岩石变形破坏的数字散斑相关方法研究

 采用白光数字散斑相关方法作为实验的观察手段，对单轴压缩条件下岩石变形破坏进行实验研究。根据实验中数据采集方式的不同要求，将实验分成2组进行：一组是通过CCD相机记录岩石加载全程的试件表面散斑图像，进行岩石加载全程的变形演化实验研究，根据计算结果对岩石加载全程的变形演化和变形集中区域的位移演化进行研究；另一组是通过高速相机记录岩石破坏瞬态过程的试件表面散斑图像，进行岩石破坏瞬态过程的变形演化实验研究，采用不同时刻的散斑图像作为参考帧，分别进行塑性硬化到峰值阶段变形场演化特征、峰值到破坏阶段变形场演化特征的分析。同时，实验研究中还得到试件加载过程中局部化带内变形量值、带内变形最大值与最小值之比，带内最大值与带外平均值之比，以及试件表面裂纹扩展的平均速度等定量参数。

EXPERIMENTAL INVESTIGATION ON FAILURE OF ROCK BY DIGITAL SPECKLE CORRELATION METHODS

The experiments of the deformation and failure of rock under the condition of uniaxial compression were carried out by using the white digital speckle correlation methods. According to the experimental data collected in different ways，the experiments were divided into two groups. A group of experiment investigated the deformation evolution process of rock loaded，the specimen surface speckles images were recorded by CCD camera，According to the calculation results，the rock deformation evolution was studied. The other group of experiment investigated the deformation evolution process of the transient of rock damage；the specimen surface speckles images were recorded by adopting high speed cameras. By adopting the different times speckle images as reference frame，the plastic hardening to peak stage deformation evolution characteristics and the peak to destroy phase analysis of deformation evolution characteristics were carried out. At the same time，some quantitative parameters were obtained in the experiments，such as the value of deformation，the ratio of maximum and minimum values of the deformation in the deformation localization band，the ratio of deformation values inside and outside the deformation localization band，and the average speed of crack propagation.