By analyzing the results of several typical projects' hydrofracturing in-situ stress measurements near the engineering fault structure field, the relativity between the in-situ stress and tectonics' space distribution, motive mechanism and lithology is obtained. The in-situ stress' magnitude general decreases or increases in the tectonics' depth direction and the orientations of maximum horizontal principal stress is almost parallel or vertical to the faults' trend influenced by the motive mechanism. It is helpful to evaluate the stability of engineering rockmass scientifically and to provide the base of project location by analyzing the distribution of geo-stress near the fault structure field.
Geo-stress measurement in the engineering construction, especially in large-scale projects, is more and more important, because it is mainly not only an important factor of regional stability determination, but also the force of deformation and failure during underground or surface geotechnical engineering excavation. Geo-stress measurement is the premise for the determination of engineering rock mechanics, the analysis of surrounding rock stability, the scientific design and decision of geotechnical excavation. With the continuously promoting of China's western development, a large number of high-altitude, super-depth, high temperature differential large-scale underground engineering will be carried out, The influence of geostresses on the projects' stability increases more and more, such as rock burst, gas outburst, surrounding rock's large deformation, the roof falling, the floor water invasion etc. a series of geological disasters related to the geo-stress. Therefore,the measurement and study of geo-stress distribution in the engineering area become one of the mostly conserning issues for scientific and engineering researchers. Geo-stress is the combined result of rockmass's dead weight and tectonic movements. Therefore, how to explore the distribution of stress for the better service of the project construction becomes an urgent problem to be resolved.
