Sloshing Analysis of Rectangular Water Tanks : Flexible Roof Sloshing Impact and Yawing Sloshing

Earthquake responses of rectangular water tanks should be investigated to keep water during disaster. Roof damage of rectangular tanks was reported in Hanshin Great Earthquake. In order to study sloshing impact effects on elastic roof plates, a sloshing test of using a multi-axes shaking table was conducted. In the test, the sloshing impact was measured in three roof conditions. The roof plate of 3 mm thickness was used in two setting conditions. One was clamped with bolts, the other was clamped with bolts and rubber washers. The roof plate of 13 mm thickness was clamped with bolts. Large roof deformation was measured in tests of 3 mm thickness roof. In the tests of 13 mm thickness roof, sloshing impact was measured bigger in comparison with 3 mm thickness roof. The results were discussed in theoretical analysis. Then, torsional sloshing motions were observed and discussed.