The Effect of ReservoirFilling, on the Modification Factor of SteelElevated Water Tanks, Considering Fluid-Structure Interaction

In order to investigate the effect of fluidstructure interaction on the modification factor of steel elevated watertanks with braced columns, three real models having capacity of 134, 160 and 82 m3are selected. Each model is considered to be empty, 25%, 50%,75% and 100% full and is designed according to 4thversion of Iranian2800 seismic code, taking into account Sa=0.25g & Sa=0.35g spectral accelerations, for soil types 1,2,3 &4. On each model, the information of Convective mass, Impulsive mass and the spring stiffness of the convective mass, is added according to Housner’s method. Later all designed models are subjected to 10 accelerograms, recorded on each soil type and scaled to Sa=0.25g & Sa=0.35g. Total 960 linear and nonlinear timehistory analyses are carried out on finite element models. Finally, after applying Modal Pushover analysis on each model, modification factors for various types of filling the reservoir is calculated and results achievedare discussed

Keywords:

Time History Analysis , Fluid-Structure Interaction , Steel Elevated WaterTanks , Static Nonlinear nalysis