Study On The Dynamic Response Characteristics Of A Layered Rock Mine Slope Under Earthquake Actio

There are numerous landslide events caused by earthquakes,and landslide events seriously threaten the safety of people’s lives and property.Therefore,it is of great significance to study the dynamic response characteristics of slopes under earthquake.In this paper,the bedding slope of an open-pit mine in Zhaotong City,Yunnan Province is taken as the research background,and the nonlinear dynamic analysis under seismic action is carried out.Then the dynamic response characteristics of this kind of slope are revealed by comparing the dynamic response characteristics of homogeneous slope.Finally,the influence of structural plane parameters on the dynamic response of bedding slope is also explored.The specific work includes the following aspects:(1)In order to deeply understand the general situation of the study area,a series of field work such as field sampling,structural plane investigation and statistics,and geological data collection were carried out on the mine slope.Through the processing of the rock blocks retrieved from the site and the subsequent indoor rock mechanics test,the indoor rock mechanics parameters were obtained.Finally,the rock mechanics parameters of the slope were obtained by Hoek-Brown strength criterion.(2)According to the principle of nonlinear dynamic analysis and the characteristics of the slope,the boundary conditions and damping methods are reasonably selected and calculated.The design response spectrum curve is drawn according to the seismic fortification intensity,seismic grouping and other characteristic information of the study area.Based on the design response spectrum and the Pacific earthquake database,the real seismic waves that best meet the characteristics of the study area are selected.(3)The nonlinear dynamic calculation of homogeneous slope and bedding slope under seismic action is carried out,and the peak acceleration characteristics,spectrum characteristics and seismic wave propagation characteristics of different parts of the slope are compared and analyzed.Through comparison,it is found that there are some similarities in the dynamic response characteristics of the two types of slopes,such as the elevation amplification effect and the trend table effect of acceleration,but the differences also exist,mainly reflected in the strong fluctuation of the peak acceleration characteristics and spectrum characteristics of the bedding slope,and the propagation characteristics are also different due to the existence of structural planes.(4)Based on the control variable method,a series of numerical experiments were designed.Four gradients were designed for each influencing factor,and a total of 16 groups of tests were carried out.The influence of the change of structural plane parameters on the dynamic response of the bedding slope was explored from two aspects: the peak acceleration curve of the monitoring point in the elevation direction and the slope surface direction and the peak acceleration value.Then,based on the orthogonal test and the range analysis method,the sensitivity analysis of the structural plane parameters affecting the dynamic response of the bedding slope is carried out,and the order of the influence degree of each influencing factor on the dynamic response of the bedding slope is obtained.The order is structural plane cohesion > structural plane inclination > structural plane internal friction angle > structural plane thickness.