高温后Q235钢材浸水冷却后的残余力学性能试验研究  

Experimental study on residual mechanical properties of Q235 steel after water cooling from elevated temperatures

作　　者：曾杰 张春涛[1] 张誉[1] ZENG Jie;ZHANG Chuntao;ZHANG Yu(College of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyan 621010,China)

机构地区：[1]西南科技大学土木工程与建筑学院,绵阳621010

出　　处：《建筑结构》2024年第12期43-49,共7页Building Structure

摘　　要：对高温后Q235钢浸水冷却后的力学性能进行了试验研究。首先将试件分别加热到500、600、700、900℃以模拟不同温度的火灾,再将高温试件浸水冷却至常温,然后对试件进行拉伸试验,观察浸水冷却条件下Q235钢材的拉伸断裂特征,并获得其应力-应变关系曲线及主要残余力学性能参数。通过试验结果分析讨论了浸水冷却条件下,火灾温度对Q235钢材力学性能的影响规律。同时,基于已有研究成果,对高温后浸水冷却条件下Q235、Q345和Q355三种强度等级接近钢材的残余力学性能受火灾温度的影响情况进行了对比分析。最后,结合试验研究结果,建议了Q235钢在20~900℃浸水冷却后屈服强度、抗拉强度等力学性能参数随火灾温度变化的预测方程,为采用水灭火后Q235钢材的残余力学性能评估提供帮助。The mechanical properties of Q235 steel after water cooling from elevated temperatures were experimentally investigated.Firstly,the specimens were heated to 500,600,700 and 900℃respectively to simulate fires at different temperatures and then the elevated temperatures specimens were immersed in water and cooled to normal temperature.Then the tensile tests were conducted on the specimens to observe the tensile fracture characteristics of Q235 steel under water cooling condition,and the stress-strain relationship curve and the main residual mechanical properties parameters were obtained.The effect of fire temperature on mechanical properties of Q235 steel under water cooling condition was discussed through analysis of experimental results.At the same time,based on the existing research results,the effects of fire temperature on the residual mechanical properties of Q235,Q345 and Q355 steels with similar strength grades after water cooling from elevated temperatures were compared and analyzed.Finally,combined with the experimental results,the prediction equations of the yield strength,tensile strength and other mechanical properties of Q235 steel after water cooling at 20~900℃with the change of fire temperature were proposed,which can be helpful for the evaluation of residual mechanical properties of Q235 steel after extinguishing with water.

关 键 词：Q235钢材 高温 浸水冷却 残余力学性能 预测方程 

分 类 号：TU398.7[建筑科学—结构工程] TU511.3