Dewatering Cofferdam for the Trident Submarine Drydock.
Abstract
The dewatering cofferdam for the TRIDENT nuclear submarine drydock at Bangor, Washington, presented many challenges. These included water depths up to 25 meters, artesian pressures 10 to 13 meters above mean sea level, difficult pile driving conditions, and the potential for seismically induced liquefaction of the fill in the cofferdam cells. Design ground motions of 0.15 g dictated that fill densities exceed 75% density index. Deep compaction was achieved using a large vibratory probe. Inclinometer, strain gage, and optical survey measurements on the sheet piles and extensive piezometric data was obtained. Significant observations were that (1) deep cell compaction can markedly increase fill density without increasing lateral cell pressures unduly, and (2) maximum interlock tension may be well below the one-quarter height of exposed sheeting as often assumed in design. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1982
- Accession Number
- ADA120023
Entities
People
- J. B. Forrest
Organizations
- Naval Facilities Engineering Service Center