The Laboratory has three biaxial shake tables in operation. Manufactured by MTS, each table measures 14 x 14.6 ft (4.3 x 4.5 m), has a stroke of ±12 in (± 300 mm), and can reach a peak velocity of 40 in/sec (1000 mm/sec) and an acceleration of 1g with a 50 ton payload (445 kN).
All three tables can be constrained to act together as a single large table, or they can be operated individually with independent motions.
NEES@Nevada recently added a fourth shake table referred as the 6-Degree-of-Freedom (6DOF) table to complement our existing three biaxial shake tables. The fourth table is a true 6 degrees of freedom system, with three translational and three rotational components. The system, except for the seismic controller, was designed in-house by Patrick Laplace as a light-weight, high-performance shake table primarily targeted for experiments involving vertical excitation including but not limited to seismic qualification testing.
The table is comprised of a 10ft x 10ft (3m x 3m), 7-ton platen and can carry a nominal payload of 50 tons (445 kN) at 1 g acceleration in all axes. The X,Y,Z displacement strokes are±12, ±12, and ±4 in (±305, ±305, and ±105 mm) respectively. The system uses a total of eight MTS actuators.
All tables are run using MTS 469D seismic controllers, which are integrated into the laboratory computer network through ScramNET reflective memory. All tables may be relocated to allow a large variation of experimental configurations. It is possible for all four tables to be operated synchronously or asynchronously.