BAUER Foundations Canada Inc. was contracted by PCL Construction Management Inc. to install 14 foundation piles for the new 9th Ave S.E. bridge in Calgary, Alberta.
The new bridge replaces the original structure built in 1909, which connected the Ramsay and Inglewood communities to the City Centre and the rapidly developing East Victoria Park and East Village. In addition to having reached the end of its original lifespan, the aging bridge had a reduced load carrying capacity and did not meet current design and engineering standards.
Two large BAUER BG rotary drill rigs (BG 39 & BG 40) were mobilized on site for the piling operations. These rigs were capable of installing permanent casings in a single length without splicing, allowing the Client to accelerate the construction schedule. All piles were drilled using permanent casing of 1,320mm outer diameter drilled 2m into the underlying bedrock. The rock socket was formed with a diameter of 1,180mm.
The soil profile for the site consisted of 4m of Clay fill underlain by 6m of gravel and sandy silt. The sandstone bedrock was reached at an average of 10m below grade and had a strength of around 8 to 20 MPa.
Pile installation at this busy intersection in Calgary presented challenges in terms of maintaining a steady supply of concrete as well as coordinating the transportation and mobilization of casings/tools on site.
All the piles were tested using the Cross-hole Sonic Logging (CSL) methodol-ogy.
The project was completed safely, on schedule, within specifications and met all quality targets.