| With the promotion and implementation of the western development strategy,many construction projects are faced with the problem of instability of high rock slopes under seismic dynamic load.So far,there has been little consideration of the seismic dynamic characteristicstraveling wave effect-in the analysis and evaluation of the dynamic response and stability of high rock slopes.Therefore,it is undoubtedly of great theoretical significance and engineering application value to carry out the research on the dynamic response law and stability of high rock slope under the seismic action considering the traveling wave effect.On the basis of previous research,this article establishes a generalized rock high slope model based on the dynamic time history analysis method,with a focus on considering the dynamic response and stability of rock high slopes under the traveling wave effect of ground motion.It is coMPared and analyzed with the situation where the traveling wave effect of ground motion is not usually considered.Secondly,the optimal damping form of FLAC3D dynamic calculation is analyzed,and finally,an engineering example is applied.The main work and research results are as follows:(1)Firstly,the dynamic equilibrium equation of the input seismic traveling wave effect is derived,and numerical simulation is used to coMPare and analyze the instability mechanism,evolution process of sliding surface,and differences in dynamic response of rock high slopes considering the traveling wave effect of seismic motion and without considering the traveling wave effect.The results indicate that under the action of seismic motion,whether under traveling wave excitation or uniform excitation,the sliding surface of rock high slope instability and failure is composed of tensile cracks formed by tensile failure at the top of the slope and shear sliding surfaces formed by shear failure inside the slope.And the sliding surface is not formed instantly and has a certain degree of progressivity.(2)The physical and mechanical parameters of rock mass,such as density,modulus of elasticity,cohesion,friction angle,and Poisson’s ratio,are discussed in detail for the dynamic response and stability of high rock slopes under ground motions;The effects of ground motion parameters such as traveling wave velocity,intensity(amplitude),frequency spectrum,and duration on the dynamic response of high rock slopes are studied;The study on the dynamic response of high rock slopes to geometric parameters such as slope height,slope angle,slope surface,and slope shape of slope models has been carried out.The research results show that the safety factors of slopes under uniform ground motion excitation are higher than those under traveling wave excitation.The main reason for this is the mutual interference of seismic waves in the propagation process,indicating that the safety factors of slopes under traditional uniform ground motion excitation tend to be conservative.(3)The optimal mechanical damping form under dynamic analysis and the dynamic response rules under different damping ratios were studied and analyzed.Research shows that Rayleigh damping and local damping not only effectively reflect the energy dissipation law of rock and soil movement,but also have a more ideal convergence state coMPared to the dynamic response of hysteretic damping(Default,Sig3,Sig4,Hardin).When conducting dynamic analysis,it is recommended that scholars choose Rayleigh damping and local damping as a good choice for damping models,while the selection of hysteretic damping should be cautious and determined based on actual conditions.(4)Through a practical engineering case-Woqian landslide,the dynamic response under ground motion is briefly analyzed.The results show that the Woqian slope is bounded by the boundary between limestone and slate.Shear failure mainly occurs in the limestone area,while tensile failure mainly occurs in the slate area. |
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