Abstract:The failure of anti-slide pile in earthquake is one important factor that aggravates the harm of mountain hazards. However

the mechanism of it and its response mechanism to seismic wave are not clear at present

and the interaction mechanism between anchor system and seismic wave can’t be resoluted. Therefore

based on energy theory

taking the upper bound theorem used in limit analysis as measure

and assuming the sliding face as arc

the safety of anchor system was defined

and then the mechanism of energy input and dissipation under earthquake was studied. Furthermore

the characters seismic wave which induces the damage of anchor system was also analyzed

and the calculating formulas were suggested. At last

an example was given to show that the failure mechanism of anti slide pile is the result of discontinuous damage accumulation under seismic load with special direction and value.