Simulated Seismic Load Tests on Reinforced Concrete Columns

Abstract

Simulated seismic load tests conducted on 11 reinforced concrete columns are described. The columns had a 400‐mm (15.7‐in.) square or octagonal cross section and contained various quantities of transverse reinforcement. The columns were subjected to either low, moderate, or high axial compressive loads and to reversible quasi‐state lateral loads that simulated severe earthquake loading. The tests were conducted to check an analytical approach for the determination of the available flexural ductility and the enhancement of flexural strength of columns with various levels of transverse confining reinforcement. The analytical approach for determining the quantities of transverse reinforcement required for confinement is shown to be conservative and to lead to equations more suitable for the design of transverse reinforcement for confinement than current code equations. Conclusions are also reached concerning the required length of the confined region in the potential plastic‐hinge zones of reinforced concrete columns.