. Dimitriou, T. Tsekeris, et al.” Evolutionary game - theoretic model for performance reliability assessment of road networks” 2007.
A. Sumalee, and D. Watling,” Travel time reliability in a network with dependent link modes and partial driver response,” Journal of the Eastern Asia Society for Transportation Studies, vol. 5, 2003, pp 1686 - 1701.
A. Ang, and W. Tang,” Probability Concepts in Engineering Planning and Design,” Vol. II Decision, Risk, and Reliability, John Wiley & Sons, NY, 1990."
B. Green shields,” A study of traffic capacity. Proceedings of Highway Research Board” 1935.
L. Muñoz,” Macroscopic modeling and identification of freeway traffic flow,” PhD Thesis, University Of California, 2004.
V. Dixit, and E. Radwan,”Strategies to improve dissipation into destination network using macroscopic network flow models." Manuscript prepared for Symposium on the Fundamental Diagram: 75 years (“Green shields 75” Symposium),” 2007.
L. Edie,” Discussion of traffic stream measurements and definitions”. Proceedings of the Second International Symposium on the Theory of Traffic Flow, 1963.
D. Gazis,”Traffic Science,” Wiley – Inter science, 1974.
J. Wardrop,”Road Paper. Some theoretical aspects of road traffic research,” Proceedings of the Institution of Civil Engineers, Thomas Telford - ICE Virtual Library, 1952.
R. Smeed,”Traffic studies and urban congestion,” Journal of Transport Economics and Policy, vol. 2, issue 1, 1968, pp 33 - 70.
C. Daganzo,”Urban gridlock: Macroscopic modeling and mitigation approaches,” Transportation Research Part B41, issue 1, 2007, pp 49 - 62.
N. Geroliminis,” A Macroscopic Fundamental Diagram of Urban Traffic: Recent Findings,” Prepared for the Symposium on the Fundamental Diagram: 75 years, Woods Hole, Massachusetts, 8 - 10 July 2008.
N. Geroliminis, and C. Daganzo,”Existence of urban - scale macroscopic fundamental diagrams: Some experimental findings,” Transportation Research Part B42, issue 9, (2008). pp 759 - 770.