Collision tolerant pile structure

摘要

A support pile assembly for an aid to navigation that is to be placed in an area where it will be subject to repeated hits by boats and barges. In one configuration the assembly comprises a foundation which is driven into the mud on the bottom and which receives the support pile, and the support pile, which slips into the foundation. The support pile comprises three sections: a lower section which fits in the foundation; a spring section that is attached to the lower section by means of a joint in such a way that it cart flex in all directions; and an upper section, rigidly fixed to the spring section, to which the aid to navigation is attached. A compression spring in the spring section gets compressed whenever the pile is hit by a ship or barge and forced out of its normal vertical position; as the spring extends back to its original length, it causes the pile to revert to the vertical position. A second configuration is the same as the first except that the foundation rests on the bottom and the support pile comprises only the spring section and the upper section. The joint is bolted onto the base rather than onto the lower section as in the first configuration.