Developing a continuous flow intersection in Thailand | |
| Author | Jumrus Pitaksringkarn |
| Call Number | AIT Diss. no.TE-07-01 |
| Subject(s) | Traffic congestion--Thailand Traffic flow--Thailand Roads--Thailand Interchanges and intersections |
| Note | A dissertation submitted in partial fulfillment of the requirement for the degree of Doctoral of Engineering in Transportation Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. TE-07-01 |
| Abstract | As traffic congestion at major intersections has increasingly become one of the most prevalent and frustrating problems in many growing cities worldwide, recent advances in transportation technology and infrastructure development have introduced various remedies to relieve the problem, including the Continuous Flow Intersection design concept, or a CFI in short. This CFI design concept is an unconventional intersection that enhances the intersection capacity by using a special handling of right turns, considering left-hand side driving regions under study. Specifically, it allows right-turn traffic to cross an oncoming opposing traffic at approximately 100-120 meters before approaching the main intersection, in turn creating a two-phase signal controlled intersection at the additional crossing point. Though this CFI application may seem quite unconventional and unintuitive, a series of feasibility studies and analyses has been conducted while gaining more credibility and acceptance in the past few years as an advantageous alternative. However, a more extensive traffic study of the CFI should further be conducted. This research work proposes three study modules-I) an in-depth traffic operational performance analysis of the CFI to gain some insight to its operation performance, 2) a cost benefit analysis to evaluate and reconfirm its economical feasibility, and 3) a knowledge¬based decision support procedure for a CFI site selection-which must be undergone before an implementation of the CFI application in Thailand or other Asian countries could be made. The first module involves a careful evaluation of the traffic operational performance analysis through VISSIM micro-simulation modeling on a comprehensive set of intersection scenarios and demands. Specifically, the CFI's perfomiance is compared to that of the conventional intersection with both actuated and fixed time settings and both balanced and imbalanced traffic demands. The findings reveal that the CFI design concept could yield as high as 75 percent in travel time savings during peak hours. However, this work also discusses the limitation of CFI itself that can efficiently serve certain capacities of intersection-entering traffic demands. The second module focuses on the CFI's cost benefit analysis in monetary term, which includes travel time savings, vehicle operation cost savings, environmental cost savings, and traffic accident cost savings. In addition, the project cost of CFI implementation is determined for its benefit-cost ratio evaluation. The experimental results reveal that CFI is worth implementing at certain demands and scenarios, as the benefit cost ratios could range from 0.22 to 43.97. Taking the findings of both modules into consideration, the last element of this work develops a corresponding framework that serves in a knowledge-based decision support procedure for the CFI site selection. The four key factors-traffic volumellevel of service condition, physical feasibility and design consideration, traffic accident risk consideration and its safety treatments, and cost benefit ratio consideration-have demonstrated to be beneficial for a CFI implementation decision in Thailand. This work provides proper understanding of the underlying CFI design concept and reconfirms its prospect in conventional intersection improvements, when traffic conditions and constraints are appropriately taken into account. The proposed framework is expected to help establish an engineering method in providing a more systematic decision on how, when and where a CFI application should be implemented |
| Year | 2008 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. TE-07-01 |
| Type | Dissertation |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Transportation Engineering (TE) |
| Chairperson(s) | Pichai Taneerananon ;Hanaoka, Sinya (Co-Chairperson); |
| Examination Committee(s) | Kunnawee Kanitpong ;Hadikusumo, Bonaventura H.W. ;Sorawit Nurupiti; |
| Scholarship Donor(s) | Royal Thai Government Fellowship; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2007 |