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The dissertation develops analytical models that estimate the capacity of freeway weaving sections. The analytical models are developed using simulated data that were compiled using the INTEGRATION software. Consequently, the first step of the research effort is to validate the INTEGRATION lane-changing modeling procedures and the capacity estimates that are derived from the model against field observations. The INTEGRATION software is validated against field data gathered by the University of California at Berkeley by comparing the lateral and longitudinal distribution of simulated and field observed traffic volumes categorized by O-D pair on nine weaving sections in the Los Angeles area. The results demonstrate a high degree of consistency between simulated and field observed traffic volumes within the various weaving sections. Subsequently, the second validation effort compares the capacity estimates of the INTEGRATION software to field observations from four weaving sections operating at capacity on the Queen Elizabeth Way (QEW) in Toronto, Canada. Again, the results demonstrate that the capacity estimates of the INTEGRATION software are consistent with the field observations both in terms of absolute values and temporal variability across different days. The error was found to be in the range of 10% between simulated and field observed capacities. Prior to developing the analytical models, the dissertation presents a systematic analysis of the factors that impact the capacity of freeway weaving sections, which were found to include the length of the weaving section, the weaving ratio (a new parameter that is developed as part of this research effort), the percentage of heavy vehicles, and the speed limit differential between freeway and on- and off-ramps. The study demonstrates that the weaving ratio, which is currently defined as the ratio of the lowest weaving volume to the total weaving volume in the 2000 Highway Capacity Manual, has a significant impact on the capacity of weaving sections. The study also demonstrates that the weaving ratio is an asymmetric function and thus should reflect the source of the weaving volume. Consequently, a new definition for the weaving ratio is introduced that explicitly identifies the source of the weaving volume. In addition, the study demonstrates that the length of the weaving section has a larger impact on the capacity of weaving sections for short lengths and high traffic demands. Furthermore, the study demonstrates that there does not exist enough evidence to conclude that the speed limit differential between mainline freeway and on- and off-ramps has a significant impact on weaving section capacities. Finally, the study demonstrates that the HCM procedures model the heavy duty vehicle impacts reasonably well. This dissertation presents the development of new capacity models for freeway weaving sections. In these models, a new definition of the weaving ratio that explicitly accounts for the source of weaving volume is introduced. The proposed analytical models estimate the capacity of weaving sections to within 12% of the simulated data, while the HCM procedures exhibit errors in the range of 114%. Among the newly developed models, the Artificial Neural Network (ANN) models performs slightly better that the statistical models in terms of model prediction errors. However, the sensitivity analysis results demonstrate unrealistic behavior of the ANN models under certain conditions. Consequently, the use of a statistical model is recommended because it provides a high level of accuracy while providing accurate model responses to changes in model input parameters (good response to the gradient of the input parameters). / Ph. D.

The system dynamics methodology is used to develop a computer simulation model to determine whether to add lanes to a congested highway or build a new, more direct, facility. Fundamental to this evaluation is the incorporation of non-user measures of effectiveness to go with the traditional highway user measures of effectiveness, such as the Benefit-Cost Ratio. In the system dynamics methodology three alternative forms of the model of a system are used: verbal, visual, and mathematical. The verbal description is diagrammatic and shows cause-and-effect relationships between many variables in a simple, concise manner. The visual model or "causal diagram" is translated into a mathematical model and system equations. The model is comprised of four sectors: 1. population sector 2. economic sector 3. university sector 4. transportation sector The model applies to the area of Blacksburg, Christiansburg and Roanoke (city and county). with special treatment to Virginia Tech through the university model. The simulation results of the non-user benefits along with user benefits is used to evaluate the alternatives in the Blacksburg-Christiansburg-Roanoke corridor. / Ph. D.

The purpose of this study is to assist TxDOT engineers in the field of traffic control planning. This is to be done via the creation of a Geographic Information System (GIS) based tool. By bringing together information about TxDOT’s on-system roadways’ geographical locations, traffic demands, and capacities, one aggregate database has been established. Using the tools of GIS, Microsoft Excel, Microsoft Access, and VBA programming, a static clickable interface has been constructed. It enables users to access properties for any selected roadway link they desire. Expansion of the product to ArcIMS is ongoing to allow easy access for end users via the internet. / text

科学研究費補助金 研究種目:基盤研究(B) 課題番号:17360245 研究代表者:中村 英樹 研究期間:2005-2007年度

Submitted by José Dias (jmdiassor@gmail.com) on 2017-12-06T15:37:50Z No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) / Approved for entry into archive by Milena Rubi ( ri.bso@ufscar.br) on 2017-12-07T12:03:28Z (GMT) No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) / Approved for entry into archive by Milena Rubi ( ri.bso@ufscar.br) on 2017-12-07T12:03:40Z (GMT) No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) / Made available in DSpace on 2017-12-07T12:03:50Z (GMT). No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) Previous issue date: 2017-05-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / With the growth of urban population and the increase of the vehicle fleet, Brazilian cities face urban dysfunction problems like congestion, environmental pollution, car accidents among others and its consequences are felt by citizens. With the institution of the PNMU - Política Nacional de Mobilidade Urbana (National Urban Mobility Policy), Brazil has sought to direct the planning of solutions for the urban transportation of people and cargo in an integrated and sustainable way The literature shows a lack of national research focused on planning and local policies of urban freight and better understanding of the authorities on the freight transportation and supply chains, for decision-making on policy and planning Urban Freight Transport (UFT). The practices and concepts of City Logistics intend optimal solutions for goods handling issues in urban areas. In this context, the use of City Logistics (CL) practices in Brazilian cities was investigated. Therefore, the contents related to UFT and CL were analyzed in the PlanMobs – Planos de Mobilidade Urbana (Urban Mobility Plans) elaborated by these cities. Additionally was produced a data collection (survey research), with those responsible for the preparation/review of PlanMobs. This research identifies the resources used in the UFT planning, the CL practices adopted and the perceptions of the municipal authorities about the UFT and CL. The results showed that the LU is still neglected and appears not to be the focus of the authorities who have developed the PlanMob. The lack of local authorities’ specific skills, with the low use of planning resources makes it impossible to achieve the LU goals. / Com o crescimento da população urbana e o aumento da frota de veículos, as cidades brasileiras enfrentam problemas de disfunções urbanas como congestionamento, poluição ambiental, acidentes, cujas consequências são vivenciadas pelos cidadãos. Com a instituição da Politica Nacional de Mobilidade Urbana (PNMU), o Brasil procurou direcionar o planejamento de soluções para o transporte urbano de pessoas e cargas de forma integrada e sustentável. A literatura mostra a falta de pesquisas nacionais com foco no planejamento e políticas locais de frete urbano e de melhor entendimento das autoridades sobre o transporte de cargas e das cadeias de suprimentos, para a tomada de decisão sobre políticas e planejamento do Transporte Urbano de Cargas (TUC). As práticas e conceitos da Logística Urbana buscam soluções para a problemática da movimentação urbana de mercadorias. Neste contexto, investigou-se a utilização das práticas da Logística Urbana (LU) nas cidades brasileiras. Para tanto, foram analisados os conteúdos relativos ao TUC e LU nos Planos de Mobilidade Urbana (PlanMob) elaborados por estas cidades. Adicionalmente elaborou-se um levantamento de dados (pesquisa tipo survey), junto aos responsáveis pela elaboração/revisão dos PlanMobs. Esta pesquisa identifica os recursos utilizados no planejamento do TUC, as práticas de LU adotadas e as percepções das autoridades municipais sobre o TUC e a LU. Os resultados demostraram que a LU ainda é negligenciada e parece não ser o foco das autoridades que têm elaborado o PlanMob. A falta de competências específicas das autoridades locais, com a baixa utilização dos recursos para o planejamento impossibilita o alcance das metas da LU.

The 2+1-road is a specific three lane road which aims to increase the safety of the predecessor 13 meter wide four lane roads. As a lane is removed and a weaving section is introduced the capacity is severely lowered, sometimes halved. A very demanding part of the traffic system with regards to capacity are heavy vehicles, especially in conjunction with the 2+1-roads. However, exactly how the share of heavy vehicles impacts the traffic system with regards to 2+1 roads and freeways is not previously studied, which grants the opportunity of this work. The work has been carried out in connection with an assignment from The Swedish Transport Administration of analyzing the E4 going north from Gävle. This study analyzes how the share of heavy vehicles and level of service affect the speed on the two types of roads. The Swedish Transport Administration currently bases their current relationships on speed, capacity, and level of service on a share of heavy vehicles of 12%, which may give slightly wrong results depending on which system is being analyzed. The study has been carried out through micro simulation, which is a method that is very dependent on what data it is given, such as behavioral parameters and other input. The results of the study show how the relationship between share of heavy vehicles and level of service affect the speed, and that the 2+1-roads are highly dependent on the share of heavy vehicles, whereas the freeways have much larger tolerances. / Den mötesfria vägen (s.k. 2+1-väg) tillkom på 90-talet och gav upphov till mycket mer trafiksäkra vägar än sina föregångare 13-metersvägarna från mitten av 1900-talet. Till följd av säkerhetsökningen kom uppoffringar i kapacitet i och med vävningssträckor, som mer än halverar kapaciteten i jämförelse med en tvåfilig väg. En mycket kapacitetskrävande del av trafiksystemet är lastbilar, framförallt i dessa vävningssträckor. Men exakt hur lastbilsandelar påverkar systemet är inte riktigt bearbetat än, vilket ger upphov till detta examensarbete. Studien har utförts i samband med ett uppdrag från Trafikverket angående simulering av E4:an norr om Gävle. Detta examensarbete granskar alltså hur lastbilsandelen och belastningsgraden påverkar punkthastigheten på de två vägtyperna mötesfri väg och motorväg. Trafikverket baserar sina effektsamband på en lastbilsandel på 12 %, vilket kan ge både för låga och för höga värden beroende på vilken plats som man granskar. Arbetet har genomförts med hjälp av mikrosimuleringsmodeller, vilka är mycket beroende av vilka parametrar och indata de får. Resultatet av studien visar hur punkthastigheten beror på lastbilsandel och belastningsgrad, och visar på att de mötesfria vägarna är mycket beroende av lastbilsandelen, medan motorvägar har betydligt större tolerans.