Solve Challenges Across Soft Sub grades.
Hwy 881, Encana By-Pass Road AB, Canada
Project Background and Challenges
In late 2016, Harvest Energy’s construction consultant, Drifter, was faced with rehabilitating and upgrading an existing access road to handle the rigors of a new plant expansion and commissioning. The modifications were being made to Harvest Operations Black Gold In-Situ Thermal SAGD plant located south of Conklin, AB. The existing Encana By-pass road was 11.5 KM (7.1 Mile) long and, originally served as a secondary access road into the facilities in the region including Cenovus Christina Lake, Devon Pike, Jackfish and Kirby.
The access road had not been in use for several years and became almost impassable during spring and summer rain events due to neglect. Harvest Energy turned to Presto Geosystems’ Canadian distributor—and well-known geosynthetics supplier/installer in the region-Layfield—for load support options to drastically improve the performance of the road.
Keeping the road operational during initial subgrade preparation and staging of reinforcement material and gravel in advance of the road being closed for repairs was a concern. Work also needed to be completed on a short construction timeline. Layfield’s execution plan called for the road to be closed for less than 2 weeks.
Building of a Reinforced Road
The decision was made to deploy the Presto Geosystem GEOWEB® 3D load support system with Mirafi’s enhanced woven geotextile. The materials were chosen due to their performance and speed of deployment. Several sections of the access road were in such poor condition that a second layer of GEOWEB®/geotextile for additional sub-base reinforcement would likely be required.
How Does the GEOWEB® 3D System Work?
To combat soft subgrade challenges, roads built with GEOWEB® 3D geocells, geotextile reinforcement and aggregate infill are extremely stable and well-equipped to support heavy traffic.
- Low-maintenance, 3D confined aggregate surface is highly resistant to rutting and requires virtually no maintenance.
- Lower-cost, local fill may be used
- GEOWEB panels and geotextile rolls are easy to deploy and install, even in remote or difficult-access locations
- The surface is ready for traffic immediately after infilling and compaction
Fast, All Weather Installation
A key to installation speed was the use of the patented ATRA® Key device to connect GEOWEB® panels. The corrosion-resistant keys are the strongest and safest connection method–dramatically speeding deployment of the GEOWEB® panels.
The road is now in service awaiting final plant commissioning in early 2019.