Q345与Q460结构钢材单调和循环加载性能比较  

COMPARISON OF MONOTONIC AND CYCLIC PERFORMANCES OF STRUCTURAL STEEL Q345 AND Q460

作　　者：戴国欣[1,2] 王飞[1,2] 施刚[3] 王元清[3] 石永久[3] 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]山地城镇建设与新技术教育部重点实验室(重庆大学),重庆400045 [3]土木工程安全与耐久教育部重点实验室,清华大学土木工程系,北京100084

出　　处：《工业建筑》2012年第1期13-17,55,共6页Industrial Construction

基　　金：国家自然科学基金重点项目(51038006)

摘　　要：因循环硬化、软化和包辛格效应等的影响,钢材在循环加载下的力学性能与单调加载下的力学性能会有很大差异。借助于对Q345和Q460两种强度等级钢材的单调和循环加载试验,分别从单调加载性能、循环加载现象、循环加载力学性能以及循环本构模拟等几个方面分析它们力学性能差异。分析结果表明,两种钢材单调加载下的延性都比较好,且Q460钢材的延性要优于Q345的。两种钢材循环加载时应力-应变曲线具有循环硬化、循环软化和包辛格效应等现象;循环作用使得两种钢材的硬化作用提前,Q345钢材的循环硬化现象更明显;Q460钢材循环荷载下的滞回耗能能力并不比Q345钢材差,同时循环荷载下钢材产生累积损伤。混合强化模型能较好地模拟两种钢材的循环拉压曲线,为进一步研究此类钢材结构抗震性能提供较为准确的本构模型。The mechanical properties of steel under monotonic loading and cyclic loading are quite different,because of cyclic hardening,cyclic softening and bauschinger effect.Based on the monotonic and cyclic loading experiment of structural steel Q345 and Q460,the comparison of monotonic performance,cyclic loading phenomenon,cyclic performance and cyclic constitutive model were analyzed.The results showed that：the ductility was good under monotonic loading and Q460 was better.The stress-strain curves possed of the phenomenon of cyclic hardening,cyclic softening,and Bauschinger effect.The hardening was advanced under cyclic loading and Q345 was remarkable.The energy dissipation capacity of Q460 was not lower than Q345,and steel occured cumulative damage under cyclic loading.The mixed hardening model could well simulate the cyclic tension-compression curves,which might provide cyclic constitutive model accurately of Q345 and Q460 to study the seismic behavior of steel structures.

关 键 词：高强度钢材 单调加载 循环加载 延性 滞回性能 

分 类 号：TU511.3[建筑科学—建筑技术科学]