Stability Problem In Slope Cutting Work And Ecology Recovery Work

For the natural slope cutting work, When the excavation position is on the slope surface will make the origin unity slope to different grade slope. There are two aspect of stability problem in this kind of cutting work. One is the stability problem of slope during or after cutting work. The other is stability problem of out-soil for recover or re-built the damaged ecosystem by excavation.1. Stability problem during cutting work of slopeIn this kind of engineering, the excavation position always on slope surface. A failure plane of variable slope angle will be developed during the course of slope cutting construction on a natural slope or after the construction. Slope cutting work will definitely change the boundary conditions of the slope, which will lead to the decreasing of slope stability or even failure of slope. According to results of centrifuge model tests and in site tests, there are two failure patterns of this slope. One is failure plane starts at top of the slope. The other is failure plane starts at surface of the slope. The critical depth of the two failure patterns were calculated by upper-bound theory in detail. Through comparison of the two critical depth in same conditions, discuss and define the conditions of the two failure pattern occurs. Then the critical depth, safety factor which design excavation depth less than critical depth and soil pressure which design excavation depth more than critical depth are given. It is meaningful to stability design of slope cutting work.2. Stability problem of ecology slope engineeringEcology slope engineering is which recover or re-built the damaged ecosystem by excavation using vegetation engineering and civil engineering method to make the ecosystem to a new balance. During out-soil re-vegetation in bare slope surface by cutting work. Study the effects on out-soil of boundary conditions geo-cell, concrete girt strip and so on. Discusses the effects of retaining structure on failure model of out-soil by model test method. Using limit upper-bound method to deduce the relationship between safety factor of out-soil and conditions (include clearance distance and method) of retaining structure. It is meaningful to put forward to optimally size of geo-cell and concrete girt strip.