Houle Chevrier Engineering was retained by Novatech Engineering Consultants Ltd., on behalf of the City of Ottawa, to provide geotechnical services for the detailed design, permitting, and construction review of the bridge and approach embankments for a three-span, 27 m long bridge crossing of the Carp River in Ottawa. The project site is located within the Carp River valley, an area underlain by up to 6 m of peat and 25 m thick deposits of soft silty clay of marine origin.
The final bridge design and construction were commissioned as part of the Government of Canada Economic Action Plan in 2009. Houle Chevrier Engineering Ltd. used available borehole information and, together with our extensive local experience, provided a design for the approach embankments so that they could be completed at low-risk within the funding deadline, while maintaining settlements within acceptable limits. Various options were considered, including wick drains, light weight slag fill, and light weight expanded polystyrene (EPS). An EPS fill embankment was implemented after a thorough review of the costs, settlement, and time related risks of each option.
Project components included:
- 3D stress and settlement analysis
- Technical review of the piling installation and testing
- Settlement, inclinometer and piezometer instrumentation design and monitoring
- Design advice for a 900 mm watermain below the river and adjacent to the embankment
- Peat removal and replacement; and river diversion recommendations