The Impact of Commercial Parking Utilization on Cyclist Behavior in Urban Environments. (October 2020) - Jashami, Hisham
Highlights: Max CVLZ outperformed Min CVLZ and no CVLZ. In the no CVLZ scenario, 1/3 of cyclists used the sidewalk over the travel lane. Min CVLZ and the courier on the side negatively influenced cyclists' performance. Extra buffer for the courier improves bicyclist performance measures positively. Accessories behind the truck did not change the performance of cyclists. Abstract: With growing freight operations within the United States, there continues to be a push for urban streets to accommodate trucks during loading and unloading operations. Currently, many urban locations do not provide loading and unloading zones, which results in trucks parking in places that can obstruct roadway infrastructure designated to vulnerable road users (e.g., pedestrians and cyclists). In an effort to understand the implications of these truck operations, a bicycle simulation experiment was designed to evaluate the impact of commercial vehicle loading and unloading activities on safe and efficient bicycle operations in a shared urban roadway environment. A counter-balanced, factorial design was chosen to explore three independent variables: commercial vehicle loading zone (CVLZ) sizes with three levels (no CVLZ, Min CVLZ, and Max CVLZ), courier position with also three levels (No courier, behind the truck, beside the truck), and loading accessories (Acc) with two levels (no Acc, and with Acc). Cyclist's velocity and lateral position were used as performance measures. Data were obtained from 48 participants (24 women) resulting in 864 observations in 18 experimental scenarios. Linear Mixed-Effects Models (LMM) were developed to examine the effect of each independent variable level on bicyclist performance. Results from LMM model suggest that loading zone size had the greatest effect on cyclist's divergence. Additionally, when the courier was walking beside the truck, cyclist's velocity significantly dropped to almost one m/sec in compared when the courier located behind the truck. The presence of accessories had the lowest influence on both velocity and lateral positions of cyclists. In the no CVLZ scenarios, the delivery vehicle was parked at the bike lane, therefore; cyclists had to choose between using the travel lane or the sidewalk. About one-third of participants decided to use the sidewalk. These findings could support better roadway and CVLZ design guidelines, which will allow our urban street system to operate more efficiently, safely, and reliably for all users.