Masonry Magazine February 2003 Page. 31
As the units became known in the local market, word traveled and interest grew with inquiries generated from several other concrete products companies in Canada. "We only wanted to be careful that no one within 50 miles of our plant was making the same system," claims Risi. "At that time, we didn't even think about licensing the system."
That changed in 1982 when Risi licensed the concept to others. Not to be outdone, Risi added new sizes, appearances, and even functionality to the Pisa Stone idea, always maintaining the basic principles from the original. And he tracked the market carefully, watching for other ideas to expand the company and market.
One of these was the Dura Crib system. Patterned after the landscape timber or railroad tie retaining wall, these concrete structural beams combined facing units with reinforced tie-backs and were used in a crib form that had the overall effect of a large gravity wall. More durable than wood, these systems are popular with landscape architects and engineers.
The next step was the Pisa2 block. These were developed in response to a need for greater flexibility in designs for walls, both in structural and landscaping applications. These blocks provide the same stability with the added benefit of being able to accommodate tight radii and the "snaking" wall geometry that is popular in many parts of the world.
The idea of solid, high-strength concrete units that interlock with a continuous tongue and groove to form a flexible, stable dry-stacked retaining wall system might seem simple now, but in the late 1960s, it was unheard of.
we hold up banks
The Solid Choice
RomanPisa®
and your reputation.
RisiStone retaining wall systems www.risistone.com 1.800.626.9255
The Voice of the Mason Contractor CIRCLE 178 ON READER SERVICE CARD February 2003 Masonry 29 Ris Stone Syзлита 2002