A relieving platform was designed to support self-propelled modular transport (SPMT) traffic across the quay wall at Berth 309. The SPMTs hauls approximately 300-ton fabricated units. Each SPMT weighs approximately 60 tons. Two SPMTs side by side are required for each 300-ton fabricated unit for a total load on the platform of 420 tons. The relieving platform supports the SPMTs such that large surface surcharge loads do not affect the existing circular cell bulkhead wall (quay wall) when equipment is launched from the berth onto Drydock #5. Micropile foundations were installed provide foundation support of the relieving platform. GRI conducted cone penetration test (CPT) explorations and completed laboratory testing and engineering studies to develop recommendations for design and construction of micropile foundation support.

Location: Portland, Oregon

Owner: Vigor Industrial, LLC

Market Sector: Ports & Waterfront

Services: Geotechnical Engineering, Laboratory Services