Study On The Characteristics Of Rockfall Movement And Prevention Measures Of Xiagongbao Collapse In Xingshan County

Xingshan County of Hubei Province belongs to Daba Mountain system,the mountain range is mostly east-west extension,the overall terrain is west,north,east three sides high,south low,showing high slope steep topographic and geomorphological characteristics.In Xingshan County,the geological conditions are complex and the geological environment is fragile,especially the large number and wide distribution of dangerous rocks,which can easily induce geological disasters such as rock and rolling stones.High-level collapse and falling stones often cause serious losses and major threats to residential houses,traffic roads,land,reservoirs and so on in the middle and lower part of the slope body.However,due to the sudden,unpredictable and destructive characteristics of rockfall movement,it is often difficult to take accurate and efficient prevention and control measures in advance.In view of this,this paper takes the collapse of Xiagongbao,a typical high dangerous rock collapse in Xingshan County,as the research object.On the basis of field investigation,data collection and analysis,numerical simulation is adopted to reveal the collapse mechanism on the basis of the analysis of the characteristics and influencing factors of the collapse source.The main research contents and achievements are as follows:(1)Based on the field survey,three parameters of rock fall motion characteristics are selected: the angle of initial collision surface,the quality of rock fall and the height of rock fall.By means of orthogonal test,difference analysis and variance analysis,the influence relationship between the two motion indexes and three parameters is obtained.At the same time,the law of interaction between the three parameters is obtained.(2)he lateral collision occurs during the falling rock movement of Xiagongbao,the trajectory of which is a near broken line type,the magnitude of the deflection angle during the transverse collision of the falling stone is studied by Rocfall the method of piecewise superposition simulation,and the new falling rock movement trajectory and the range of falling rock are drawn under the change of different falling stone quality parameters,Compared with the trajectory and the distribution range of rockfall,it is concluded that the simulation path is not different from the actual path,and the two rockfall ranges have a large overlap area,which proves the rationality of the Rocfall piecewise superposition simulation method.It can optimize the traditional rockfall simulation.(3)According to the superposition simulation method,the data of the minimum bouncing height and the total kinetic energy distribution range of the falling rock can be quantified,and the type of passive protective net and the information of its arrangement height,length and position can be determined together rock distribution range.By using the method of piecewise superposition simulation and parameter sensitivity analysis,this paper systematically analyzes the variation of the angle of the falling stone in the transverse collision process under different mass parameters.Then the trajectory of falling stone and its possible range are obtained by angle offset.Rocfall method can make up for the limitation that the traditional two-dimensional simulation method can not be measured horizontally,so that the simulation is closer to reality,and more targeted prevention measures can be put forward accordingly.