This Patented technology was ostensibly developed for northern climes where perma-frost is a reality and where infrastructure is often constructed above grade on piers.
The Polymer Pile concept is a methodology of backfilling around the pier that would support a structure above ground. A hole is drilled to a specified depth, filled with a granular material (gravel) and injected with our expanding hydro-insensitive expanding polyurethane resin. As the resin expands, voids between the granular spaces are filled and a controlled mold pressure is exerted to completely bind the gravels within the confined space of the bored hole and surrounding the pier within the hole with resultant break points exceeding 1600 psi. for the back-filled conglomerate. It is of note that the process to set up and cure literally only takes minutes before work on the piers can continue. Additionally, cold weather does not impact the reaction of the polyurethane system. Although the polyurethane system is exothermic in its reaction the amount of heat generated in the process is so minimal that it does not contribute to melting of perma-frost, ice or ice lens’ as the total amount of heat energy within the foam generated is minimal
Testing undertaken at the University of Alberta and stated in an Engineering Masters Program Thesis confirmed,” The foam will travel readily through a gravelly medium and produce a concrete equal in strength to light weight Portland cement concretes. The foam injection can be customized to achieve the best quality product for specific environmental conditions. The mechanical behavior fulfills the requirement of being stronger than native frozen soils (0.5 – 1.0 MPa).”
It is also noteworthy that pile like structures can also be created in granular unfrozen soils to provide support, densification, by simply drilling to the desired depth and injecting the polyurethane system which binds the base soils together.
The drilling procedure tends to loosen the base soils as a result of the hammer-drill action and allow the polyurethane material to permeate the base soils with pile like structures typically measuring some 14” – 20” in diameter. This process has been used in creating shoring systems to prevent sloughing of granular base soils.