CVN Dry Dock No. 6 Floor Repairs Soil Stabilization by Compaction Grouting Bremerton, Washington Back to Project List Real Time Monitoring Low slump compaction grout is placed for soil densification in the deep dry dock facility. Project Overview: Drydock No. 6 is a 1,180 feet long, 180 feet wide and 61 feet deep facility built in 1962. An area of poorly compacted and/or eroded soil beneath the dry dock slab caused settlement and damage to the slab, and precipitated the need for repairs. Layne GeoConstruction drilled a total of 556 holes and utilized a sophisticated computerized system to monitor the volume and pressure of the compaction grouting operation. Prior to compaction grouting, each hole was cored through an extensively reinforced (#9 and #10 rebar), 7 feet thick concrete slab. Ground penetrating radar was used to locate the rebar to minimize damage to the integrity of the slab. Once cored, the base of the slab was examined for voids greater than 1 inch. Voids measuring greater than 1 inch were documented by video and then the voids were grouted prior to compaction grouting. Compaction grouting ranged in depths from 27 to 35 feet. Over 1,600 cubic yards of compaction grout were placed. Extensive structural monitoring of the slab was performed during all grouting operations. All grout was mixed with a batch plant on the floor of the dry dock, requiring detailed logistical coordination for bulk materials handling, movement and placement.     Value of Work Performed: $2,300,000 Project Duration: 3 1/2 months Project Completion Date: April 2006 Project Reference: General Contractor: NOVA Group, Inc. Dan Fox (707) 265-1119