Impact of Operational Speed Characteristics of Heavy Vehicles on High-Speed Highways

This thesis explores the safety impact of differential speed limit (DSL) strategy by considering gross vehicle weight (GVW) combined with average speed enforcement (ASE) for heavy vehicles. The study used one-year of Weigh-in-Motion (WIM) data (2014) and one-month of Global Positioning System (GPS) data (Mar 2016) collected from along the Trans-Canada Highway 1 in British Columbia. The research consisted of a data-driven analysis and a two-part simulation analysis. As the DSL investigated was based on GVW, a Modified-Federal Highway Administration (M-FHWA) classification that explicitly considered GVW was tested alongside the FHWA classification regarding average speed and GVW. The simulation analysis assessed the DSL strategy associated with M-FHWA classification and ASE strategys impact on the safety of heavy vehicles. In general, the analyses showed that DSL adopted with M-FHWA classes combined with ASE would be effective in reducing heavy vehicle speed and improving highway safety.