Influence of Stiffeners and their arrangement on frequency and seismic response of intake tower during construction

In this study, the effects of added stiffeners on the frequency and seismic response of an intake tower during construction period are investigated. For this purpose and in order to better investigate the effects of stiffeners, two types of circular and vertical stiffeners have been used in different numbers and height levels. It is also examined for situations where the weight of the structure is reduced in the amount of the added stiffeners' weight.In this study, the frequency responseof these models after adding the stiffeners was compared with the original model. The results show that the initial frequency of the structures is reduced and increased by the use of circular and vertical stiffeners, respectively. This indicates the effects of type and number of stiffeners on the frequency response of the structure. In order to better investigate the effects of these types of stiffeners, examined intake towers have been subjected to seismic excitation. The results show that the displacements and stresses are increased for the states in which circular stiffeners are considered. Also, for the intake towers with the vertical stiffeners, the values of displacements are decreased and the stress values are adjusted depending on the level of stiffeners. The results indicate the importance of the effects of stiffeners on the frequency response and seismic response of the intake tower and indicate the necessity of investigating these states.