Three research tasks are proposed to investigate issues of concern in the earthquake behavior of concrete dams: opening and closing of contraction joints in arch dams, nonuniform seismic input, and cracking in gravity dams. The first two tasks are computer studies and will result in significant enhancement of the computational capabilities available to practicing engineers. The shaking table tests on model gravity dam monoliths will provide insight into the crack propagation mechanism as well as the dynamic stability in the presence of cracks. These tests will be conducted on a small, high-frequency shaking table which was recently donated to Caltech. An additional research task for the future, the reservoir sediment experiments will be conducted in actual reservoirs and are designed to provide information on dynamic water-sediment interaction about which little is presently known.
