Employing Internal Flexible Wall as Mass Absorber in Tanks Subjected to Harmonic Excitations

The possibility of employing internal wall as mass absorber in rectangular water storage tanks subjected to harmonic ground motion excitation is investigated in this paper. Internal walls are used in these tanks usually for service performance purposes, which could be used as mass absorber to control seismic demand on tank's exterior walls. Derivation of the response of the coupled system including rigid external walls, flexible internal wall and fluid field is in frequency domain. The responses of the tank are evaluated subjected to harmonic excitations. By tuning the dynamic behavior of the tank and the sloshing liquid by changing the mass and stiffness of internal flexible wall, it is shown that wave elevation and water pressure on external rigid walls can be significantly reduced.