Study On The Evolution Law Of Slope Cumulative Damage Under Multiple Mine Earthquake

There are as many as tens of thousands of mine earthquakes in Fushun.The earthquake disasters can cause surface buildings to shake or even damage,and seriously threaten the lives and property of the people in the mining area,causing the mine earthquake disaster to evolve from a mining safety issue to a public safety issue.When studying the slope deformation and failure laws of Fushun West Open-pit Mine,it is not only necessary to study the landslide disaster caused by a single strong earthquake,but more importantly,to study multiple low-strength mines.The earthquake caused structural weakening and accumulated damage to the slope,and finally triggered a landslide disaster.Aiming at the cumulative damage problem of slopes under frequent mining earthquakes,this paper takes the south slope of Fushun West Open-pit Mine as the research object,combined with the on-site geological survey,data analysis and investigation of the West Open-pit Mine,and adopts the CDEM.Carry out the numerical simulation analysis of the deformation and failure of the bedding rock slope under the action of the mine earthquake,study the dynamic response of the slope under the action of the earthquake and the deformation and failure of the south slope of the Fushun West Open-pit Mine under the action of frequent mine earthquakes,and combine the cumulative damage theory with Combining numerical simulation methods to study the cumulative damage of slopes under the action of mine earthquakes.The main research contents and results of this paper are as follows:(1)Define the damage inside the element body by tensile stress and shear stress,and derive the constitutive relationship of elastoplastic damage inside the element body according to the Mohr-Coulomb criterion;define the damage variable of the interface spring element by the strain intensity distribution model,and derive at the same time Describe the damage constitutive relationship of the progressive failure process of the rock mass.(2)The internal acceleration curve of the bedrock under earthquake action is divided into four stages: static loading stage,earthquake initial stage,earthquake superimposition stage,and earthquake termination stage;the internal acceleration curve of dangerous rock is divided into three stages: static loading Phase,earthquake phase,earthquake termination phase.Dividing the internal time-history acceleration curve of the slope into stages can effectively distinguish the change of the internal point acceleration of the slope,and it can be clearly seen that the internal point acceleration of the slope changes with the seismic loading.(3)The magnitude of the ground motion represents the intensity of the earthquake.The displacement of the slope surface of the slope has a linear relationship with the magnitude of the ground motion.The greater the magnitude of the ground motion,the greater the displacement of the slope surface;when the slope response acceleration amplitude is maintained When they are consistent,the input ground motion frequency is inversely proportional to the slope displacement;the duration of the ground motion has a greater impact on the slope deformation.The slope deformation increases with the increase of the earthquake time.As the earthquake continues,the slope The internal energy continues to increase and internal damage gradually accumulates,eventually leading to instability and failure of the slope.(4)When analyzing the damage of the slope,the damage of the unit is divided into tensile failure and compression-shear failure.The failure state is divided into current failure and past failure.Once the unit is damaged,it will not return to its original state.The elements are both tensile damage and compression-shear damage and destruction at the same time.(5)The cumulative damage of the slope is defined by the proportion of the total damage and damage area of the slope element,and the cumulative damage curve is drawn at the same time,which can better represent the cumulative damage process of the south slope of the Fushun West Open-pit Mine under the action of the mine earthquake.At the same time,the slope failure criterion is defined to provide a reference for the deformation and failure of the slope.There are 105 figures,8 tables,and 72 references.