Analytical Comparison Of The Ordinary And High Strength Steel Reinforced Concrete Frames Against Earthquakes

Abstract

Failure mechanisms in ordinary RC frames can be prevented by adopting strong
column weak beam philosophy. Limited flexural strength and lateral deformation capacity of the RC
columns often results in the formation of failure mechanisms. Large inelasticity at the column base
can be prevented by providing high strength reinforcements in columns. Two bays three story frames
reinforced with high strength and ordinary reinforcements in columns are modeled on MSC.MARC
finite element code. For section behavior fiber model THUFIBER is used. Bond failures between steel
and concrete and slip at the column base are ignored. Modeled frames are also tested. Simulated and
the test results are compared. Test results on two bays three story frames with high strength
reinforcement in columns and ordinary reinforcements in beams reveals more stable response at large
lateral displacements. With the simple replacement of ordinary steel in the column of RC frames,
passive frame mechanism can be achieved. Difference between analytical and test results can be
realized by recognizing the basic assumptions behind the formulation of fiber model. Nevertheless, the
observed and modeled behavior has been found in good agreement