Helical Anchors for Bridge Abutments

The Winslow Geo Anchor was recently used for the foundation of a 70-foot bridge (H20-44 loading) in Walnut Creek, California.

The span crosses a large stream, enabling the development of two prime hillside lots previously restricted due to the inability of transporting materials from one side to the other. 14 anchors were used in the foundation -- seven on each side -- instead of 20 piers initially architected. The structure will easily meet the 37-ton load (enough to support a county fire engine) requirement, as each anchor has been tested at 50 tons capability.

Jim Winslow, director of deep foundations at Best Base noted, “Not only did our anchors save a considerable amount of money in materials because we used significantly less concrete and no cages/caissons, but the anchors were installed in one day vs. the one week estimated for the concrete piers -- saving a huge amount in additional labor costs.”

Rick Kolby, principal of the group developing the project, Tice Valley Partners, said, “In addition to the nearly 50% we saved in materials and labor, the Winslow Geo Anchor had no impact on the stream itself. It was easily installed, is environmentally friendly and extremely structurally sound -- factors made the code and review process easy. In essence, we were able to provide a much better look and feel to the entire area, and that will be a huge benefit as the years go by and future households enjoy the residences.”