BAUER Foundations Canada Inc. was contracted in 2019 by Conwest Contracting to construct a temporary shoring wall for the Sophora At the Park pro-ject in Coquitlam, BC.
BAUER worked with the stakeholders involved to evaluate various options to optimize the initial secant pile wall design. The BAUER team ultimately select-ed a Cuter Soil Mixing (CSM) solution which yielded savings in duration, costs and helped mitigate risks traditionally associated with "wet piles" and the po-tential loss of interlock between adjacent piles. This value engineering exercise, paired with the early collaboration between BAUER and all other stake-holders, allowed for the development of the optimized design with minimal impact to the construction schedule.
BAUER utilized one BAUER BG30 CSM unit to install a total of 106 CSM overlapping panels, to provide temporary shoring and adequate water cut-off. The resulting wall was 20m in depth with an effective excavation depth ranging between 12.5m to 15.5m.
The soil conditions were up to 9m of compact sand and gravel underlain by a 2m thick compact sand layer, firm clay for another 2m and dense sand below that. The groundwater level was located at around 6.5m to 7.5m below grade.
Due to the presence of cobbles and occasional boulders, BAUER decided to replace the soil by means of pre-drilling with a BAUER BG28 rotary drill rig in order to remove any obstructions for the CSM unit. The pre-drilling operations also provided a homogenous matrix for the installation of the CSM panels, resulting in a higher quality final product.
Despite the unique challenges involved, the project was completed safely, within specifications and quality targets, to the satisfaction of the Client.