The Experimental Study Of Rock Stick-slip Dynamic Process

The stick-slip experimental of rock structure is used to reappear earthquake approximatively. The changes of mechanical quantity are observed in this experimental in order to understanding the premonitory characters and formation mechanism of earthquake. But there are some problems in the stick-slip experimental study at present; for example, the details of slide and buckling failure are confused. The formation mechanism and regularity of stick-slip could not only summarize deeply due to these problems, and also some meaningful work could not be developed for earthquake study as well.A high-speed image measurement system was built insure time resolution and spatial resolution of the image with two high-speed cameras. Because there is a start time difference between two high-speed cameras in this measurement system, image sequences could not be aligned in time. In order to solve the problem of the time difference, the magnitude and distribution of start time difference between two high-speed cameras were studied systematically. The correction method is developed about the start time difference.A damage evolution analytical method based on the statistic of the strain field and a positioning method of high-speed crack which based on statistic of the displacement field are both developed in this research. These post-processing analysis methods are not only increasing the measurement resolution further, but also providing some methods to analyze the damage evolution and the crack propagation law in dynamic destabilization process of stick slip quantificationally.The deformation characteristics of rock stick-slip are analyzed through experiments, by utilizing the designed high-speed image measuring system and statistical method. Discusse the evolution of damage through the statistical analysis of whole damage factors in the process of stick-slip. It is found that stick-slip instability began from a little point to pass the whole interface quickly unstable the dislocation unstable dynamic process. Rule of the dislocation is summarized by comparative analyzing different groups of stick-slip experiments.A model which embodies the microstructure of interface is used to study the dynamic process of rock stick-slip. Determine the main parameters of model, through the data of experiment. The reason about the instability of the fault was found that sliding is caused by spreading destruction of concave and convex body in the local, through the results of numerical calculation. Waves are generated by spreading about the damage, corresponding to the wave is sliding in sequence along the fault.This research summarizes the rules of the damage evolution and crack propagation quantitatively by the analysis of experiment and numerical simulation on rock stick-slip. The instability process of the rock stick-slip is understood furtherly, and some exploration work is useful in research genesis process and mechanism of earthquake.