Damage to Floating Roof Tank by Sloshing

摘要

(1)Among those tanks of which the natural period coincided with the peak sloshing period as indicated by the seismic ground motion data (velocity response spectrum) in Hokkaido Refinery during the Tokachi-oki Earthquate (a part of 30000Kl and 40000Kl tanks), the calculated sloshing exceeded over 3 meterin height. (2)The height of the sloshing as calculated by the velocity response spectrum method conformed to the actual states. These were verified with the data by using the state of overflowand the actual measurement of the sloshing height, which showed good consistency. (3)The calculated sloshing periods (natural period of the tank sloshing) conformed to the actual state well These were verified with the alarming periods of LA-H units of the FRT and showed good conformity. From the aforementioned facts, the scale of the sloshing (height) can be estimated and evaluated by using the velocity response spectrum method. (4)This study clarified the fact that the pontoon has its own weak partdepending on the type of structure. (5)A.mongthe 100000Kl tank series, the floating roof of tank No. 100651 and No. 100654 submerged even though the height of the sloshing was lower than that of other tanks. From the aforementioned facts, the cause of the failure must to be analyzed by comparing the sloshing simulation result and actual failure situation. In addition, since the damage analysis of floating roof tank carried out FEM analysis, the following news reports it.