{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/139941"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/139941","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Evaluating the Operational Performance of St. Augustine U-turn Interchange (SUTI)","abstract":"This study evaluates the operational performance of a novel median U-turn interchange—St. Augustine U-turn interchange (SUTI)—as an alternative to a conventional median U-turn on arterial interchange (MUTAI) and four other existing service interchanges. The research integrates two analytical stages: Critical Lane Volume (CLV) analysis using the Highway Capacity Manual (7th Edition), and microsimulation analysis using PTV VISSIM with travel time and maximum queue lengths as the primary measures of effectiveness (MOEs). The simulation is conducted over ten random seeds per scenario to assess all the interchanges under various traffic demands, turning movement proportions, and traffic distributions. The results indicate that the new SUTI interchange required the lowest average cycle lengths to achieve the lowest volume-to-capacity (v/c) ratios, the second-best mean travel times, and the shortest mean maximum queue lengths across various demand scenarios. The conflict-point analysis revealed a reduction in conflict points when compared with conventional diamond interchanges. Overall, the SUTI and diverging diamond (DDI) interchange showed similar results. The new median U-turn design of the SUTI interchange demonstrates a significant improvement in travel time compared to the conventional MUTAI interchange.","abstract_html":"This study evaluates the operational performance of a novel median U-turn interchange—St. Augustine U-turn interchange (SUTI)—as an alternative to a conventional median U-turn on arterial interchange (MUTAI) and four other existing service interchanges. The research integrates two analytical stages: Critical Lane Volume (CLV) analysis using the Highway Capacity Manual (7th Edition), and microsimulation analysis using PTV VISSIM with travel time and maximum queue lengths as the primary measures of effectiveness (MOEs). The simulation is conducted over ten random seeds per scenario to assess all the interchanges under various traffic demands, turning movement proportions, and traffic distributions. The results indicate that the new SUTI interchange required the lowest average cycle lengths to achieve the lowest volume-to-capacity (v/c) ratios, the second-best mean travel times, and the shortest mean maximum queue lengths across various demand scenarios. The conflict-point analysis revealed a reduction in conflict points when compared with conventional diamond interchanges. Overall, the SUTI and diverging diamond (DDI) interchange showed similar results. The new median U-turn design of the SUTI interchange demonstrates a significant improvement in travel time compared to the conventional MUTAI interchange.","abstract_has_math":false,"creators":["Dixit, Kushan Jatinbhai"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Civil Engineering","degree_department":"Civil and Environmental Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":["Trani, Antonio A."],"committee_members":["Katz, Bryan J.","Flintsch, Gerardo W."],"year":2025,"date_issued":"2025-12-16","date_published":"2025-12-16","updated_at":"2026-07-22T22:18:44Z","subjects":["Alternative Interchange","Traffic Operations","Traffic Simulation","Critical Lane Volume Analysis","PTV VISSIM"],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:45307"],"render_values":[{"text":"vt_gsexam:45307","href":null,"code":true}]}]},"links":{"outbound_url":"https://hdl.handle.net/10919/139941","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Trani, Antonio A."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Katz, Bryan J.","Flintsch, Gerardo W."]},{"key":"dc:contributor.department","label":"Department","values":["Civil and Environmental Engineering"]},{"key":"dc:creator","label":"Author","values":["Dixit, Kushan Jatinbhai"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-12-17T09:01:32Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-12-17T09:01:32Z"]},{"key":"dc:date.issued","label":"Date","values":["2025-12-16"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Civil Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Alternative Interchange","Traffic Operations","Traffic Simulation","Critical Lane Volume Analysis","PTV VISSIM"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:45307"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/10919/139941"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This study evaluates the operational performance of a novel median U-turn interchange—St. Augustine U-turn interchange (SUTI)—as an alternative to a conventional median U-turn on arterial interchange (MUTAI) and four other existing service interchanges. The research integrates two analytical stages: Critical Lane Volume (CLV) analysis using the Highway Capacity Manual (7th Edition), and microsimulation analysis using PTV VISSIM with travel time and maximum queue lengths as the primary measures of effectiveness (MOEs). The simulation is conducted over ten random seeds per scenario to assess all the interchanges under various traffic demands, turning movement proportions, and traffic distributions. The results indicate that the new SUTI interchange required the lowest average cycle lengths to achieve the lowest volume-to-capacity (v/c) ratios, the second-best mean travel times, and the shortest mean maximum queue lengths across various demand scenarios. The conflict-point analysis revealed a reduction in conflict points when compared with conventional diamond interchanges. Overall, the SUTI and diverging diamond (DDI) interchange showed similar results. The new median U-turn design of the SUTI interchange demonstrates a significant improvement in travel time compared to the conventional MUTAI interchange."]},{"key":"dc:description.abstractgeneral","label":"General Abstract","values":["Traffic congestion and safety issues are growing concerns at highway interchanges, where vehicles from freeways and surface roads meet. Traditional diamond interchange designs can cause long delays, especially during peak travel hours. This study examines a new interchange design, known as the St. Augustine U-Turn Interchange (SUTI), which redefines how vehicles make left turns and enhances overall traffic flow. The SUTI interchange was compared to five other types of interchanges, including the conventional Median U-Turn on Arterial Interchange (MUTAI) and several popular urban interchanges currently in the United States. Using advanced computer simulation tools, the study tested how each interchange performed under different traffic conditions. The analysis focused on the duration of vehicle trips and the level of congestion at each location. The results showed that the SUTI interchange consistently achieved shorter signal times, lower travel times, and shorter queues than most of the other designs tested. It also showed fewer points where crashes are most likely to occur. The new SUTI interchange demonstrated operational performance comparable to that of the popular Diverging Diamond Interchange (DDI) and was superior to the conventional U-turn (MUTAI) interchange. Overall, the St. Augustine U-Turn interchange presents a promising operational solution for communities seeking safer and more efficient travel."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["ETD"]},{"key":"dc:title","label":"Title","values":["Evaluating the Operational Performance of St. Augustine U-turn Interchange (SUTI)"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Trani, Antonio A."],"dc:contributor.committeemember":["Katz, Bryan J.","Flintsch, Gerardo W."],"dc:contributor.department":["Civil and Environmental Engineering"],"dc:creator":["Dixit, Kushan Jatinbhai"],"dc:date.accessioned":["2025-12-17T09:01:32Z"],"dc:date.available":["2025-12-17T09:01:32Z"],"dc:date.issued":["2025-12-16"],"dc:description.abstract":["This study evaluates the operational performance of a novel median U-turn interchange—St. Augustine U-turn interchange (SUTI)—as an alternative to a conventional median U-turn on arterial interchange (MUTAI) and four other existing service interchanges. The research integrates two analytical stages: Critical Lane Volume (CLV) analysis using the Highway Capacity Manual (7th Edition), and microsimulation analysis using PTV VISSIM with travel time and maximum queue lengths as the primary measures of effectiveness (MOEs). The simulation is conducted over ten random seeds per scenario to assess all the interchanges under various traffic demands, turning movement proportions, and traffic distributions. The results indicate that the new SUTI interchange required the lowest average cycle lengths to achieve the lowest volume-to-capacity (v/c) ratios, the second-best mean travel times, and the shortest mean maximum queue lengths across various demand scenarios. The conflict-point analysis revealed a reduction in conflict points when compared with conventional diamond interchanges. Overall, the SUTI and diverging diamond (DDI) interchange showed similar results. The new median U-turn design of the SUTI interchange demonstrates a significant improvement in travel time compared to the conventional MUTAI interchange."],"dc:description.abstractgeneral":["Traffic congestion and safety issues are growing concerns at highway interchanges, where vehicles from freeways and surface roads meet. Traditional diamond interchange designs can cause long delays, especially during peak travel hours. This study examines a new interchange design, known as the St. Augustine U-Turn Interchange (SUTI), which redefines how vehicles make left turns and enhances overall traffic flow. The SUTI interchange was compared to five other types of interchanges, including the conventional Median U-Turn on Arterial Interchange (MUTAI) and several popular urban interchanges currently in the United States. Using advanced computer simulation tools, the study tested how each interchange performed under different traffic conditions. The analysis focused on the duration of vehicle trips and the level of congestion at each location. The results showed that the SUTI interchange consistently achieved shorter signal times, lower travel times, and shorter queues than most of the other designs tested. It also showed fewer points where crashes are most likely to occur. The new SUTI interchange demonstrated operational performance comparable to that of the popular Diverging Diamond Interchange (DDI) and was superior to the conventional U-turn (MUTAI) interchange. Overall, the St. Augustine U-Turn interchange presents a promising operational solution for communities seeking safer and more efficient travel."],"dc:description.degree":["Master of Science"],"dc:format.medium":["ETD"],"dc:identifier.other":["vt_gsexam:45307"],"dc:identifier.uri":["https://hdl.handle.net/10919/139941"],"dc:language.iso":["en"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Alternative Interchange","Traffic Operations","Traffic Simulation","Critical Lane Volume Analysis","PTV VISSIM"],"dc:title":["Evaluating the Operational Performance of St. Augustine U-turn Interchange (SUTI)"],"dc:type":["Thesis"],"thesis:degree_discipline":["Civil Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:18:44Z"}