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dc.contributor.authorEl-Metwally, Mahaen_US
dc.date.accessioned2017-04-04T19:50:19Z
dc.date.available2017-04-04T19:50:19Z
dc.date.issued2010-12-06en_US
dc.identifier.otheretd-12172010-131604en_US
dc.identifier.urihttp://hdl.handle.net/10919/76921
dc.description.abstractThe fact that traffic congestion upstream of a bottleneck causes a reduction in the discharge flow rate through the bottleneck has been well documented in several empirical studies. However, what has been missing is an understanding of the causes of these empirically observed flow reductions. An identification of these causes is important in order to develop various mitigation schemes through the use of emerging technology. The concept of capacity drop can be introduced at time-independent bottlenecks (e.g. freeways) as well as time-dependent bottlenecks (e.g. signalized intersections). While to the author's knowledge no one has attempted to link these phenomena, the research presented in this thesis serves as a first step in doing so. The research uses the INTEGRATION simulation software, after demonstrating its validity against empirical data, to simulate time-independent and time-dependent bottlenecks in an attempt to characterize and understand the contributing factors to these flow reductions. Initially, the INTEGRATION simulation software is validated by comparing its results to empirically observed traffic stream behavior. This thesis demonstrates that the discharge flow rate is reduced at stationary bottlenecks at the onset of congestion. These reductions at stationary bottlenecks are not recovered as the traffic stream propagates downstream. Furthermore, these reductions are not impacted by the level of vehicle acceleration. Alternatively, the drop in the discharge flow rate caused by time-dependent bottleneck is recoverable and is dependent on the level of acceleration. The difference in behavior is attributed to the fact that in the case of a stationary bottleneck the delay in vehicle headways exceeds the losses caused by vehicle accelerations and thus is not recoverable. In the case of vehicles discharging from a backward recovery wave the dominant factor is the delay caused by vehicle acceleration and this can be recuperated as the traffic stream travels downstream.
dc.language.isoen_USen_US
dc.publisherVirginia Techen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectTime-dependent Bottlenecksen_US
dc.subjectOnset of Congestionen_US
dc.subjectCapacity Dropen_US
dc.subjectTime-independent Bottlenecksen_US
dc.titleA Study of the Capacity Drop Phenomenon at Time-Dependent and Time-Independent Bottlenecksen_US
dc.typeThesisen_US
dc.contributor.departmentCivil Engineeringen_US
dc.description.degreeM.S.en_US
thesis.degree.nameM.S.en_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeechairRakha, Hesham Ahmeden_US
dc.contributor.committeememberEl-Shawarby, Ihaben_US
dc.contributor.committeememberHobeika, Antoine G.en_US
dc.type.dcmitypeTexten_US
dc.identifier.sourceurlhttp://theses.lib.vt.edu/theses/available/etd-12172010-131604/en_US
dc.date.sdate2010-12-17en_US
dc.date.rdate2016-09-27
dc.date.adate2011-01-12en_US


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