The massive Shaweitaizi landslide in the Jinsha River was formed about 40

000 years ago

and its existing volume is about 2.69 × 108 m3.The material structure of the accumulation body shows typical collapse landslide characteristics of strong dynamic triggering.Further analysis results of discrete elemental inversion show:The extensive structural surfaces in the mountains are the key factors on slope stability controlling.The ultimate dynamic acceleration of the slope rock mass is a

max

=0.4 g

and the critical dynamic load for collapse flow formation is a

max

=1.3 g.The mechanism of landslide formation is that the bottom shear-slip-locked section cannot resist the pushing

of the upper rock mass under the action of strong earthquake

resulting in buckling failure.During the sliding of the landslide

the front slide body decelerated gradually with the action of bottom friction

but the mid and back materials driven by a strong earthquake still had great speed.The mid and back materials hit the front material and formed debris flow

which is the key reason that the front materials of the landslide had a great kinetic energy.The front deposits of the landslide transported remotely across the riverbed and even climbed to the opposite slope to a height of 200 m.