Study on dynamic response of unequal width platform cutting slope under earthquakes
The design of unequal width platform is one of the effective methods to improve the dynamic stability of high cutting slope in cataclastic rock mass.Under the background that the width of standard platform should not be less than 2 m,it is of great engineering application value to study the dynamic response characteristics of this type of slope.The PGA amplification factor,plastic deformation zone and the maximum shear strain of the platform position of the three-level stepped slope are calculated by FLAC3D finite element software.Then,based on the numerical simulation results,a large-scale shaking table physical simulation test is designed to carry out the research on the deformation and instability characteristics of the non-equal-width stepped slope and the change of PGA amplification factor.The slope failure degree caused by the width of the two-level platform is analyzed,and the design suggestions of the cutting slope engineering are put forward.The numerical simulation shows that the PGA amplification coefficient decreases first and then increases with the increase of the width of the intermediate platform.Considering the platform segmentation effect,the width of the secondary platform of the project is recommended to be 4 m.The physical test shows that the slope is prone to stress concentration at the platform.The platform segmentation effect causes the slope to gradually decompose into local damage.Progressive deformation and failure occur under earthquake action,which can be divided into slow deformation,accelerated deformation and instability failure stages.The research results provide a basis for the design of this type of cutting slope platform.
NETL
NSTL
万方数据
维普
