结构钢材全过程真实应力-应变关系研究  

STUDY ON THE WHOLE PROCESS TRUE STRESS-STRAIN RELATIONSHIP OF STRUCTURAL STEELS

作　　者：魏陆原 杨飞 延睿 段留省[1] WEI Lu-yuan;YANG Fei;YAN Rui;DUAN Liu-sheng(School of Civil Engineering,Chang’an University,Xi’an,Shaanxi 710061,China;Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hong Kong 999077,China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061 [2]香港理工大学土木及环境工程学系,中国香港999077

出　　处：《工程力学》2025年第4期216-225,272,共11页Engineering Mechanics

基　　金：国家自然科学基金项目(52208144);陕西省自然科学基金项目(2022JM-214);长安大学中央高校基本科研业务费专项资金项目(300102282102)。

摘　　要：对钢结构的连接部位或节点域进行大变形或断裂模拟分析时,需准确考虑钢材的全过程真实应力-应变关系。对Q355和Q420钢材开展单轴拉伸试验获得其全过程工程应力-应变曲线,采用有限元方法对两种钢材的拉伸试验进行模拟,通过比较有限元分析和实测工程应力-应变曲线的吻合度,对描述钢材颈缩后真实应力-应变曲线的Ling方法、Swift+Voce方法、以及该文提出的改进Ramberg-Osgood方法的适用性和准确性进行评价。为进一步探讨三种方法对描述高强钢真实应力-应变关系的适用性,对相关文献报道的S690和S960钢材拉伸试验也进行了模拟分析。结果表明:Ling方法、Swift+Voce方法、以及该文提出的改进Ramberg-Osgood方法均能较准确地描述Q355和Q420的真实应力-应变关系,也适用于描述S690和S960两种高强钢的真实应力-应变关系,验证了三种方法对描述包括高强钢在内的结构钢材真实应力-应变关系的普适性。The whole process true stress-strain relationship of steel material should be accurately considered when simulating the large deformation or fracture of the connecting parts or joint domains in steel structures.Firstly,uniaxial tensile tests on Q355 and Q420 steels were carried out to obtain the whole process engineering stress-strain curves.The finite element method was used to simulate the tensile tests of the steels.Through comparing the consistency between the finite element analysis and the measured engineering stress-strain curves,evaluated were the applicability and accuracy of Ling method,of Swift+Voce method,and of the improved Ramberg-Osgood method proposed for describing the post-necking true stress-strain curve of steels.To further explore the applicability of the three methods of describing the true stress-strain relationship for high-strength steels,the tensile tests on S690 and S960 steels reported in literature were simulated and analyzed.The results show that Ling method,Swift+Voce method,and the improved Ramberg-Osgood method proposed can accurately describe the whole process true stress-strain relationship of Q355 and Q420.Besides,these methods can also be used to describe the whole process true stress-strain relationship of S690 and S960.The universality of the three methods for describing the true stress-strain relationship of structural steels including high-strength steels is verified.

关 键 词：钢结构 真实应力-应变关系 有限元分析 结构钢材 拉伸试验 Ramberg-Osgood 

分 类 号：TU511.3[建筑科学—建筑技术科学]