With growing freight operations worldwide, there is a push for transportation systems 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 obstruct bicyclist’s roadway infrastructure (e.g., bicycle lanes).
A bicycle simulation experiment was designed in the USA to evaluate the impact of commercial vehicle loading and unloading activities on safe and efficient bicycle operations in a shared urban roadway environment to understand the implications of these truck operations.
A fully counterbalanced, partially randomized, factorial design was chosen to explore three independent variables: commercial vehicle loading zone (CVLZ) sizes with three levels (i.e., no CVLZ, Min CVLZ, and Max CVLZ), courier position with three levels (i.e., no courier, behind the truck, beside the truck), and with and without loading accessories. Bicyclists’ physiological responses and eye tracking were used as performance measures. Data were obtained from 48 participants, resulting in 864 observations in 18 experimental scenarios using linear mixed-effects models (LMM).
Results from the LMMs suggest that loading zone size and courier position had the greatest effect on bicyclists’ physiological responses. Bicyclists had approximately two peaks per minute higher when riding in the condition that included no CVLZ and courier on the side compared to the base conditions (i.e., Max CVLZ and no courier). Additionally, when the courier was beside the truck, the bicyclist’s eye fixation durations (sec) were one (s) greater than when the courier was behind the truck, indicating that bicyclists were more alert as they passed by the courier. The presence of accessories had the lowest influence on both bicyclists’ physiological response and eye-tracking measures.
These findings could support better roadway and CVLZ design guidelines, allowing our urban street system to operate more efficiently, safely, and reliably for all users. Individuals were then asked in which scenario they felt most comfortable. Forty-five participants (90%) indicated “The commercial vehicle far from the bike lane (wider loading zone)” they felt the most comfortable with, followed by four participants (8%) indicating “The commercial vehicle adjacent to the bike lane (narrow loading zone)” and one participant (2%) indicating “The commercial vehicle in the bike lane (no loading zone)”.