刀具侵入作用下节理岩体位移及应变场演化特征试验研究

为了研究在全断面岩石隧道掘进机(TBM)作用下节理岩体的变形破坏特征,采用DSCM方法,通过对加载过程中试件表面数字散斑图像进行计算分析,获得刀具侵入作用下临界状态不同节理参数(倾角和间距)试件表面的位移场以及应变场分布特征。研究结果表明:节理参数的不同对试件表面位移场和应变场分布有着明显的影响,节理的空间位置控制着试件表面变形局部化特征,进而影响裂纹的扩展模式。试件达到临界破坏状态时,其应变场的分布特征能够很好地反映损伤局部化的特点。

EXPERIMENTAL STUDY ON THE DISPLACEMENT AND STRAIN FIELD OF JOINTED ROCK MASS UNDER WEDGE INDENTATION

The DSCM method was adopted for studying the deformation failure characteristics of the jointed rock mass under the whole-sectioned rock TBM. The digital speckle images on the sample surfaces were computed and analyzed. Then the distributions of the displacement and strain field were obtained on the sample surfaces under the critical state with different jointed parameters (the angle of the joints and the distance between joints) underwent the invasion of the cutter. The results showed that the distributions of the displacement and strain field related to the jointed parameters closely. The deformation localization characteristics on the sample surfaces were controlled by the special position of the joints. Moreover, the extended mode of the cracks on the sample was affected by the special position of the joints. The damage localization features can be reflected well by the distributions of the strain field on the sample surfaces when the critical failure state reached in the rock mass.