摘要
把光学应变测量系统(ARAMIS 3D)用于研究生的高等实验力学实验中,开发了多个研究型实验。论文介绍了一个典型实验,利用数字图像相关方法(Digital Image Correlation,DIC)测定了带孔铝合金圆试件的拉伸弹性模量,观测圆孔周围的应力集中现象。在分级载荷下,采集试件变形前后的数字图像,对所采集的一系列数字图像进行相关计算获得三维应变场分布规律,从而获得拉伸铝试件的弹性模量。并将实验结果与电测法测得的弹性模量进行比较,两者吻合良好。同时,通过应变云图我们非常直观地观察到试件圆孔附近的应力集中现象。实验结果表明,利用这种简单高效的方法测定各种试件的弹性模量是可行的,具有很好的应用价值。更重要的是,能为一些利用传统接触式测量技术难以测量的试件提供一个新的研究途径。该光学应变测量系统可以非接触式的准确直观地实现对位移场、应变场的三维测量,能够更好地满足工程实验测试的要求。把该系统引入研究生的高等实验力学实验中,可进一步培养学生的科研意识、创新精神,更好地开拓学生的新视野,加深对力学知识的理解和掌握,极大地提高学生的科研积极性,更好地了解和掌握当前力学领域的先进测量手段,为做科研打下坚实的基础。
Optical strain measurement system based on three-dimension digital image correlation （3D-DIC） has been employed for postgraduate experiment teaching in the advanced experiment mechanics, and several research-oriented experiments have been designed and developed. This paper presents a typical experiment. The tensile elastic modulus of aluminum cylindrical specimens with through-hole was measured and the hole-edge strain concentration was observed directly. Furthermore, the elastic modulus of aluminum specimens performed by the proposed 3D-DIC system was carefully compared with this obtained by strain gage. The agreement between the two measurements was good. The experimental results demonstrated that the optical technique used for the measurement of elastic modulus of various material specimens was simple yet effective, hence, the high accuracy of 3D-DIC system was verified. More importantly, the optical technique provided a new study routine for the strain and displacement measurement of the specimens that cannot be measured by conventional contact methods. This high-accuracy 3D-DIC system can accomplish the three-dimension displacement and strain field contactlessly and visually. It was used in postgraduate experiment teaching. The result showed that the experiment can further enhance the capacity for scientific research and innovation and broaden the horizon of the students. And it makes postgraduates deeply understand and master the knowledge of mechanics and advanced measurement methods in the field of mechanics.
出处
《实验室研究与探索》
CAS
北大核心
2015年第3期220-222,254,共4页
Research and Exploration In Laboratory
基金
国家自然科学基金青年科学基金资助项目(51202122)
关键词
光学应变测量系统
数字图像相关
研究型实验
研究生实验教学
Key words： optical strain measurement system
digital image correlation
research-oriented experiments
postgraduateexperiment teaching
