In this invention, after a hole has been drilled or excavated, injection probe(s) are placed at appropriate depth(s), the excavated native materials are replaced with appropriately sized crushed rock or other natural or synthetic materials, and then a polymeric resin is injected through the probe(s) to encapsulate and bind the fill material, whereby upon curing the polymeric resin and fill material forms a foam friction pile. Such friction piles drilled or excavated adjacent to each other will form a foam sheet piling system. The foam piles can also be re-enforced using nylon, polypropylene, fiberglass, other synthetic or non-synthetic materials or combinations of these materials. The polymeric resin typically would comprise a high density closed cell, water resistant expanding two component polyurethane foam system.