Evaluating the Influence of a Freeway Capacity Improvement Project on Travel Time-Based Performance Measures Within Its Vicinity

Abstract

The focus of this research is on examining changes in travel time and related measures during the construction period and after increasing the capacity of a freeway corridor by comparing it with before the construction of the capacity improvement project in an urban area. Along with the freeway, the arterial streets connecting the freeway were also analyzed to assess changes within the vicinity of the project site. Further, the efficiency of the capacity improvement project in reducing congestion is evaluated by the time-of-the-day and day-of-the-week, during peak and off-peak periods on Wednesday, Friday, and Sunday. The findings indicate that travel times increased on the connecting arterial streets due to the migration of traffic from the freeway during the construction period. Also, at times, it appears that the travel time has decreased on the freeway due to the people choosing alternate routes rather than traveling through the construction zone. After the construction, there is a considerable amount of congestion even though the freeway travel time has decreased significantly. This could be due to the induced travel demand resulting in an increase in the travel time. The variations seem to marginally differ by the time-of-the-day and day-of-the-week. It is a general perception that an increase in capacity decreases travel times. However, a slight increase in travel time is observed on most of the links in the considered transportation network. Nonetheless, though there is an increase in buffer time, freeway expansion is very lucrative as a higher number of vehicles pass through a corridor with a marginal increase in travel time.