Client / FTG Constructors
Construction Cost / $70 Million

Project Description
The steep terrain on the South Fraser Perimeter Road required the largest quantity of MSE walls on a highway project in British Columbia – over 63,000 m2. Different proprietary systems were procured depending on the geography:

  • 26,000 m2 of rock-faced galvanized steel straps from SSL
  • 24,000 m2 of rock-faced geogrid straps from Nilex
  • 8,000 m2 of 70 degree green MSE walls from Nilex
  • 5,200 m2 of two-staged abutment precast panel MSE walls from Nilex

Typically, select granular quarried aggregate is used as backfill however the project team received over $1 million in savings by using Fraser River sand. The team performed triaxial tests to confirm the sand friction angle. The sand caused a slight increase in the MSE strap length and thus caused greater excavation however; the sand was much more cost effective and allowed for all-weather construction due to its porous nature.

Other cost savings were employed on the MSE walls including:

  • Using extensible geogrid in bridge abutments where it is typically not allowed
  • Founding true bridge abutments directly on MSE walls as tall as 18 meters
  • Designing split grade(tiered) MSE walls to reduce excavation volumes

RAM Engineering Role
RAM was retained by the joint venture FTG Constructors to manage the MSE wall design, procurement, tendering and construction. A variety of subcontractors and self-perform crews were managed to build the different systems