关键词: 高寒矿区边坡, 坡向约束, SBAS-InSAR, 三维形变, 冻胀融沉

Abstract: The geological environment of the high-altitude cold mine slope is fragile,and the stability of the mine slope is easy to be destroyed under the action of frost,swelling,thawing and sinking.In order to obtain accurate 3D deformation characteristics under the condition of repeated freezing and thawing in high-altitude cold mines,and according to the features of slope materials sliding to the direction of maximum topographic drop under the action of gravity,this paper selects a certain slope in Jiama mine area in Tibet as the research object,takes slope direction constraint as prior condition,and constructs the 3D deformation model by jointing SBAS-InSAR.The results show that within more than two years the maximum cumulative sinking amount of the mine in east-west direction is -78 mm,the maximum cumulative sinking amount in vertical direction is -38 mm,and the maximum cumulative sinking amount in north-south direction is -25 mm.The main deformation occurs below the mining area,and the open-pit mining area is relatively stable.Through cutting out the mine profile line to analyse time-space evolution of sliding slope,it can be found that displacement gradually decreases with depth increase,and frost,swelling,thawing and sinking only occur on the surface of active layer.3D deformation analyses show that frost,swelling,thawing,and sinking and concentrated rainfall induced by temperature change have greater influence on the deformation of the slope in vertical and east-west directions,while the influence in north-south direction is relatively small.The calculation results of this paper are reliable,which provides some reference value for large-scale remote sensing slope monitoring in high-altitude cold mine areas.

Key words: slope of alpine mining area, aspect constraints, SBAS-InSAR, 3D deformation, frost heave and thawing