7th Street, Nisku, Alberta
This industrial area, under the jurisdiction of the County of Leduc, continually experiences heavy commercial truck loads. CALL FOR QUOTEYear
2012
Client
Leduc County,
Canada
Overview
The Nisku community is located approximately 25km south of the City of Edmonton and lies adjacent to the Edmonton International Airport. This industrial area, under the jurisdiction of the County of Leduc, continually experiences heavy commercial truck loads. The County desired to find innovative solutions for building stronger pavement structures that would rehabilitate and extend the service life of their road network. The University of Alberta’s Department of Civil Engineering in Edmonton conducted a research study to compare the performance of a cement-treated base (CTB) versus a Tough Cell® Geocell-stabilized road base. This project was instrumental in establishing quantitative data to clearly illustrate the properties, differences, advantages/disadvantages, and most importantly, the long-term performance of specific pavement reinforcement methods. Each method was employed in a 500m-long section of the same road and we’re both monitored over winter seasons to evaluate structural performance.
Year
2012
Client
Leduc County,
Canada
Overview
The Nisku community is located approximately 25km south of the City of Edmonton and lies adjacent to the Edmonton International Airport. This industrial area, under the jurisdiction of the County of Leduc, continually experiences heavy commercial truck loads. The County desired to find innovative solutions for building stronger pavement structures that would rehabilitate and extend the service life of their road network. The University of Alberta’s Department of Civil Engineering in Edmonton conducted a research study to compare the performance of a cement-treated base (CTB) versus a Tough Cell® Geocell-stabilized road base. This project was instrumental in establishing quantitative data to clearly illustrate the properties, differences, advantages/disadvantages, and most importantly, the long-term performance of specific pavement reinforcement methods. Each method was employed in a 500m-long section of the same road and we’re both monitored over winter seasons to evaluate structural performance.
Challenges
The industrial area of Nisku in the County of Leduc experiences heavy truckloads which expose pavement structure to excessive damage, with the exponential growth of similar traffic expected in coming years. 7th St. is a two-lane road with rural geometry serving as the access road to numerous heavy industrial businesses in Nisku and is bisected by railway track. The existing road was in very poor serviceability condition. The County elected to reconstruct the sections to the north and south of the railway with two different base pavement structures. The University of Alberta agreed to conduct field monitoring, data analysis, and a report for this project.
Heavy Truck Loads
This road would support a constant influx and outflow of heavy equipment traffic, meaning the property needed to be developed to withstand a serious beating.
Railway Bisection
This road bisects a major railway that sees a lot of activity that plus the constant flow of heavy equipment traffic, meant that the property needed to be developed to withstand a serious loads
Winter Temperatures
In Alberta, drastic temperature swings are common and must absolutely be taken into consideration during planning. Thaw/freeze cycles wreak havoc on structures such as concrete pads and asphalt, which aren’t designed to withstand heaving or frost boils during winter/spring. Similarly, un-stabilized pads won’t hold up through summer rains and heavy rutting without some form of subbase stabilization.
Our Approach
Existing road materials were recycled using a milling machine and used to form the sub-base of the new road.
LAYERS
A layer of woven geotextile was placed as a separator between the subbase and a 200mm subgrade layer in the north section between the railway and 15th avenue followed by a 150 mm layer of Tough Cell® geocells infilled with new granular material.
CTB
In the south section, a 150 mm Cement Treated Base (CTB) consisting of approx. 16 kg/m2 of cement mixed with recycled base material as per typical pavement construction in Nisku) was used over a 300mm subgrade.
The road utilized two layers of Tough Cell®, while the pad utilized three layers of Cells. Both were filled with local materials while aggregates were supplied by local quarries, within ±30km radius.
The road was 4.3 kms in total and finished with a width of 8 meters The Pad was 210m x 195m (40,950m2)
Aggregate materials required are significantly less than conventional methods, due to eliminated requirement for excavation and replacement of organic materials. This resulted in a huge carbon savings usually incurred through expensive excavation & hauling of aggregate material.
Results
The demonstration comparing cement stabilization and Tough Cell® has been
monitored since the completion of construction in 2012. In spite of the heavy traffic on the road, there is no sign of failure or any other distress in the Tough Cell® Geocell section and the road is performing without problems after five years of operation. This project served as a substantiation of the technology and its acceptance by the Alberta Ministry of Transportation.
Total area: 500m x 8m
Product(s): 330-150 Type B Tough Cell® Geocell; woven geotextile.
Infill: 20mm granular base course (GBC) with the protective cap of 50 mm granular fill
Completion: 65 mm HMA riding course
Benefits
REINFORCING THE GROUND WITH TOUGH CELL
As of April 2015 and experiencing the projected heavy traffic levels, there was no sign of failure or other distress in the Tough Cell® reinforced section, in contrast to both transverse and longitudinal cracking evident in the comparative CTB section as early as June 2014.
It creates the “Beam Effect”
It can be used in temperatures ranging from +60°C to –60°C
The product carries a 75-year guarantee.
It can easily be reclaimed and is recyclable.
SECURING STEEL-FRAMED MATS
The road is still under observation after 5 years and is-expected to deliver the desired longevity of service life to the County
It reduced project costs.
Reduced maintenance
