Date of Award
Doctor of Philosophy (PhD)
Civil and Environmental Engineering
Adaptive Traffic Control System, Benefit / Cost Analysis, Life Cycle Assessment, Life Cycle Cost Analysis, Ramp Metering System
The primary objective of Transportation Systems Management and Operation (TSM&O) strategies, or Intelligent Transportation Systems (ITS) is to optimize the capacity of existing transportation infrastructure by reducing congestion. Over past decades, agencies and researchers investigated the use of various strategies such as deployment of adaptive traffic control systems (ATCS), ramp metering systems (RMS), surveillance through closed circuit TV (CCTV) cameras, and information sharing systems to achieve this objective. Life Cycle Agency Cost Agency Analysis (LCCA) of various alternative intelligent transportation strategies has received particular attention to identify the strategy with the lowest cost. However, increasing concerns over the impacts of transportation systems on nearby communities as well as the environment are urging decision makers to consider the environmental impacts of various TSM&O strategies in addition to user costs.
Sustainability refers to a long-term perspective of economic, social and environmental progress, which not only addresses the present conditions but also includes the needs of future generations. In United States, due to its vastness, transportation infrastructure can be considered as “major contributors of sustainability”. The triple bottom line of sustainability (TBL), if incorporated in TSM&O strategies decision-making, can address issues like climate change, environmental protection, funds optimization, and social equity.
The work for this dissertation focuses on developing a comprehensive Life Cycle Benefit/Cost (LCB/C) analysis framework to evaluate existing and anticipated intelligent ITS strategies, particularly, adaptive traffic control systems (ATCS) and ramp metering systems (RMS), in terms of the triple bottom line (TBL) of sustainability. The B/C framework for each ITS category was divided into two main categories: Life Cycle Cost Analysis (LCCA) and Life Cycle Benefit Analysis (LCBA). The LCCA of ITS deployment includes initial infrastructure cost, periodical incremental cost, and O&M cost. A typical service life and interest rate are assumed for each ITS. For the benefits analysis, three main research areas are included. Conducted by the triple bottom line principal, the LCBA section is divided into analysis of benefits through travel time savings, reductions in energy consumption, and safety enhancements.
ITS are known to have several advantages such as increasing link capacity, accelerating traffic flow, reducing delay and congestion, decreasing safety concerns, and in turn minimizing environmental and socio-economic impacts associated with affected traffic zones. However, it comes with its own share of disadvantages, like higher initial infrastructure cost and periodical incremental cost, design complexity, and challenges lie in operation and maintenance. Meanwhile, it is hard to evaluate the benefit/cost performance of ITS implementation over the service life span. The purpose of this study is to prepare such comprehensive benefit/cost framework, as well as the corresponding decision support tool featuring data obtained from national averages. The tool is spreadsheet based and it is easily customizable. The tool also generates graphical outputs as visual summaries. The framework and tool, will help decision makers to assess the overall performance of ITS from perspectives of long term costs and triple bottom line benefits, then opt for the most suitable alternatives from the life cycle point of view.
Chen, Xifan, "A LIFE-CYCLE BENEFIT/COST ANALYSIS FRAMEWORK FOR ITS DEPLOYMENTS" (2017). Dissertations - ALL. 826.