Stability Analysis Of High And Steep Rock Slope And The Optimization Of Anchor

The stability analysis on high and steep rock slop is one of the most important of the engineering geological programs in our country after the 20th century, 70 years. If handled improperly, it will cause serious economic losses and personal security issues. In this paper, there will analysis the stability of the slope formed after the artificial excavation. The slope is height of about 35 meters, slope angle is about 85°.There are many factors influencing rock slope stability, Rock stratum and rock property are not only essential of fundamental factors of the slope engineering, but also important basis for studies of slope stability. The studied slope is mainly composed by sandstone and mudstone, and they are relatively weak in physical and mechanical properties of rock. They will significantly decrease the mechanical properties especially after prolonged exposure or after contact with water, they are the decisive factors affecting slope stability. Geological structure is not developed in the exploration field. Most of rock is integrated and the combination between the different rock layers is bad or ordinary. Therefore, the structure of mass rock is a major factor in slope stability.In this paper, it begins with Stereographic projection method and flat-panel sliding method for analyzing the slope stability. The results show that slope needs reinforcement. Slope is mostly rock slope, the overall stability of slope mainly affects the joints structural plane. Because there are important high-rise buildings and meteorological observation equipments, the slope information should be strictly controlled. Therefore, it must be used a supporting structure which has relatively small deformation to ensure the buildings safety and normal use. Therefore, combining the standardized protocols and construction-related experience, there uses the anchor frame beam to reinforce the slope. In the finite element analysis, the results show that the slope stability safety factor is 1.14. Compared to the result of sliding plane method, the stability of finite element analysis is more stable, but slope is still needs reinforcement. According to the plastic deformation picture, the plastic deformation of soil extends from the top of the hill down to the department of strong weathered sandstone, and linking strong weathered sandstone layer, but did not continue to extend to the following medium weathering mudstone and harder breeze of sandstone and mudstone. Without careful analysis, we may have taken the slope of the failure mechanism as the "retaining wall buckling" style. But the harder of moderate weathered sandstone layer and slightly weathered mudstone layer are not similar to retaining walls bear the great "push" caused by the deformation of the upper slope. So, the slope failure mechanism is not the "retaining wall buckling" type. Further analysis shows that the slope failure mechanism belongs to slip - rupture - cut style.According to the plastic deformation curve, there are some flaws with the Design Institute of anchoring programs, especially in the long bolt design. At the same time the part of slop underlying the plastic deformation has also been reinforced, leading to slope safety factor is too large. It results an unnecessary waste in the project. Compared to the result of without optimization and with optimization, the finite element simulation calculations indicates that: after optimization, The slope safety factor reduced from 3.4 to 3.0, the pulling force of slope does not exceed the maximum pulling force of the stretch of rock stress, slope is still stable. It comes to the conclusion that its optimization program is scientific and rational.