Abstract
After forming tie reinforcements into the desired shape, plastic deformation may be induced in the ties because of the cold working. Thus, the ties with residual strain are subjected to tension when a bridge column develops inelastic plastic deformation. Since few investigations have been conducted on the effect of the plastic residual deformation of ties on the lateral confinement of concrete, a series of uniaxial loading test was conducted for circular concrete cylinders confined by ties with the residual plastic strain and those confined by ties in which the residual plastic strain was eliminated by annealing. It was found from the test that the residual strain increases the secant stiffness of concrete between εcc and 2εcc, in which εcc represents the concrete strain at the peak stress.
