Abstract
Non-linear time-history analyses on single-degree-of-freedom systems with load-displacement relations of prestressed and conventional reinforced concrete members are reported. The analytical results are used for investigating response characteristics of prestressed concrete systems and deriving substitute damping. The energy time-history of prestressed concrete systems is compared with that of reinforced concrete. The substitute damping obtained is compared with equivalent viscous damping derived directly from the load-displacement relationship of the systems. Referring to the substitute damping from the dynamic response analyses and the equivalent viscous damping from the stationary load-displacement curves, equivalent structural damping for concrete structures to be used in the capacity spectrum method is proposed.
