Deltaport Berth’s 3 Design and Construction Challenges

Port Metro Vancouver, located in the southwestern corner of British Columbia, is Canada’s largest port. Deltaport Container Terminal, at Roberts Bank just south of Vancouver, opened for business in 1997 and was an immediate success. In response to increased demand and growth forecasts Port Metro Vancouver, in partnership with the terminal operator (Global Container Terminals), decided to extend the two-berth caisson wharf and expand the container terminal to increase annual throughput by 50% from 1.2 to 1.8 million twenty-foot equivalent units (TEUs). This paper will focus on some of the unique aspects of the design for the Deltaport Berth 3 expansion, and resolution of key challenges encountered during construction. Concrete caissons for the wharf extension were prefabricated off-site, towed to site, and then installed at super-elevated positions to compensate for anticipated differential settlements and rotations due to the added mass of the terminal reclamation fills. This elevation pre-set provided a precisely aligned wharf extension, smooth alignment of crane rails and a level apron pavement. A risk based approach was used to develop appropriate seismic design criteria for the main wharf and for the ship-to-shore crane rails. Displacement-based seismic criteria were used for the design of this concrete gravity caisson wharf. Marine vibro-densification of the crushed rock foundation fills, combined with vibro-replacement and dynamic compaction of apron backfill materials, were methods used to improve the bearing capacity, seismic resistance, and settlement performance. A fill management plan was implemented for placement and preloading of reclamation fills in the terminal area, optimized to use all preload material as backfill. Wave protection for the Deltaport tugboat facility was provided by a tied sheet-piled bulkhead, as a temporary measure during berth construction. The design philosophy for the north end closure wall for the wharf extension, was based on the consequences of overall wall integrity and rupture of individual elements. Significant difficulties were overcome during construction of these sheet-piled walls.