On the Coupling Relationship between Strain Field and IRR Temperature Field of Rock

摘要

The tectonic activity and rock fracturing will cause changes of strain and infrared radiation (IRR). Theoretically there exist certain relationships between strain and IRR in that they both are the results of stress activity of the crust. To obtain the relationships is the key to monitor tectonic activity and rock hazards, including geological hazards, earthquake and mine hazards and so on, by use of remote sensing technology. In this paper two kinds of physical simulation experiments on IRR imaging detection and strain measure were carried out to reveal the relationships between strain field and IRR temperature field. In one of the experiments a disconnected-fault sample was used to simulate the activity of geological tectonic, while in another a hole-bored rock sample was used to simulate the fracturing process of rock tunnels. An infrared thermal imager was used to detect the changes of IRR, and a digital camera was used to monitor the visual light image. In order to obtain the strain fields of the loaded samples, the digital speckle correlation method (DSCM) was applied. The experimental results showed that there are nice relationships between IRR temperature field and strain field. The IRR temperature increased in the position of compressing strain, while decreased in the position of tensile strain. With the spatial transferring of strain concentration the high IRR temperature spot transferred correspondingly. As the loaded samples get failure, some large strain strips appeared along the fracturing positions. If the fracturing is shear-resulted the IRR temperature of the strip increased, and if the fracturing is tensile-resulted the IRR temperature of the strip hardly changed. The results in this paper are meaningful for the remote sensing and early warning of rock fracturing, tectonic activity and earthquake.