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Last edit of __final format approved LW 5-6-19.pdf (1.6 MB)
ETD Abstract Container
Abstract Header
Comparative Analysis of Roundabout Capacity Analysis Methods
Author Info
Alqahtani, Abdullah Ayed F.
ORCID® Identifier
http://orcid.org/0000-0002-0244-7776
Permalink:
http://rave.ohiolink.edu/etdc/view?acc_num=dayton1557252181941848
Abstract Details
Year and Degree
2019, Master of Science (M.S.), University of Dayton, Civil Engineering.
Abstract
According to the Washington State Department of Transportation (WSDOT), the use of roundabouts has been increasing due to its numerous benefits. Compared to other types of intersection (conventional) controls, a roundabout improves traffic safety, reduces delays, lessens the severity of crashes, improves traffic flow, and minimizes maintenance costs. The Federal Highway Administration (FHWA) report that in some previous study findings the injury and fatality crashes were reduced by 78-82% after converting signalized intersections to roundabouts. This study used data from the City of Fairborn, Ohio, for a project where they were preparing to replace a 50-years old signalized intersection (at Kauffman Avenue and Colonel Glenn Highway) with a modern roundabout. This signalized intersection experienced 18 crashes between 2013 and 2015. The modern roundabout was scheduled to be constructed in 2019 by the City of Fairborn, and it was designed with three legs (similar to the existing intersection layout), with three entries, three exits, and one circulating lane. Two software programs were used in this study, which are RODEL and Highway Capacity Software (HCS7), and two manual methods were also used, which are 2010 Federal Highway Administration method (Roundabouts: An Informational Guide) and 2016 Highway Capacity Manual (HCM 6). The main aim of this study was to compare capacity analysis results to the same data inputs among all methods. The results from this study are helpful in explaining the performance of each method and provide an understanding of analyzing roundabout capacity. The comparative results for each method include capacity, volume-to-capacity ratio, control delay, level of service (LOS), 95th percentile queue length for each approach/lane, and the entire intersection control delay and LOS. The results show that RODEL (geometric model) predicted the largest capacity, the smallest volume-to-capacity, the lowest delay, the best LOS, the shortest 95% queue length, and the lowest delay and best LOS for entire intersection. This supports the conclusions of previous studies. The FHWA 2010 results were quite the opposite; estimated the lowest capacity for the same traffic and geometric inputs, largest queues, delays and volume-to-capacity ratio. The results from HCS7, 2016 HCM (HCM 6), 2010 FHWA and RODEL (HCM 2016 model) were similar because they use the same methodology. HCS7 software automates the HCM6 methodologies.
Committee
Deogratias Eustace (Advisor)
Pages
90 p.
Subject Headings
Civil Engineering
;
Transportation
;
Transportation Planning
Keywords
Roundabout Capacity
;
Roundabout Capacity Methods
;
RODEL Software
;
HCM 2016
;
HCS7 Software
;
Roundabout Capacity Analysis
;
Roundabout Performance
;
control delay and level of service of roundabouts
;
roundabout queue length
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Refworks
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Citations
Alqahtani, A. A. F. (2019).
Comparative Analysis of Roundabout Capacity Analysis Methods
[Master's thesis, University of Dayton]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1557252181941848
APA Style (7th edition)
Alqahtani, Abdullah.
Comparative Analysis of Roundabout Capacity Analysis Methods .
2019. University of Dayton, Master's thesis.
OhioLINK Electronic Theses and Dissertations Center
, http://rave.ohiolink.edu/etdc/view?acc_num=dayton1557252181941848.
MLA Style (8th edition)
Alqahtani, Abdullah. "Comparative Analysis of Roundabout Capacity Analysis Methods ." Master's thesis, University of Dayton, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1557252181941848
Chicago Manual of Style (17th edition)
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Document number:
dayton1557252181941848
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Copyright Info
© 2019, all rights reserved.
This open access ETD is published by University of Dayton and OhioLINK.