Traditional methods for anchoring small structures such as towers have been accomplished with the use of cables and deadman anchors. Excavation, carpentry, concrete & reinforcing steel skills, and equipment/material access are all required to provide a safe installation for the deadman anchors. Many locations are remote and have environmental and/or excavation limitations due to presence of trees, shallow bedrock, streams, and/or cut slopes. For deadman anchor installation a large surface area needs to be cleared and excavated, which is not always possible. A Mid-Atlantic state’s Department of Transportation had a swinging anchor bridge requiring
anchors with a working design load of 21 tons per anchor. The bridge was only accessible through a ford when the water levels in the stream were down. The presence of shallow shale, siltstone and sandstone with little overburden made galvanized Self-Drilling SuperMicropiles™ an ideal option. GeoStabilization International® provided a design/build/warranty anchor system comprised of galvanized Self-Drilling SuperMicropiles™ of up to 30 feet in length. This included sacrificial nails for verification testing purposes that were tested to 42 tons – 200% of the design load.
Swinging Bridge Anchors, Virginia Department of Transportation