Lymon C. Reese

A Design Method For an Anchor Pile in a Mooring System

This study was directed toward resolving the problem of insufficient holding power experienced by ships anchoring at locations where the bottom consists of soft soil. A procedure is described by the authors for the design of a pile in soft clay to provide an anchor for a moored vessel. Behavior of a pile under lateral loading and axial loading and the interaction of an embedded chain are examined. A method is presented for computing the angle of incidence of the anchor chain with the pile, and theories are presented for computing the behavior of the pile under the aforementioned conditions. The procedures outlined in this paper can be applied to compute the dimensions of the pile and optimum positioning of the chain bracket along the pile. An example problem is presented and discussed to illustrate the procedure. Based on a number of experiments concerning the behavior of piles under axial loading and lateral loading, the authors conclude that these portions of the problem can be solved with reasonable accuracy. The authors recommend that the analytical procedure can be improved if such a mooring system is instrumented and data are obtained on the field behavior of the components of the system.