There are a number of challenges that require careful planning, investigation and design when adopting existing heavily travelled arterial roads to accommodate Bus Rapid Transit (BRT) lanes. These include the widening/strengthening old deteriorated pavements, staging, grade raises, as well as Agency requirements related to extended service lives, timing rehabilitation to coincide with that on adjacent lanes, coloured pavements, to name a few. A section of Yonge Street in York Region that was originally built as a concrete pavement was subsequently realigned, overlain with asphalt and granular materials (the concrete was buried) and widened using flexible pavements. When designing the BRT lanes, one of the main challenges was to identify the locations where buried concrete could be encountered when excavating for the widening. Other challenges included variable pavement structures, and identifying the areas that require major strengthening/reconstruction to support the additional bus traffic. On Highway 7, also in York Region, the proposed BRT will use the existing median lanes with the road platform widened to accommodate new outside lanes. The challenge was to design a pavement structure for the widening that can have its service life significantly extended so as to minimize down time due to future maintenance activities. In addition, the rehabilitation work on the BRT lanes in the existing median and the outside lanes designed to have a long service life had to be synchronized. Red coloured or brick pavement was stipulated for the BRT lanes to differentiate them from the adjacent general traffic lanes. This paper summarizes the results of the field investigations which also included Ground Penetrating Radar (GPR) and Falling Weight Deflectometer (FWD) load deflection testing as well as the innovative pavement designs developed to address the design challenges.
