The outlet of the diversion tunnel #2 of Zipingpu Hydraulic Project is located on downriver side of the right bank chine. It is under the trough valley formed by the huge fault zone. It happened several times that the overburden layer of the slope slide during the construction. The safety of people lived near the project was threatened and the construction progress of the whole project was badly affected. Many kinds of methods were synthetically taken to maintain the stability of the slope. FLAC3D is used to simulate the excavation with the prestressed cables and friction piles. The effect of the support is analyzed from displacement field

stress field and other aspects. The results show that the support can remarkably control the deformation of the slope and the slope was stable after reinforce.