LABORATORY EXPERIMENTS OF TSUNAMI RUNUP ON A CIRCULAR ISLAND

Laboratory experiments of a 7.2-m-diameter conical island were conduct ed to study three-dimensional tsunami runup. The 62.5-cm tall island h ad 1 on 4 side slopes and was positioned in the center of a 30-m-wide by 25-m-long flat-bottom basin. Solitary waves with height-to-depth ra tios ranging from 0.05 to 0.20 and ''source'' lengths ranging from 0.3 0 to 7.14 island diameters were tested in water depths of 32 and 42 cm . Twenty-seven capacitance wave gages were used to measure surface wav e elevations at incident and four radial transects on the island slope . Maximum vertical runup measurements were made at 20 locations around the perimeter of the island using rod and transit. A new runup gage w as located on the back or lee side of the island to record runup time series.