Limit State Behavior of Base Isolated Structures: Base Isolated Moment Frame with Impact on Concrete Moat Wall

This experiment was conducted to investigate the effects of pounding on a base isolated moment frame. Concrete moat walls were placed between 4 and 6 inches from the base of the structure. Different moat wall thicknesses were also tested to see the effects of wall stiffness on the structural response. The wall thickness varied between 2 and 6 inches. The moat walls were filled with sand to simulate the soil backfill. Concrete blocks were attached to the base of the moment frame structure for impact with the moat walls.
First, a 2" thick moat wall was placed at a 6" gap distance. Then the moat wall was flipped around to 4" thick at the same distance. For the last 8 trials, a new moat wall 6" thick was placed 4" from the base of the structure.