Seismic behavior of reinforced concrete walls at elevated temperature

The effect of elevated temperature on the mechanical behavior of concrete and the seismic behavior of reinforced concrete walls was investigated through materials and component testing. Tests were performed on concrete cylinders at temperatures between 70 and 600°F (21 and 316°C). The planar walls had web reinforcement ratios of 0.93% and 2.0%; the concrete compressive strength was approximately 6 ksi (41 MPa) for all walls. The maximum surface temperature for the tests of the walls was 450°F (232°C). Fully reversed, in-plane, inelastic cyclic loading was imposed on the walls in heated and ambient conditions to establish the effects of elevated temperature on peak strength and elastic stiffness. For temperature between 68 and 450°F (20 and 232°C), the materials tests showed a reduction in concrete uniaxial compressive strength and compression modulus of elasticity of no more than 10% and 30%, respectively. The wall tests showed no meaningful effect of temperature on either peak strength or secant stiffness to peak strength in both heated (up to 450°F [232°C]) and residual (tested at room temperature after cooling from 450°F [232°C]) conditions.