Abstract:On the basis of the phenomena of slope shattered deformation and failure after 5·12 Wenchuan great earthquake,the effects of body wave and surface wave in the earthquake are analyzed,and the mechanical mechanism of slope shattered deformation are studied.It is considered that the effect of seismic waves caused the alternate action of the tension stress with values and direction constantly changing acted on the rock and soil mass of slope surface layer,especially on the slope shoulder,the characteristic on perpendicular plane showed overall dynamic change and resulted in the rock and soil mass on shoulder appeared revolution-dump,positive and inverse tension action.Meanwhile,the following shear action,cracking and crushing occurred.The shear action was more concentrated on slide surface.In addition,the bulge tension and torsion forces acted together on the slope surface also.In this paper,seismic wave effect is divided into four kinds of forms： the tension-shearing rupture effect,the interface dynamic stress effect,the potential wedge splitting effect,and the super interstitial hydraulic or pore water pressure excitation mechanism.The analysis results are well in accordance with field phenomena and the result of vibration simulation model,provided an important guide for the post-disaster reconstruction and disaster prevention and mitigation.
