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The Pier E Redevelopment Project targets reconfiguring and combining two irregularly shaped adjacent container terminals to establish a more efficient and environmentally friendly facility. This project aims at replacing the existing wharf structures with modern structures over wharf slope areas stabilized by rock dike revetment or ground improvement. Also, the existing Pier E wharf will be rehabilitated and widened to accommodate a 137’-9” gauge crane, and eventually extended to the south to connect with the wharf at the Pier F terminal. The wharf layout consists of a 4,250-foot long berth composed of 6 wharf segments separated by transverse expansion joints. The design of the wharf considers variation in soil properties and proposed wharf slope stabilization solutions at the different wharf segments. This paper addresses the wharf structural design consierations. A performance based approach was used for the seismic design of the wharf structure for inertia and kinematic loading. The design philosophy objective is to provide a ductile structure with plastic hinges forming in the piles to dissipate the earthquake energy. A series of non-linear static pushover analyses that consider the nonlinear soil behavior were performed to evaluate the structure’s displacement capacity and shear demand. The substitute structure method was used to calculate the seismic displacement demands for three levels of ground motions. A non-Linear Time History Analysis was performed for the linked wharf units to verify the displacement demands and determine shear key forces. Pier E utilizes a wider gauge crane with a higher vertical load and translational elastic period of the mode with the maximum participating mass being about 1.3 to 1.5 seconds. The wharf seismic design considered the crane mass impact on the wharf displacement demand.

A major project is underway at the Port of Los Angeles (POLA) that proposes to create approximately 35 acres of land and water for a world-class marine research institute. Approximately 2,540 ft of existing wharves at Berths 57-60 will be upgraded in Phase 1. This is the oldest wharf built in San Pedro Bay and the existing wharf and the shed have been designated as “historic.” This designation requires preservation of the exterior appearance of the shed as well as a visible portion of the wharf located above water. Additionally, POLA is located in a highly seismic area and the proposed project allows public access, thereby requiring any upgrades to meet current building codes. Initial evaluations indicate significant improvements are needed to meet current seismic requirements in addition to repairs for the proposed project. This paper discusses the seismic, structural, and geotechnical aspects of the project and compares various upgrade alternatives considered for implementation.

During the magnitude (Mw) 7.7, 1993 Guam earthquake, which caused significant damages to coastal structures throughout the area, X-Ray Wharf in the island showed signs of liquefaction and lateral spreading and seismically induced settlement up to 30 cm. The existing wharf is approximately 450 m long and consists of a combination of steel sheet pile bulkheads with a single level of tie-backs and steel sheet pile bulkheads with relieving platforms. Even though the damage to the wharf was not significant during the 1993 earthquake, it was found that the existing wharf would not meet the current two-level seismic performance criteria per the latest unified facilities criteria, (UFC) 4-152-01 (DoD, 2005, 2012). Among the various concepts evaluated to upgrade the existing wharf, constructing a new wharf in front of the existing wharf was found to be the most effective solution and taken forward for final design. A new sheet pile bulkhead wall approximately 10.7 m away from the existing sheet pile bulkhead will be constructed and the space between the new and old sheet pile bulkheads will be filled with improved granular backfill. Cement deep soil mixing (CDSM) was selected as the most cost-effective ground improvement technique to improve the granular fill and weak foundation materials. Construction of the new wharf is presently under way. The paper discusses the seismic design philosophy, geotechnical field investigation, site characterization, seismic analyses, and ground improvement design in an informative manner useful to practicing engineers.