建筑结构学报2025，Vol.46Issue(6)：96-106,11.DOI:10.14006/j.jzjgxb.2024.0262
Q355、Q460和Q690钢材高温力学性能对比研究
Comparative study on high-temperature mechanical properties of Q355,Q460 and Q690 steels
摘要
Abstract
At present,the existing studies on the high-temperature mechanical properties of steels with strengths of 355 MPa,460 MPa and 690 MPa have large dispersion in the research results,making it difficult to accurately reflect the differences in high-temperature mechanical properties between these three types of steels.This paper conducted comparative experimental research on Q355,Q460 and Q690 steels under consistent test conditions,and compared the experimental results with current mainstream structural fire resistance design standards and published data.The test results show that the difference in mechanical properties of Q355,Q460 and Q690 steels under consistent test conditions is notably smaller than the difference in test data in existing literature.Overall,the yield strength reduction factor for Q355 steel is lower than that of the two high-strength steels.The increase in ultimate strength due to blue-brittleness phenomenon is more pronounced in Q460 steel compared with the other two steels;at 800℃,Q460 steel demonstrates better ductility than the other two steels.With regards to elastic modulus,the EC3 and AISC specifications are generally conservative,while the GB 51249-2017 specification is not safe for Q355 steel and more conservative for Q460 and Q690 steels.For yield strength,the AISC,BS 5950 and EC3 specifications align well with the experimental result,while the GB 51249-2017,AS 4100 and BS 5950 specifications are not safe for Q355 steel and more conservative for Q460 and Q690 steels.The AISC specification's recommended limit strength becomes not safe after 400℃.关键词
结构钢/高温/受火试验/力学性能/折减系数Key words
structural steel/elevated temperature/fire test/mechanical property/reduction factor分类
土木建筑引用本文复制引用
蒋彬辉,刘彤,王梦洁,屈怡秋..Q355、Q460和Q690钢材高温力学性能对比研究[J].建筑结构学报,2025,46(6):96-106,11.基金项目
国家自然科学基金项目(52378547,51908560). （52378547,51908560）
