UBC Theses and Dissertations
UBC Theses and Dissertations
Urban goods movement : providing priority for trucks along a major arterial Clement, Henry Sebastian
The economy of a major urban area is dependent on a transportation system that permits the efficient movement of people and goods. Urban goods movement is a complex and multi-faceted task that is often overlooked in transportation planning. Commercial vehicle operators are faced with mounting levels of congestion delay as they compete for limited road space with ever-growing commuter traffic. No major urban area today is immune to the problems linked with growing traffic congestion and its negative impacts to economic competitiveness and industrial productivity. The Knight Street corridor in the City of Vancouver is a major truck route that serves the Port of Vancouver and various industrial areas to the north. Towards the south, this corridor connects to the Lower Mainland's highway system providing trucks access to the United States and the rest of Canada. The Knight Street corridor is designated as a truck route and consequently carries a high percentage of heavy vehicles. A transportation microsimulation model, Paramics, was used to evaluate various strategies to benefit truck movements along the Knight Street corridor. Paramics includes a suite of tools for modelling the interaction and dynamic effects of vehicle movements. A significant amount of time was dedicated to the calibration and validation of the model to actual turning movements and travel times. Travel time was used to ensure the accuracy of the model using global positioning system (GPS) technology. Because of high vehicle volumes and a large proportion of truck activity and consequent congestion problems, several strategies to enhance the movement of trucks along the Knight Street corridor were modelled using the microsimulation model. Signal coordination improvement strategies were investigated to facilitate the movement of trucks along Knight Street as well as the impacts of an exclusive truck/bus lane. Transyt-7F was used to calculate the signal offsets for two-way coordination along the corridor. Signal offsets were adjusted for varying proportions of heavy vehicles which is not typically accounted for in traditional signal coordination studies. A scenario was also set up with variable signal coordination offsets to further enhance the efficiency of the normal signal coordination plan. The impact of additional left turn capacity was also modelled for travel time benefits. The modelling results of an exclusive truck and bus only lane shows the travel time benefits to heavy vehicles. Trucks see a 14% and 9% reduction in travel times northbound and southbound along the entire corridor respectively. Since one lane of capacity is removed for automobiles, they see a 7% and 5% increase in travel time in the northbound and southbound directions respectively. Using Transyt-7F to develop a two-way signal coordination plan for Knight Street resulted in an average 13% savings in travel time along the corridor. There was also a significant reduction in travel time variability which is an important consideration for truck operators. Having a higher proportion of trucks reduces travel time along the corridor as heavy vehicles reduce the average platoon speed. Having 20% and 25% trucks along the corridor reduced travel time by 3% and 5% respectively over the base case of 15% trucks. The platoon speeds were reduced in Transyt-7F to reflect the slower travel speed with more trucks to develop two-way signal coordination strategies for higher proportions of heavy vehicles. Travel times along the corridor were reduced by approximately 12% with higher proportions of heavy vehicles with signal coordination. As travel times vary significantly throughout the two hour peak period, variable signal offsets were tested for travel benefits over the fixed offset scenario. Signal offsets were adjusted to reflect the changing travel times with a marginal decrease in travel times over the fixed offset strategy. A Combination of signal coordination with an exclusive truck/bus lane was modelled for travel time benefits as well. Northbound auto and truck travel times were reduced by 8% and 21% respectively, while southbound auto and truck travel times increased by 20% and 3% respectively. Higher intersection approach volumes are the cause of the increase in southbound travel time as 14% more vehicles are attracted to the corridor. Increasing left turn bay capacity at four key intersections was modelled with a resulting 3% reduction in travel times in both directions. Adding this capacity also resulted in 15% more approach volumes at the four improved intersections. Delay at the northbound approach to 49th Ave and 57th Ave were reduced significantly as through movement vehicles were no longer blocked by left turning vehicles.
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