Final contract report benefits estimates of highway capital improvements with uncertain parameters
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 is the travel time in hours under peak volume-to-capacity ratio and is estimated by a traditional BPR (the United States Bureau of Public Roads) curve and related BPR equation adopted from a current VDOT methodology:
where
 is the free flow travel time (hours)
The free flow travel times, is given by:
where
 is the roadway length influenced by the project
 is the free flow speed.
The free flow speeds for different road types are adopted from NCHRP-B (1999) and are provided in Table 4. It is assumed that the implementation of a candidate project results in a reduced volume to capacity ratio at project location. A global uniform range for reduced volume to capacity ratio is fixed for all the projects. Annual peak hours before capacity enhancement are estimated for each project using the above equations and the current volume to capacity ratio. Similarly, lower and higher values of the annual peak hours after a capacity enhancement are estimated for each project using the lower and higher values of reduced volume to capacity ratio respectively. The difference between the before implementation and after implementation values is the annual benefit in travel time savings during peak hours attributable to the implementation of the project. The benefit is divided by an equivalent annual project cost to obtain a cost effectiveness measure as travel time saved per dollar invested. 
where
 is the annual peak vehicle hours prior to capacity enhancement
 is the annual peak vehicle hours after capacity enhancement
For each project, low, high and median estimates of the cost-effectiveness measure are calculated using above formulation. Directory: crmes crmes -> Standard Specifications For Structural Supports for Highway Signs crmes -> Virginia Department of Aviation System Inventory crmes -> Process Control for Risk Identification and Anomaly Detection crmes -> Virginia Department of Transportation System Inventory crmes -> VTrans2025 Multimodal Investment Network (min) Statement Route 64 Corridor I. Introduction crmes -> Multimodal Impact Network (min) Statement TransAmerica us 460 Corridor I. Introduction crmes -> Future Scenarios for Multimodal Transportation Planning Prepared for Download 1.14 Mb. Share with your friends:
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