Rosetta Creates Tall Walls in Just 6 Days

THE CHALLENGE

A high-end development requires a landscape to match, but achieving a truly beautiful landscape in a very limited space takes creativity and innovation. The developers of the new Amica at London retirement community were faced with just such a challenge as they began construction on a new facility and grounds in 2010.

The area behind the development was designed to have a lawn and garden landscape that could be enjoyed by residents. However, a steep slope at the back property line severely limited space, while a stormwater drainage channel cut right through the middle of the site. The goal of the project was to create an aesthetic design for the landscape that incorporated the drainage channel while maximizing usable space.

THE SOLUTION

To achieve this goal, the first step was finding a way to stabilize the bank in an aesthetic way. To provide enough space for the yard, a wall needed to be built directly on the property line. However, a conservation area was adjacent to the property, making a geogrid-reinforced or tiered wall impossible.

Engineers from Aecom London Inc. considered several different options including a cast-in-place concrete wall before designing a 14 feet (4.3 meters) high sheet pile wall to retain the soil. To achieve the aesthetic finish the project required, Amica chose Rosetta Hardscapes' Outcropping Collection walls from Brown's Concrete to face the sheet pile wall.

The Rosetta Outcropping Collection is a structural retaining wall system that accurately achieves the look and feel of natural outcropping stone. By creating Rosetta using wetcast concrete, walls achieve a natural look unattainable by dry cast products. Rosetta's Outcropping Collection uses 12 unique size units with 24 unique stone textures. Dimensions vary from 24 inches (610 millimeters) to 72 inches (1829 millimeters) wide and from 6 inches (152 millimeters) to 24 inches (610 millimeters) tall.

These relatively large dimensions give walls a natural, believable finish. Outcropping walls can be engineered and reinforced to create tall, structural retaining walls but in this application, the designers chose Rosetta to act as an aesthetic face for the structural sheet pile retaining wall because there simply was not enough room to build a reinforced Outcropping wall on site.

The installation of the Rosetta portion of the project progressed very quickly. Groundmasters, Inc. had scheduled 2-3 weeks to install the project, but ended up completing the installation in only six working days.

"It was very tight quarters. It was over a stormwater channel, so it all had to be put in with a crane," explained Gary Lima, owner of Groundmasters, Inc. "The product is pretty easy to put in, and we installed it on a concrete leveling pad, so we didn't have to mess around with preparing a base. It's one of those jobs that just went really well."

In ordinary Outcropping walls, shear heels on the back of each block provide a mechanical connection between units, but for this wall, some of the shear heels needed to be removed to achieve the necessary wall batter. The lifting hook on the back of the Outcropping block was then fastened to the sheet pile wall using re-bar. This is analogous to ties being used to secure brick to a building structure. The end result was a truly unique engineering feat.

THE OUTCOME

The Rosetta Outcropping Collection allowed engineers to create a beautiful, unique wall that the residents of Amica enjoy on a daily basis.

PROJECT DETAILS

Project Name: Amica At London Walls Customer Name: Amica At London Design Engineer: Aecom London Inc. Block Manufacturer: Brown's Concrete Products, Limited Wall Installer: Groundmasters, Inc. Project Location: London, Ontario Year Built: 2010 Case: 002 - Amica At London Walls