MARC Train Service Extension Maryland Transit Authority Frederick, Maryland Back to Project List Limited Mobility Grouting Compaction grouting provides soil stabilization beneath a section of proposed high-speed rail. Project Overview: Layne GeoConstruction stabilized the rock and soil below a to-be-constructed portion of high-speed rail, as part of the Maryland Mass Transit Administration’s upgrade of outdated rail lines. The karst limestone underlying the track is prone to sink holes and compaction grouting filled the voids and consolidated the soils. In total, 75,000 linear feet of grout holes were drilled and 6,600 yards of compaction grout were placed. Alternating lines of drill holes were installed into soil and rock, parallel with the track centerline. A low slump compaction grout consisting of cement, flyash, sand and water was then placed, and laser levels were used to monitor grout heave. A total of 3,500 linear feet of track sub-grade was treated.     Value of Work Performed: $2,200,000 Project Duration: 11 months Project Completion Date: November 2000 Project Reference: General Contractor: Haverhill Contracting Company, Inc. Steve Beckley (410) 388-1400