Strengthening treatment and analysis for the left bank abutment of Jin Ping Arch Dam

The Jin Ping arch dam foundation exhibits large differences in the stiffness between left and right bank due to a fault in the valley and unloading, relaxation and rock crushing effects in the left abutment. An extremely complex engineering problem appears by achieving mechanical balance for the dam body. To reinforce the left dam foundation concrete pads refilling faults, huge concrete piles and consolidation grouting together with grout and drainage curtains are investigated and executed. The numerical results show that these reinforcement measures for the excavated dam foundation improved significantly the rock mass deformability and its stability.
A suitable excavation sequence for reinforcement tunnels and caverns is studied and the stability of these tunnels is analysed. The influence of consolidation grouting on the slope stability is investigated by varying spacing and number of active grouting holes. During the construction of the reinforcement tunnels the vibrations induced by blasting are simulated and measured. For different distances between tunnels and slope to tunnels respectively, the maximum quantity of explosives for single drives is studied.