Behavior of high-strength concrete columns with concrete strengths of up to
90 MPa was investigated experimentally. Large-scale columns were tested un
der different levels of constant axial compression and incrementally increa
sing lateral deformation reversals. The columns had a circular cross sectio
n and circular transverse reinforcement. Different volumetric ratios and gr
ades of steel were used to confine the core concrete. The results indicate
that the deformability of high-strength concrete columns can be improved si
gnificantly through confinement. Inelastic drift capacity of columns can be
improved to levels well beyond those usually expected during strong earthq
uakes. The improvements can be achieved with volumetric ratios of confineme
nt steel that are typically used for normal-strength concrete columns, prov
ided that higher grades of steel are used. Furthermore, analytical techniqu
es commonly employed for analysis of normal-strength concrete columns can a
lso be used for high-strength concrete columns, if proper material models a
re incorporated, reflecting stress-strain characteristics of high-strength
concrete and reinforcing steel.