Schematics of Loading and Boundary Condition Boxes (LBCBs)
Each LBCB provides six degree-of-freedom control and consists of a reaction box, six actuators (960/1459 kN tension/compression) and a loading platform. The overall dimensions of the reaction box are approximately 3.6 m long, 1.8 m wide and 1.8 m high. The loading platform is approximately 2.7 m long and 1.2 m wide. Three vertical actuators are used to control the z, theta-x (roll) and theta-y (pitch) position of the loading platform. Each of these actuators is anchored to the base of the reaction box and attached to the underside of the loading platform. Two horizontal actuators that are attached to the end of the reaction box are used to control the x and theta-z (yaw) position of the loading platform. One additional horizontal actuator is used to control the y-direction position of the loading platform. Pillow Block Spherical Bearings have been selected so that the motion of the loading platform is not unduly restricted in any of the six degrees of motion. The LBCBs are uniquely designed to be portable so that they can be anchored on any reaction structure that has a compatible arrangement of anchorage holes. This design facilitates the use of the LBCB at the Geotechnical Testing Site in Rantoul, Illinois.