Seismic Design of Anchored Bulkheads: The Geotechnical Perspective

Geotechnical design of anchored bulkheads is largely dependent on the static and seismic increment of active lateral earth pressures acting on the bulkhead, and the lateral resistance provided by the passive earth pressure and anchor systems. The geotechnical design approach for bulkhead design under earthquake conditions has historically been based on approaches developed for dry, uniform soils, rigid walls, or piles, with adjustments intended to account for wall flexibility. Considering the limitations associated with these historical procedures and the widespread adoption of performance-based seismic design principals in contemporary port practice, the ASCE COPRI Task Committee for Seismic Design of Bulkheads has reviewed existing design methods and developed a supplemental approach that supports the need for deformation-based seismic design of anchored bulkheads. This approach will be part of a new guidelines document for seismic design of anchored bulkheads. This paper summarizes the strengths and weaknesses of current seismic design methods, and provides suggested practice-oriented, force- and deformation-based analysis approaches for use by geotechnical engineers. A companion paper will discuss related structural design issues. The guidelines are anticipated to be published in early 2020.