Freight deliveries on signalized urban streets are known to cause lane blockages during delivery. Traffic congestion associated with urban freight deliveries has gained increasing attention recently as traffic engineers and planners are tasked with finding solutions to manage increasing demand more sustainably with limited road capacity. The goal of this research is to evaluate two models for quantifying the capacity and signalized control delay effects of a lane-blocking freight delivery on an urban arterial. The two methods are: an All-or-Nothing model similar to methodology used in the Highway Capacity Manual 6th Edition, and a Detailed model consistent with kinematic wave theory. The purpose is to provide insight on the use of these tools for analysis of urban freight delivery. The signalized control delay results of the two models are compared with observed video data of urban deliveries from one city block of 8th Ave in New York City. Empirical confirmation of double-parked delivery impact on signalized controlled delay remains elusive due to an inability to isolate the effects of the deliveries from other traffic perturbations in the video sample. Instead, microscopic simulation using Aimsun is used for comparison to the theoretical models and the results lend credibility to the Detailed model. The simulation results show a similar trend of delay impact from double-parked deliveries located at a range distances from the intersection and more closely resembled the Detailed model. The All-or-Nothing model would provide only a coarse representation of the capacity and delay effects. The more detailed approach that accounts for the dynamics of queuing in front of the delivery vehicle provides closed form analytical formulas for capacity and signalized control delay that can account for varying locations of deliveries as well as analysis periods with some blocked cycles and others unblocked. Two policy implications are proposed: 1) that double-parked deliveries located mid-block likely result in less signalized control delay impact, and 2) freight receivers that attract double-parked deliveries near an intersection stop line should be prioritized in urban freight delivery mitigation policies such as off-hour delivery.
| Identifer | oai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:masters_theses_2-1762 |
| Date | 25 October 2018 |
| Creators | Keegan, Aaron J. |
| Publisher | ScholarWorks@UMass Amherst |
| Source Sets | University of Massachusetts, Amherst |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Masters Theses |
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