弯曲荷载诱发微型梁开裂演化过程的可视分析

深圳大学土木工程学院,广东省滨海土木工程耐久性重点实验室,深圳市土木工程耐久性重点实验室,广东深圳 518060

结构工程; 三点弯曲; 裂缝扩展过程; 裂缝长度; 三维可视化; X射线微观层析成像

Visual analysis for cracking evolution of micro-beam under three-point bending
TENG Xiaojuan, LIU Yuqing, LIU Peng, HONG Shuxian, DONG Biqin, and XING Feng

College of Civil Engineering, Key Laboratory of Durability for Marine Civil Engineering of Guangdong Province, Shenzhen Key Laboratory on Durability of Civil Engineering, Shenzhen University, Shenzhen 518060, Guangdong Province, P.R.China

structural engineering; three-point bending; crack propagation process; crack length; 3D visualization; X-ray microcomputed tomography

DOI: 10.3724/SP.J.1249.2018.05460

备注

传统的三点弯曲试验无法对试样内部裂缝进行可视量化分析.为了直观地观察三点弯曲下试样开裂演化过程,采用X射线微观层析成像(X-ray microcomputed tomography,X-ray μCT)技术对三点弯曲荷载作用下微型梁的开裂过程进行原位追踪监测,基于试样的二维/三维的形貌特征图对孔隙和裂缝进行可视量化分析.结果表明,X-ray μCT测试技术是一种有效的非破坏性的原位跟踪方法,可以获得试样内部孔隙与裂缝三维可视化图,获取三点弯曲试验的试样裂缝扩展全过程,并可进一步对试样的裂缝与孔隙进行定量分析,获得X-ray μCT测试裂缝长度变化曲线与裂缝体积柱状图.研究表明,裂缝长度与体积随加载呈上升趋势.

The traditional three-point bending test is unable to realize visual quantitative analysis of sample internal crack. In order to observe the crack evolution process, we, in-situ, track and monitor the micro-beam cracking process under the three-point bending by X-ray microcomputed tomography technology(X-ray μCT). We analyze quantitatively the pore and crack of micro-beam by 2D/3D visualization of the morpholog characteristics. The results show that X-ray μCT technology test is an effective nondestructive and in-situ tracking method; The three-dimensional visualization of pore and crack and the crack propagation under three-point bending test can be obtained; moreover, crack and pore quantitative analysis can be performed to get the length variation curve of crack under X-ray μCT test and the crack volume histogram.

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