Comprehensive method for evaluating signalized intersections treatments: Left turn prohibition and partial grade separation.

详细信息   

• 作者：Yu ; Xin.
• 学历：Ph.D.
• 年：2013
• 导师：Prevedouros, Panos D.,eadvisorLi, Honglongecommittee memberTeng, Michelle H.ecommittee memberFlachsbart, Peter G.ecommittee memberBabcock, Roger W.ecommittee member
• 毕业院校：University of Hawaii
• Department：Civil and Environmental Engineering
• ISBN：9781303314124
• CBH：3572501
• Country：USA
• 语种：English
• FileSize：7052263
• Pages：346

文摘

Recurring congestion at signalized intersections is caused by the inability of traffic signal controls to serve demand even in cities where advanced traffic signal timing and management systems are in operation. Left turn prohibition LTP) and partial grade separation with low-clearance underpass LCUP) are possible congestion mitigation actions for urban complex and congested signalized intersections that have exhausted other options for capacity enhancement such as lane addition and signal timing optimization. LTP and LCUP improve traffic signal efficiency by eliminating signal phases, increasing green splits or adding lanes. They also improve intersection safety by eliminating certain conflicts. At the same time, they necessitate traffic rerouting, may have negative impacts at downstream locations, and may have perceived or actual impacts to accessibility and neighborhood character. A comprehensive method considering multiple objectives, stakeholders, and attributes of a proposed treatment is inherently complicated. There is currently unavailability of methods pertaining to address the lack of techniques to integrate operation, safety, economic, stakeholder objective analysis and uncertainty into multi-attribute decision-making tool. A complete set of stakeholders is also absent, including motorists, pedestrians, bicyclists, adjacent businesses and residents and responsible agencies. This research proposes a three-level project decision-making process taking into account the planning and screening, feasibility and performance study, and evaluation and decision-making in the development of an intersection improvement project. A planning and screening level is to quantify and compare the benefits and costs LTP and LCUP was developed to examine the potential applicability of these congestion mitigation actions by examining intersection delay using the Highway Capacity Manual 2010, accident frequency using the Highway Safety Manual, and cost-benefit analysis based on AASHTO&rsquo；s User Benefit Analysis for Highways Manual, prior to conducting extended data collection and detailed analysis. Feasibility and performance analysis is to examine the feasibility of a treatment by considering site-specific constraints, and if feasible, conduct detailed performance analysis using advanced analysis tools. Five-stage multiple attribute evaluation under uncertainty and fuzziness MAFU) process is proposed in evaluation and decision-making level, which is able to assess the magnitudes of intersection treatment performance and to the fuzziness in stakeholder preference and the uncertainty in performance measurement. MAFU is designed to determinate the alternative which can best achieve a compromise between all competing objectives and conflicting interests. It features fuzzy mathematics FAHP) to capture the stakeholder preferences, utility function theory MAUT) to combine performance measures and describe risk sensitivity, and probabilistic approach MCS) to model output uncertainties and conduct the tradeoff analysis. A case study is provided to demonstrate the application of this integrated and comprehensive method and the reliability of using this method for project evaluation and decision-making. Due to the complexity of analysis for various time periods and multiple locations, a spreadsheet-based tool was developed for the planning and screening level and the evaluation and decision-making level. The study presents and demonstrates the comprehensive evaluation and decision-making process using the left-turn prohibition and low-clearance underpass treatments, but the method itself is generic and can be further extended to other intersection treatments and transportation projects.