Three-dimensional dangerous sliding surface of slopes with a weak layer in open pit construction and stability calculation
To solve the problem of three-dimensional stability analysis of slopes with weak layers in open-pit coal mines,we propose a method for constructing dangerous sliding surfaces of slopes with weak layers.Through spatial geometric operations such as rotation and translation of the standard ellipsoid,and slope interpolation,a dangerous sliding surface of the ellipsoid slope controlled by six parameters including the three semiaxes Ra,Rb,Re,sliding point xa,sliding point xb and rotation angleθ of the ellipsoid is generated,and then,according to four different conditions,the dangerous sliding surface of the ellipsoid slope and the structural surface of the weak layer are selected and combined with interpolation to construct a three-dimensional dangerous sliding surface of the slope with the weak layer;Based on the basic principle of residual thrust method,a three-dimensional residual thrust method calculation program is compiled to calculate the slope stability coefficient,and genetic algorithm is used to search the most dangerous sliding surface;The method is verified by using classic calculation examples.The sliding mass width is 5 m,15 m,30 m,and 50 m respectively for calculation.The three-dimensional stability calculation results are 2.358,1.877,1.754,and 1.715 respectively,and the two-dimensional residual thrust method calculation results are 1.517.It is concluded that the stability coefficient of slopes with weak layers gradually decreases and gradually approaches the two-dimensional calculation results as the sliding mass width increases;Taking an open-pit coal mine in Xilinhot,Inner Mongolia Autonomous Region as an application example,the method was applied to establish a three-dimensional model of the slope with weak layers in the northeast side of the open-pit coal mine.The landslide mode was determined to be the combined sliding with the 1-1*coal roof as the weak layer.The three-dimensional stability of the study area was calculated,and the calculation result was 1.321.There were five different lithologies in the sliding mass,and a total of 5425 rock blocks were generated to verify the adaptability of the method in the actual project.
NETL
NSTL
万方数据
维普
