Study Of Damage Evolution Law Of Inclined Slope Containing Multi-weak Strata Under Earthquake Action

China is located in earthquake-prone areas,and the problem of earthquake resistance has attracted much attention.The inclined slope with multiple weak layers is one of the more common slope types.Because it is prone to overall bedding slip,its stability has attracted much attention in many slope engineering projects.Under the action of earthquakes,it is more likely to cause large-scale earthquake disasters and cause significant loss of life and property.Due to the particularity of the shape of the rock stratum and the existence of the weak layer,the rock slope with weak layer usually has different manifestations when it is destroyed.Based on the shear damage experiment of the weak layer specimen,the damage model of the inclined slope with weak layer is established by using the secondary development of FLAC 3D,and the dynamic response and damage evolution law of the inclined slope with weak layer under the action of earthquake are explored.The slope with weak layer in the south of Fushun West Open-pit Mine is taken as the actual working condition to study,which provides the basis for further study of the instability failure mechanism and prevention of such slopes.The main research contents include :(1)The uniaxial compression and cyclic loading and unloading tests of rock mass specimens with a single weak layer were carried out to determine the compressive strength of rock mass with a single weak layer.The stress-strain curve and the damage factor D-loading times T fitting curve of the specimen with a single weak layer were analyzed.With the increase of the dip angle and thickness of the weak layer,the damage fitting curve gradually increases,and the influence of the thickness is greater than that of the dip angle.The numerical simulation of the slope with a single weak layer shows that the damage of the slope with a single weak layer is not as obvious as the thickness.As the thickness of the dip angle increases,the damage evolution law of the slope with a single weak layer gradually increases.(2)The dynamic response law and damage evolution law of the whole slope and the local part of the slope with different dip angles,thickness and intersection angles of double weak layers are analyzed.The maximum displacement of the whole slope in X direction increases with the increase of dip angle of double weak layers,and the damage variable also increases.The X horizontal displacement at the intersection of double weak layers and slope increases with the increase of thickness,and the damage evolution law decreases first and then increases.The vertical displacement at the intersection of double weak layers increases with the increase of intersection angle,and the value of damage variable D increases gradually.(3)The damage evolution process of multi-weak layer slope under earthquake is studied.The dip angle,thickness and spacing between different multi-weak layers are studied.The closer the intersection of multi-weak layer and slope is to the bottom of slope,the larger the horizontal displacement of monitoring point is.The two regions between the multiple weak layers are the regions with the largest horizontal displacement,and increase with the increase of the thickness of the multiple weak layers.The smaller the distance between the three weak layers,the clearer the horizontal dynamic response law.With the increase of dip angle and thickness of multiple weak layers,the damage law of slope increases first and then decreases.When the spacing of multiple weak layers is 60 m,the damage variable D reaches the maximum.(4)The dynamic response law and damage evolution law of E2000,E2200 and E2400 in the south section of Fushun West Open-pit Mine under seismic action are studied.The displacement of X horizontal direction increases gradually with the decrease of elevation in the upper part of the weak layer of E2000 section slope.The acceleration of the monitoring points on the weak layer of the E2200 profile slope increases with the decrease of the elevation.The upper part of the E2400 weak layer slipped first,and the displacement to the lower right at the intersection of the weak layer and the slope top was the largest,and the slope top was the first to be damaged.The slope damage variable curves under the three working conditions all show an upward trend with the increase of ground motion duration,and the damage evolution law gradually increases.The paper has 133 figures,16 tables and 72 references.