No abstract

The orthogonal design can make sites in the test range uniformly distributed, which is introduced to slope sensitivity analysis, and can greatly reduce the test times and gets a good test effect.The paper takes the flood discharging tunnel import slope of Jinchuan hydropower station for example, which is a rock slope. This article selects the bulk density, internal friction angle, cohesion, earthquake acceleration four factors to design the orthogonal experiment, and the safety factor of the slope as a test indicators, using the simplified Bishop method of limit equilibrium theory to calculate the safety factor and analyses the slope sensitivity. The results show that the cohesion and earthquake acceleration are the most sensitive factors, and have a very significant impact on the slope stability.

thermal conductivity of soil is a basic physical property related to heat conduction, and also is one of parameters widely applied in geotechnical engineering. The effect of gradation on the thermal conductivity of fused quartz was analyzed by thermal needle tests. The different particle size with the same uniformity coefficient (C u = 3.2) and different uniformity coefficient for the same particle size (0.10~1.00 mm) were considered in this study. It shows that the thermal conductivity of fused quartz decreases with the decreasing of the mean particle size and with the increasing of the porosity. Simple modified methods to estimate the value of thermal conductivity are proposed, and had been demonstrated successfully by conducting fused quartz, carbonate sand and ottawa sand.

After the excavation of the rock , the rock mass stress state changes and the quality of rock mass damage deterioration. Rock excavation of spillway tunnel of the hydropower station may have some influence on the stability of the tunnel-face side slope. In this paper, combined with the engineering practice, based on the unloading rock mass theory and through two dimensional finite-difference method. Selected seven feature points near the excavation surface as monitoring points for calculation ,then calculated the effect on the stress and strain of the slope caused by the excavation of the spillway tunnel and analysed the changes in the distribution of the slope rock mass plastic zone and the point factor of safety. The results show that spillway tunnel excavation in excavated slope have some impact on the excavated slope stability, and it is more obvious for the effect on stability of excavated slope in considering rock mass unloading effect than do not consider the rock mass unloading effect.

After the excavation of abutment slope, the stress redistributed and the rock mass quality degradation damaged. According to fore-and-aft change of stresses for excavation, the authors divided excavation area and chose suitable mechanical parameters of rock mass for different excavation area. We used theory and methods of unloading rock mass mechanics and used elastic-plastic viscous damage mechanics model to give 2-D finite element analysis of stress and strain for typical profiles. And then we analyzed the changes of stress and deformation of the slope at nature and unloading conditions, analyzed deformation and stability at different reinforcement areas of the slope to choose reasonable reinforcement area. Strengthening plans of rock mass are analyzed and compared to choose reasonable reinforcement plan. The research results herein can offer beneficial reference for the design and the construction engineers.