Inversion of Initial Geo-Stress in High and Steep Slope

Abstract

At present, due to various reasons, cannot do a large number of field measurements, and the measured results often can only reflect the local stress field distribution. What’s more, the measured results has discreteness, it’s difficult to describe the law of the initial stress field distribution in the entire region. This paper combines topographic and geological conditions and the measured in-situ stress value of Jinping I hydropower station dam area, using FLAC3D4.0, select geological section profile of II1 exploration line for reference, to simulate the incised process of the valley. We get the stress field distribution when rock gravity acting alone, and exert horizontal tectonic stress based on the calculate result of gravity field in the VI terrace model. We inversion the distribution of current Valley stress field, and validate the rationality of the design after compare with the measured data. We obtain the features of stress field of current valley. And we also proved that the regional principal compressive stress plays a decisive role in the formation of the current valley stress field.

Inversion Method of Initial In Situ Stress Field Based on BP Neural Network and Applying Loads to Unit Body

“…Field measurements of in situ stress are the most direct methods to provide regional in situ stress field; the commonly used methods include overcoring, strain-relief, inverse solving methods, hydraulic fracturing test, borehole breakouts, acoustic emission, fault plane solution, differential strain analysis, and observation of discontinuity states [26][27][28]. However, due to the influence of factors such as site, funding, and testing technology, especially in the difficult and dangerous areas of southwest China, not only is the geological structure complicated, but also the terrain conditions on the ground are difficult, making it hard to conduct numerous and comprehensive measurements [29][30][31]. In addition, the measured in situ stress data reflects the characteristics of the local stress field to a large extent [32,33].…”