Rocking behavior of unanchored flat-bottom cylindrical shell tanks under action of horizontal base excitation

The rocking dynamics of the tank is discussed through introduction of the rock–translation interaction. Firstly, the discussion on the ideal rigid bottom plate tank ensures the necessity of the rock–translation interaction for evaluating rocking responses of the tank. Secondly, to trace rocking behaviors of the actual tank, the proposed method is expanded by employing an assumption of the effective moment inertia of liquid for rocking motion. The comparison of analytical results with the experimental ones corroborates its applicability. Finally, the sufficient friction on the pivoting edge to enter and sustain the rocking motion of the tank is examined.