Mechanical Properties of High Strength Q460 Structural Steel After Being Exposed to Fire

Abstract

An experimental study was undertaken to investigate the post-fire mechanical properties of high strength Q460 steel. Tensile coupons taken from high strength Q460 steel sheets were exposed to different elevated temperatures up to 900℃, and were then allowed to cool down to ambient temperature before they were tested to failure. Two cooling methods were considered, namely natural cooling and water cooling. Tensile tests were conducted to obtain their post-fire stress-strain curves and associated mechanical properties (yield strength, elastic modulus, ultimate strength and elongation). It was found that the post-fire mechanical properties of high strength Q460 steel are significantly reduced below the original ambient temperature mechanical properties when they are exposed to temperatures exceeding 600℃.