GTA has provided drilling, geotechnical and environmental consulting, and construction observation and testing services for numerous projects at Aberdeen Proving Ground.
For this project, GTA provided drilling services for the new 400’ x 100’, 20‑foot‑deep, excavated pond with a 6-foot wave machine for testing amphibious vehicles for beachfront assaults. GTA services included subsurface explorations and preparation of geotechnical recommendations, cost estimating, design of a 32-foot-high, reinforced earth retaining wall, and slope stability analysis for the dynamic forces imposed by underwater charges of up to 500 pounds of TNT equivalent. Piezometers were installed prior to design, to depths approaching 50 feet, to evaluate groundwater levels. Piezometers were also installed after construction to evaluate the effect of explosives testing on the level of subsurface water.
Installed instrumentation paddles containing electronic transducers and other sensors specifically designed and manufactured to evaluate the forces on the soils below the pond during explosive testing. The paddles where installed with a truck-mounted drill rig mounted on a barge.
Worked directly with APG engineering staff to design a “bayonet” style installation system that allowed the drill string to be disconnected from the instrumentation paddle after it was installed to the proposed depth below mud line.