Ottawa is the Capital City of Canada and has established an efficient transit system over the past fifteen years. The Transitway is an exclusive bus corridor, with stations dotting the routes providing rapid transit service to the population of the Ottawa-Carleton region. Initial construction on the Transitway was completed using asphalt concrete as the paving material. Buses, including articulated models, travel in excess of 70 km/hr and brake from this high speed when stopping at the stations. This tremendous speed and braking force have caused severe rutting of the asphalt pavement under the wheel paths and in some cases have shoved the asphalt over the curb creating an unsafe condition. The bus station examined in this paper, "Campus Station", had been recently rehabilitated with a mill and overaly using Stone Mastic Asphalt (SMA). Within two years of the SMA rehabilitation, the rutting in the wheel paths was severe enough to require additional rehabilitation. Ultra-Thin Whitetopping (UTW) was chosen as a possible solution for rehabilitating severely rutted asphalt at Transitway Stations to restore safety and ride requirements. This paper will examine the design, construction and performance monitoring of the UTW pavement at Campus Station. Details include skid resistance, resistance to deterioration and scaling in cold climate and deicing salt conditions. The goal is to assess the suitability of UTW technology for use in bus station rehabilitation in Ottawa. (Author/publisher)
Abstract