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Abstract:
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As transportation funding becomes increasingly constrained , it is imperative that
decision makers invest precious resources wisely and effectively . Transportation
planners need effective tools for anticipating outcomes (or ranges of outcomes ) in order
to select preferred project alternatives and evaluate funding options for competing
projects .
To this end , this thesis work describes multiple applications of a new Project
Evaluation Toolkit (PET ) for highway project assessment . The PET itself was developed
over a two -year period by the thesis author , in conjunction with Dr . Kara Kockelman , Dr .
Chi Xie , and some support by others , as described in Kockelman et al . (2010 ) and the
PET Users Guidebook (Fagnant et al . 2011 ) . Using just link -level traffic counts (and
other parameter values , if users wish to change defaults ) , PET quickly estimates how
transportation network changes impact traveler welfare (consisting of travel times and
operating costs ) , travel time reliability , crashes , and emissions . Summary measures (such
as net present values and benefit -cost ratios ) are developed over multi -year /long -term
horizons to quantify the relative merit of project scenarios .
This thesis emphasizes three key topics : a background and description of PET ,
case study evaluations using PET , and sensitivity analysis (under uncertain inputs ) using
PET . The first section includes a discussion of PET’s purpose , operation and theoretical
behavior , much of which is taken from Fagnant et al . (2010 ) . The second section offers
case studies on capacity expansion , road pricing , demand management , shoulder lane use ,
speed harmonization , incident management and work zone timing along key links in the
Austin , Texas network . The final section conducts extensive sensitivity testing of results
for two competing upgrade scenarios (one tolled , the other not ) ; the work examines how
input variations impact PET outputs over hundreds of model applications .
Taken together , these investigations highlight PET’s capabilities while identifying
potential shortcomings . Such findings allow transportation planners to better appreciate
the impacts that various projects can have on the traveling public , how project evaluation
may best be tackled , and how they may use PET to anticipate impacts of projects they
may be considering , before embarking on more detailed analyses and finalizing
investment decisions . |