SienaStone - Colonial Creek

Wall System : SienaStone with Stratagrid 500 Geogrid Reinforcement
Owner: City of Waterloo, Waterloo, ON
Contractor: Gateman Milloy, Kitchener, ON
Designers: Layout: MTE Consultants Inc.
Structural Design: RisiStone Systems
Geotechnical Engineering: Naylor Engineering Associates
Wall Certification/Project Engineers: MTE Consultants Inc.
Manufacturer: Unilock Ltd., Glenn Wiley,Territory Manager

As part of an ongoing project to extend University Avenue, one of the main arteries in Waterloo, Ontario, the City recently completed construction of the Bridge at Colonial Creek. In response to environmental concerns, MTE Consultants designed the bridge to minimize the impact of the roadway on the existing creek.

The bridge deck and abutments are constructed of reinforced concrete and are abutted on all sides by SienaStone geogrid reinforced wing-walls. The four wing-walls run nearly parallel with the existing watercourse, perpendicular to the bridge.

Based on the location and proposed use, the design of the SienaStone geogrid reinforced walls had to comply with several additional criteria. Acting as bridge wing-walls, the analysis and design was conducted in accordance with the Ontario Highway Bridge Design Code, which currently calls for slightly higher margins of safety than the NCMA Design Manual. The presence of a creek in front of the wall required that special attention be paid to drainage at the wall face, scour protection, and depth of embedment. Finally, in an effort to minimise overall costs, the geogrid reinforcement design was optimised to allow reduced lengths as the walls tapered down to grade.

At the maximum height, the SienaStone wing-walls stand approximately 7.7m (25ft), then taper down rapidly (2.5H:1V) to near grade. For erosion protection, rip-rap is positioned in front and at the ends of the walls. The total face area of the walls is approximately 3500 square feet.

These walls highlight the capacity of the SienaStone system to combine rugged performance with an aesthetic quality rarely found in heavy highway and bridge applications. With aesthetics becoming an increasingly important issue in large commercial and government projects, the solid strength and lasting beauty of the SienaStone system will surely prove to be an attractive option to consultants and specifiers alike.