Soil Stabilization
Tough Cell® geocells are an effective solution for soil stabilization applications such as slopes and embankments. These flexible, honeycomb-like cells are installed on the ground and then filled with soil to provide structural support and prevent erosion. The cells form a strong, flexible matrix that can withstand heavy loads and prevent movement of the soil.
One advantage of using a Neoloy® based geocell like Tough Cell® over an HDPE based geocell is that the Neoloy® material is stronger and more stable in extreme conditions, providing better performance in challenging soil conditions. This allows for a wider range of applications and more effective soil stabilization.
In slope and embankment applications, Tough Cell® can be used to reinforce the soil and prevent it from sliding or collapsing. The cells provide a stable foundation for vegetation to grow, helping to further stabilize the slope and prevent erosion.
Solutions
- TOUGH CELL® – cellular confinement system or geocell for soil stabilization and reinforcement
- STRATUM LOGICS – engineering partner focused on creating custom solutions
Resources
Project Profile
Grierson Hill Slope Stabilization
In a bid to provide improved public transit in the Edmonton Metropolitan area, the city has been engaged in an ambitious project to build a light rail system. The project has been underway since 1978, and one of the newest editions to the transit system was to be built next to a steeply graded slope. Grierson Hill was a notorious hill in the Edmonton region. It measured in at a whopping 666m/2 185ft a.s.l. This was a mammoth project, and the right team was needed to defeat it. The Grierson Hill slope above the LRT track was made up of two portions – the first portion was the slope, composed of a soil/clay mixture that was stabilized utilizing soil nails. The second portion consisted of 100% embankment with no supporting materials other than the natural slope.
Because the slope is at such an angle, it would be a complex task to stabilize the terrain while simultaneously maintaining the native vegetation. This made it quite difficult for workers to stabilize the slope so construction could continue. Paradox Access Solutions needed to stabilize the slope with ToughCell™, which keeps everything in place long enough for vegetation to take root allowing the dirt to become stable through vegetation.
The Challenge
It was a challenge to get vegetation to grow on that slope, especially when it was a steep one. The bank needed to be stable, or the vegetation wouldn’t hold it together.
Grierson Hill has always been a sore spot in Edmonton because it always wants to slough down towards the river. They still needed structures on top of the bank though, so most of their solutions involved soil nailing. Soil nailing is a ground stabilisation technique that can be used on either natural or excavated slopes. It consists of drilling holes for steel bars to be inserted into a slope face, which are then grouted in place. Mesh is then attached to the bar ends to hold the slope face in position. Usually, this is an adequate solution, but in the case of Grierson Hill, it wouldn’t be enough.
The Solution
The key to making our bank sustainable was building a surface that supported native vegetation.
The problem is, we couldn’t just leave this steep slope as-is—it’s too unstable for us to use for anything. We needed to stabilize it so that it could support the growth of vegetation.
Soil nailing is a construction technique that allows the safe over-steeping of new or existing soil slopes. Soil nails hold the deeper structure of the bank together, but do nothing to help the surface grow vegetation because you can’t keep topsoil on there. That’s where ToughCell® came in. The solution to our problem was the ToughCell®, essentially a little cup that holds the topsoil in place. The ToughCell® were then hydro seeded, which is a fancy way of saying they spread grass seeds. This creates the optimal environment for trees to root and create a better surface-holding arrangement. Then, the trees will be able to dig deeper into the slope and create a more permanent solution for holding surface arrangements.
The Paradox Difference
When we started this project, we knew we had to be able to create a solution that was as durable and long-lasting as the Alberta terrain itself. We knew this endeavour would be a challenge—but we’d be lying if we said it wasn’t totally worth it.
We took the same basic idea behind geocell technology but instead opted to use ToughCell®. We wanted to create something that could stand up to harsh conditions in a way unique to Paradox Access Solutions, and ToughCell® was the way to go.
Our collaborators said they had filled HDPE geocells in considerable differences on slopes that weren’t as severe. For a project like Grierson Hill, though, something different was needed. HDPE geocells would stretch, move, and entirely change their shape as weight is added, but our ToughCells® were static, meaning the material wouldn’t stretch. They were built where they would stay long-term, adding longevity to the project in a way that’s unique to Paradox Access Solutions.
Tough Cells® maximize soil confinement and drainage while preventing runoff by distributing load evenly throughout the material. Because they’re so stable, Tough Cells® can be used in various projects, like Grierson Hill, where long-term stability was needed.
Their proprietary technology ensures equal load distribution and reinforces the infill material of low-strength and easily-sourced aggregates such as sand, local soils or recycled materials. Tough Cell® Geocells are fabricated from a new Novel Polymeric Alloy called Neoloy®; developed explicitly for geocells that have been found superior to any other geocell or cellular confinement product. This is why we knew that no other product would work and why Tough Cell® has been trusted by Paradox for years.