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Propex GeoSolutions, www.propexglobal.com, 800.621.1273
MSE Wall
In 2019, Edgewood Middle School underwent renovations and expansion, including construction of a new parking lot. To utilize the available property, a retaining wall was needed to create enough level surface area for the parking lot. Initially, a modular block wall was considered, but the landscape architect designing the project wanted to find a more aesthetic and cost-effective solution.
A geotechnical evaluation was conducted to determine recommended soil strength parameters for the Mechanically Stabilized Earth (MSE) Wall. Based on the information provided, Propex GeoSolutions was able to analyze the wall and determine that PYRAWALL, an engineered wrap-faced vegetation solution, would effectively stabilize the area and protect it from future erosion.
The PYRAWALL system consists of PYRAMAT 75 High Performance Turf Reinforcement Mat (HPTRM) and fiber-composite internal bracing. Additional primary reinforcement can be incorporated within the engineered wrap-faced vegetation solution lifts to provide greater embedment depth and achieve greater wall heights. All materials in the system are environmentally inert and resistant to corrosion. Once installed, it produces a reinforced soil mass to resist lateral earth pressures and provide immediate erosion protection. It is also designed to encourage vegetation and is a vegetated best management practice solution for National Pollutant Discharge Elimination System (NPDES) Storm Water Compliance.
The engineered wrap-faced vegetation solution is constructed in one foot high lifts that are filled with onsite or imported fill, depending on the project design. The Edgewood project used eight lifts to raise the grade of the wall high enough to accommodate the new parking lot. Because of the system’s flexible nature, curves can be incorporated along the wall or slope alignment. For this installation, a nearly 90-degree turn was incorporated into the design.
In addition to providing immediate and long-term erosion protection, PYRAWALL is more cost effective than hard armoring solutions. It is shipped with the internal bracing preinstalled, making construction easy and reducing labor costs. Plus, it is engineered to promote rapid vegetation for an aesthetically pleasing result. Four months after construction, the PYRAWALL at Edgewood Middle was fully vegetated.
