Evaluation response reduction factor of RC framed staging elevated water tank using static pushover analysis

The basic principal of earthquake resistance design of structures is that the structure should not collapse but damage to the structural elements is permitted. Since a structure is allowed to be damaged in case of severe shaking, the structure should be designed for seismic forces much less than what is expected under strong shaking, if the structures were to remain linearly elastic. Response reduction factor is the factor by which the actual base shear force should be reduced, to obtain the design lateral force. The response reduction factor (R) is depends on Over strength (Rs), Ductility (Rμ), Redundancy (R_R). In the present study efforts are made to evaluate the response reduction factors of RC framed staging elevated water tanks having staging height of 12 m but having varying capacities. The effects of seismic zone and fundamental time period of water tank on the Response reduction factor are also discussed. Displacement controlled nonlinear pushover analysis is used to evaluated the base shear capacity and ductility of tanks. It is observed that value of R for elevated water tank is significantly affected by the seismic zone, time period and capacity of tanks.