Research on quantitative identification of infrared characteristics of progressive failure of bolted roadway surrounding rock

By means of uniaxial loading and thermal infrared imaging technology, this paper makes physical model test on progressive failure of bolted roadway surrounding rock. The results indicate that: (I) before stress peak, the infrared radiation temperature (IRT) on surface of roadway surrounding rock rise non-synchronously, and the IRT on stress concentration and shear fracture areas is higher and intensive than that on stress relaxation and tensile fracture areas; (II) the IRT on various parts of model such as roof, walls, floor and angles, changes nonsynchronously, which can be reflected through the change rate of IRT to identify the progressive failure of roadway surrounding rock; (Ⅲ) two kinds of infrared precursors can be obtained corresponding to the progressive failure areas of roadway surrounding rock respectively. The bolted areas are determined from the change ratios of TIR temperature of the various areas of the bolted surrounding rocks, which provides a theoretical basis for designing parameter of bolt supporting. It is also verified that the thermal infrared imaging technology can be used to study the mechanism of bolt supporting and supervise the stability of roadway surrounding rock.