基于图像分析的土坡离心模型试验变形场测量

Displacement measurement using image analysis in centrifuge modeling of slopes

摘要: 开发了离心场条件下土坡离心模型试验变形场非接触测量技术并进行了实际应用。基于图像相关分析理论,开发了新的土坡离心模型试验过程中土体位移非接触测量系统以观测离心机运行中土坡的位移。针对简单土坡进行了离心模型试验,测量了土坡的位移场变化过程。测量结果规律性好,表明该非接触测量技术能够较好地测定离心模型试验中土体侧面任意点在任意时刻的位移,适用于离心场环境中土坡变形过程的测量。加载导致土坡在某些位置出现变形集中,意味着这些位置发生了应变局部化。应变局部化的发展与土坡破坏有着密切联系。

Abstract: A new displacement measuring system was presented and applied in centrifuge model tests on soil slopes.The non-contact measuring system was developed based on the correlation-based image analysis to measure the displacements of a soil slope in centrifuge tests.The histories of displacement fields of soil slopes in centrifuge were automatically measured.The measured results exhibited a good regularity.The measuring system was verified to effectively measure the displacement at any spot of a slope at any time with accuracy in centrifuge.It was shown that the deformation was concentrated due to loading,which demonstrated the occurrences of strain localization in the slope.The strain localization had a close relation with the failure process.