1.重庆大学 土木工程学院，重庆 400045;2.重庆大学 山地城镇建设与新技术教育部重点实验室，重庆 400045
王卫永（1982—），男，河南太康人，重庆大学教授，博士生导师，博士. E-mail：wywang@cqu.edu.cn
TU392.4
中央高校基本科研业务费专项资金资助项目（2019CDQYTM027）
1.School of Civil Engineering， Chongqing University， Chongqing 400045， China;2.Key Laboratory of New Technology for Construction of Cities in Mountain Area (Ministry of Education)， Chongqing University， Chongqing 400045， China
为了研究高强Q960钢在火灾后的力学性能，对过火温度为300~900 ℃的高强Q960钢试件进行了稳态拉伸试验，得到其在自然冷却和浸水冷却条件下的应力-应变曲线、弹性模量、屈服强度和极限强度.结果表明：600 ℃是高强Q960钢强度发生明显变化的临界温度，将试验结果与普通Q235钢、Q345钢和高强Q460钢、Q690钢、S960钢进行比较，发现不同种类钢材经历高温后的力学性能退化程度并不相同；根据试验结果，建立了高强Q960钢高温后力学性能折减系数随温度变化的拟合公式，拟合结果与试验结果吻合较好.
In order to study the post-fire mechanical properties of high strength Q960 steel， the steady state tensile test on high strength Q960 steel specimens after exposure to 300-900 ℃ was carried out. The stress-strain curves， elastic modulus， yield strength and ultimate strength were determind after air cooling and water cooling. The results show that 600 ℃ is the critical temperature of strength loss of high strength Q960 steel. The test results are compared with properties of ordinary Q235， Q345 steels and high strength Q460， Q690， S960 steels. The comparison shows that the degradation degree of mechanical properties after exposure to high temperature varies among different steels. Based on the test results， new fitting equations for evaluating the post-fire mechanical property reduction factors of high strength Q960 steel are proposed. The fitting results are in good agreement with the experimental results.
王卫永,张艳红,李翔.高强
