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Traffic flow analysis in Ahmedabad (India)
- Source :
- Case Studies on Transport Policy. 8:215-228
- Publication Year :
- 2020
- Publisher :
- Elsevier BV, 2020.
-
Abstract
- In terms of traffic flow analysis, there are many research studies since 1935 when Bruce Douglas Greenshields introduced traffic flow theory with traffic density and vehicle speed using photographic measurement methods for the first time. There are several theoretical proposals followed by Greenshields, such as Greenberg (1959) , Underwood (1961) etc. In these studies, there are several limitations like, particular expressways, time period to be measured and so on. While Greenshields’ model is not perfect, it is fairly accurate and relative simple. Therefore Greenshields’ model is widely used in the traffic flow analysis. In advanced countries Europe, United State of America and Japan, there are several variations for their analysis and certain confidence based on Greenshields’ model. However there is quite few traffic flow analysis in developing countries because of their difficulty for measuring traffic condition and lack of infrastructure system for road operation. The purpose of this study is the first time to analyze actual traffic flow based on more than one month collecting traffic date in Ahmedabad city of Gujarat state India. In order to analyze traffic data quantitatively in Ahmedabad city, we are able to collect actual traffic flow data. However the data is spread out widely which is most unlikely in the advanced countries. After creating traffic flow with measured data such as traffic density (k) to traffic volume (q) and traffic density (k) to speed (v), there are clear boundary line each traffic characteristic which divides from data existence area and no existence area in every traffic flow characteristics. The Data Envelopment Analysis (DEA) allows to make traffic characteristics of each roads uniquely when the theoretical traffic flow equations fit along with those Envelopment lines. Once the traffic flow equation is fixed, we are able to get traffic parameters such as free flow speed (vf), jam traffic density (kj) etc. In order to understand traffic congestion, we create speed ratio which is average speed (vave) to free speed (vf) which makes generic value for comparing traffic condition among measured roads. As the result of DEA, we have the traffic flow equation for each road as the basic traffic flow characteristics and understand inside of those Envelopment line is traffic congestion. And speed ratio parameter under 0.65 shows congested condition by real traffic condition monitoring. This phenomena reminds some similarity of the parallel flat plates viscous fluids model characteristics. The flow speed ratio between average flow speed to maximum flow speed becomes two third provides threshold between turbulent flow and viscous flow. This study is the beginning of developing country with quantitative analysis by DEA and helps the understanding traffic flow characteristics.
- Subjects :
- 050210 logistics & transportation
Data collection
Turbulence
Computer science
05 social sciences
Geography, Planning and Development
Maximum flow problem
0211 other engineering and technologies
021107 urban & regional planning
Transportation
02 engineering and technology
Traffic flow
Urban Studies
Transport engineering
Traffic congestion
Flow velocity
0502 economics and business
Line (geometry)
Data envelopment analysis
Subjects
Details
- ISSN :
- 2213624X
- Volume :
- 8
- Database :
- OpenAIRE
- Journal :
- Case Studies on Transport Policy
- Accession number :
- edsair.doi...........fa276aacc0c6c20494d095ea1647cb0a