From the point of view of system theory

the landslide hazard system includes two subsystems: subsystem of hazard and subsystem of stricken. The consequence of landslide hazard is based on the interaction of these two subsystems. previous studies concenerate on evaluation of landslide stability. Hence

the study of a typical element at landslide risk is focused. And a method to calculate failure probability of typical element (frame structure) at landslide risk is discussed. Furthermore

the influences of both impact force and impact resistancecapability of element at risk on failure probability are analyzed

which shows that

for each elements at risk

the landslide impact area can be divided into absolutely dangerous zone

relatively dangerous zone and absolutely safety zone. In addition

with the condition that the structure failure probability is above 50%

as the variability of impact force increases

the structure failure probability decreases; with the condition that structure failure probability is below 50%

as the variability of impact force increases

the structure failure probability also increases.