Seismic Design of Anchored Bulkheads: The Structural Design Perspective

This paper provides a detailed discussion on the structural design recommendations and methodologies to be presented ASCE COPRI Manual of Practice for the Seismic Design of Bulkheads (SDB). The manual will be published in early 2020. The use of limit equilibrium design methodology is prevalent in the current state of practice. However, this methodology does not provide accurate bulkhead deformation, associated upland deflection, and resulting impact on the infrastructure retained by a bulkhead. Therefore, it is necessary to rely on design methodologies such as pseudo-static non-linear soil spring analysis. This methodology considers the non-linear behavior of the soil (passive resistance mobilized with varying deflection), resulting force distribution and deflections, thereby providing a means for performance evaluation. The SDB Task Committee has developed a coherent set of design recommendations based on detailed review of available references and current advances on pertinent topics. These include discussion on performance limits, allowable stresses, embedment depth calculation, P- delta effects, and structural detailing. The recommendations are developed in conjunction with geotechnical design experts to harmonize the overall design process. Separate, companion papers will discuss related geotechnical design issues and an idealized case study demonstrating the methods to be outlined in the manual.