Groat Road Bridges and Road Renewal
Location: Edmonton, AB
In January 2018, Graham was selected as the General Contractor to complete the Groat Road Bridges and Road Renewal project in partnership with the City of Edmonton and the City’s Design Consultant. This project involved the rehabilitation of three bridges and approximately 5km of surrounding roadway. The three bridges on the project included the Groat Road Bridge over Victoria Park Road and Emily Murphy Park Bridge over Groat Road, both single-season bridge rehabilitations, and the Groat Road Bridge over the North Saskatchewan River (the River Bridge), which underwent a full superstructure replacement and substructure rehabilitation.
Originally constructed in the 1950s, the River Bridge is a seven-span, four-lane structure that carries traffic and pedestrians 1,000 feet across the North Saskatchewan River Valley and provides a critical transportation link between downtown Edmonton and the University area. Approaching the end of its service life, it was determined that the bridge should undergo a substantial structural rehabilitation to allow it to continue to serve Edmonton commuters for decades to come. The demolition and reconstruction of the bridge superstructure was phased to ensure continuity of two-way vehicular and pedestrian traffic throughout construction. Graham ultimately selected the innovative use of twin gantry cranes to demolish and rebuild the River Bridge. The demolition program for the River Bridge involved a highly engineered sequence of reinforcement, sawcutting, and hoisting of each individual deck and girder segment in up to 80-ton pieces. Following removal of the superstructure, select components of the existing piers and abutments were removed. Once demolition was complete, Graham constructed the new cast-in-place substructure elements, installed multiple bearing types, and erected haunched steel plate girders. The cast-in-place bridge deck was constructed through an innovative construction sequence that overlapped girder erection, deck falsework, formwork, and reinforcing steel, and reduced the duration of the reconstruction program by several months. Once the deck and barriers were cast, hot-applied waterproofing was placed, and an asphalt wearing surface and HPC shared use pedestrian path were constructed. This cycle was repeated for both Phases of the River Bridge program. The final bridge configuration involved the restoration of two lanes of traffic in each direction, coupled with an expanded pedestrian and cyclist shared-use-path.
Another key scope of work on the River Bridge was the modifications to the existing concrete bridge piers. The faces of the piers above the waterline required partial depth repairs and crack injection to restore their function, and the base of three of the piers required a new concrete collar to effectively change the mechanics of the bridge. Each of these scopes required that Graham establish in-stream access; this work required considerable pre-planning, as Graham’s ability to do work within the North Saskatchewan River was governed by in-stream access periods along with the requirements of several different regulators. Graham ultimately completed these scopes using three access methodologies. The pier face work was completed using manlifts on a winter ice road. The pier base collars were constructed using small finger berms and barges for access, coupled with sheet-piles for isolation. For all three methods of access, Graham managed the purpose-driven temporary works design development, coordinated those plans with the application for and receipt of environmental permits, and executed the work. Graham managed the permitting process with several regulatory bodies, including the Department of Fisheries and Oceans, Transport Canada, the Public Lands Act and the Waters Act. Once the river bridge superstructure construction and in-stream work were complete, Graham constructed the supporting recreational features in Emily Murphy Park. The scope of work included clearing and grubbing, excavation, installation of a concrete anchor block and Owner supplied floating dock, backfill and rip rap, gravel trails, concrete curbs and plaza, timber steps, site furniture and landscaping. As a portion of this work was in-stream, this work also included environmental management in accordance with the regulatory permits. Prior to the construction program, within the project limits, Groat Road served approximately 40,000 daily commuters linking the downtown and University areas in Edmonton. A key component of work on the Groat Road Bridges and Road Renewal was the development and implementation of traffic and pedestrian management plans throughout construction. Minimizing the impact to the public was always a key consideration throughout construction. Early planning and excellent communication with The City allowed all traffic pattern changes and impacts to be communicated proactively to the public through social media and on the project website. Graham also installed signage to inform the pedestrians and cyclists of any closures to the trail system, sidewalks, and shared use paths. Graham was required to develop detailed staging plans that coordinated work on the roads and bridges with the City’s traffic team, and then execute the work in accordance with the traffic and staging plans.
City of Edmonton