Aiming at the widespread problem of poor stability about dump with weak basement

based on the analysis of the instability of the main influence factors and five kinds of common instability mode about the dump

combined with the engineering geological practice of south slope in south dump of Shengli eastern NO.2 surface mine

based on the strength reduction theory

the deformation-failure rule and stability of basement and slope rock mass in loading dump were analyzed by large geotechnical numerical simulation with FLAC3 D.The landslide model and the final dumping height in south slope of south dump were researched.The research results show that the deformation-failure is mainly influenced by the gravity of the dump

and the maximal displacement of the basic weak layer increases linearly with the increase of the dumping height and the deformation under the weak layer of the rock mass is small.The landslide model is shear circular sliding along the basic weak layer and it can add one dump bench on the original design in the south dump of Shengli eastern NO.2 surface mine.It improves the utilization of dump space and provides reference for the similar dump slope designing.