(上海交通大学土木工程系，上海 200240 )

［摘要］采用MTS材料试验机和分离式霍普金森压杆(SHPB)装置，对我国钢结构建筑中常用的Q345钢进行准静态压缩试验和不同应变率下的冲击性能试验。试验结果表明：Q345钢在动态冲击下的强度明显高于准静态压缩下的强度，具有显著的应变率强化效应；但在分别比较准静态和动态冲击各自区域的应力水平时，发现不同应变率下其值相差不大，表现出对应变率变化不敏感的性质。在试验基础上，拟合得到了可用于冲击荷载作用下进行结构分析的材料本构模型。

［关键词］Q345钢；SHPB试验；应变率效应；本构模型

中图分类号：TU391文献标识码：A文章编号：1002-848X(2011)03-0028-03

Research of dynamic mechanical behavior of Q345 steel

Yu Wenjing, Shi Jianyong, Zhao Jincheng

(Department of Civil Engineering, Shanghai Jiaotong University, Shanghai 200240, China)

Abstract:Applying the MTS material testing machine and  Split-Hopkinson Pressure Bar (SHPB) testing technique, the quasistatic compression and impact experiment under different stain rates of the Q345 steel which is widely used in steel structures were carried out. The experimental results show that  the dynamic strength of the Q345 steel is obviously higher than that under the quasi-static state. It displays an obvious stain rate strengthening effect. The stress levels of the Q345 steel under different strain rates respectively in quasi-static and dynamic region  are so close to each other that it can be taken for a non-sensitive material. Based on the experimental data, a constitutive model used for structure analysis under impact load was determined.

Keywords:Q345 steel; SHPB test; strainrate effect; constitutive model

*中国高技术研究发展“863”计划资助项目（2007AA09Z322）。

作者简介：于文静，博士研究生，Email：wjfish@sjtu.edu.cn。

参考文献

［1］李国强，陈凯，蒋首超，等.高温下Q345钢的材料性能试验研究［J］. 建筑结构，2001，31（1）：53-55.

［2］屈立军，李焕群，王跃琴，等.国产钢结构用Q345（16Mn）钢高温力学性能的恒温加载试验研究［J］土木工程学报，2008，41（7）：33-40.

［3］屈立军，李焕群，王跃琴，等. 国产钢结构用Q345（16Mn）钢在恒载升温条件下的应变温度应力材料模型［J］.土木工程学报，2008，41（7）：41-47.

［4］JOHSON G R，COOK W H．A constitutive mode and data for metals subjected to large strains，high strain rate and high temperatures［C］//Proceedings of the Seventh International Symposium on Ballistics．Netherlands：The Hague，1983：541-547.

［5］孙建运，李国强. 动力荷载作用下固体材料本构模型研究的进展［J］.四川建筑科学研究，2006，32（5）：144-149.

［6］刘旭红，黄西成，陈玉泽，等. 强动载荷下金属材料塑性变形本构模型评述［J］. 力学进展，2007，37（3）：361-374.

［7］SASSO M，NEWAZ G，AMODIO D.Material characterization at high strain rate by Hopkinson bar tests and finite element optimization［J］. Materials Science and Engineering A, 2008(487) : 289-300.

［8］LEE WOEI SHYAN，LIU CHENYANG. The effects of temperature and strain rate on the dynamic flow behaviour of different steels［J］. Materials Science and Engineering A, 2006 (426) : 101-113.

［9］WULF G L．The high strain rate compression of 1023 and 4130 steels［J］．International Journal of Mechanical Sciences，1978，20(12)：843-848.

［10］NEMATNASSER S. Thermomechanical response of DH36 structural steel over a wide range of strain rates and temperatures［J］．Mechanics of Materials，2003(35)： 1023-1047.

［11］RAJEEV KAPOOR, SIA NEMAT\|NASSER. Determination of temperature rise during high strain rate deformation［J］．Mechanics of Materials, 1998 (27) : 1-12.

［12］尚兵，盛精，王宝珍，等.不锈钢材料的动态力学性能及本构模型［J］. 爆炸与冲击，2008，28（6）：527-531.