MSE Wall/Box Culvert Embankment Reinforcement

This project  involved construction of a temporary earthen retaining structure, known as mechanically stabilized earth wall (MSE wall) for an approach embankment as a part of a box culvert installation.

Location was the biggest challenge with this project. Being alongside Trans-Canada Highway meant that working space needed to be confined to ensure safe traffic flow without affecting the construction schedule.

The conventional solution to this would involve a cofferdam however, cofferdams are constructed with sheet piling designed to be more of a permanent solution rather than a temporary one. In addition, sheet piling is a solution that is more suited to a larger footprint area and wouldn't work in the confines of this construction site. Being along a road is also far too dangerous therefore unfeasible for this site.

Titan Solution

Responding to both confined working space and safety considerations, Titan proposed a temporary MSE Wall solution using our Pyramid Grid™ designed for soil slope reinforcement.

The MSE wall was designed for two heights, 5.7m near the box culvert and 3.0m away from the box culvert. Each layer of geogrid was wrapped back into the fill (3/4" down) with a minimum anchorage length of 1000mm, and the vertical spacing between the layers was 500mm.

The wall was designed in accordance with AASHTO LRFD method using MSFW (3.0) software to calculate internal and external stability. And global stability was checking using ReSSA (3.0).

Not only was this is a safe solution but it provided approximately 40% in material and time savings to both the client and the contractor.

Pyramid Grid™ is a high-strength uniaxial polyester geogrid engineered for soil reinforcement, offering exceptional tensile capacity, durability, and stability in demanding construction environments.

Achievement

Titan successfully delivered an innovative and cost-effective solution by implementing their Pyramid Grid™ system to construct a temporary MSE wall for a box culvert embankment. This approach not only addressed the spatial and safety constraints of working adjacent to the Trans-Canada Highway but also resulted in approximately 40% savings in both material and construction time. The design ensured structural stability, minimized traffic disruption, and eliminated the need for more invasive and permanent methods like sheet piling, showcasing the effectiveness and adaptability of the Pyramid Grid™ system.