Study on the breaking process of jointed rock mass by disc cutters based on digital image correlation and infrared thermography

Jointed rock masses are frequently encountered during the TBM excavation. To investigate breakage mechanism of jointed mass by disc cutter and precursory information before failure, a series indentation tests were performed on shear rheological test system. During test, breaking process specimens recorded digital image correlation system thermal infrared imager simultaneously. Therefore, strain fields images cutters obtain. The experimental results show that failure can be divided into four stages: compaction stage, linear elastic residual transition stage post-failure stage. Besides, characteristic shows good accordance with radiation temperature at each samples is dominated localized rise an important precursor fracture instability. great significance to deep understanding warnings engineering disasters.