Current situation of the study on Kaiser effect of rock acoustic emission in in-situ stress measurement

Based on periodical literature, the statistics of papers on accoustic emission since recent twenty years were made. The principle and mechanism of acoustic emission, space positioning for the samples were presented.With the theory of elastic mechanics, six direction and four direction methods in space for in-situ measurement using the rock acoustic emission were derived. There are two sampling methods according to the different methods.Influence factors of acoustic emission in in-situ stress measurement, determining method of Kaiser Point and treatment technique for signal and noise were systematically expounded. Two methods which are different from the traditional in-situ measurement are introduced. Problems and research trend of the in-situ stress measurement using acoustic emission were analyzed.