The analysis of slope stability of reversed multilayered binary soil hybrid structure

摘要

The body structure type of layered structure in II-B area of north slope was identified and classified based on the background of Shuichang Iron Mine high-steep slope.The generalized model of slope was established in this region and internal stress and displacement distribution features of reverse layered soil-rock aggregate dualistic structural slope were analyzed, through the main failure mode of this kind of slope was obtained and the high-steep slope stability in II-B area for dynamic excavation on condition of complex tectonic stress field was analyzed emphatically.The results indicated that: 1.The dual structure of earth-rock aggregate slope was classified according to the relationship between slope strike of dualistic bedrock structure and rock strata.It was helpful to improve the accuracy for generalized slope model identification.2.On the slope surface and the top of the slope with reverse layered dualistic soil-rock structure, the maximum principal stress paralleled to its face and the minimum principal stress went perpendicular to its face.The minimum principal stress would change to tensile stress when it went beyond zero.The phenomenon of the stress concentration appeared at toe of the slope.The maximum principal stress value increased prominently along the tangent slope foot.The minimum principal stress value significantly reduced and even changed to the tensile stress along the radial direction.The maximum horizontal displacement occurred at top of slope surface.The landslide type was more prone to bending toppling destruction.3.In the whole mining process, the influence range of slope excavation developed simultaneously along the slope surface direction and perpendicular to the slope surface direction, and formed a circular destruction at the bottom of slope surface.The slope can fail easily if it is covered with hard rock.Moreover, when shear outlet consisting of the mudstone and weak rock that are located near the slope edge, the overlying loose layers slides more easily.