Study On Deep Anti-sliding Stability And Foundation Treatment Measures Of A High Gravity Dam

Gravity dams require high quality of dam foundation and strength of rock mass.If there are defects in dam foundation,such as weak structural plane,gravity dams may slide along the defects of dam foundation to produce shallow or deep sliding..Therefore,it is of great significance to study the deep anti-sliding stability of gravity dam foundation.Taking a retaining dam section of a gravity dam to be built as an example,the anti-sliding stability of the foundation of the gravity dam before and after treatment is analyzed and evaluated by using numerical analysis software FLAC3D and EMU,and the selection of reinforcement measures for the dam foundation is discussed.Before the reinforcement of dam foundation,the limit equilibrium analysis program EMU is used to analyze and calculate the sliding stability of gravity dam under various working conditions and possible sliding modes.The safety factor of anti-sliding stability is between 1.79 and 3.19,which is too low to meet the safety requirements of relevant codes.In this paper,three kinds of reinforcement measures are put forward,and the anti-sliding stability of dam foundation of the three reinforcement measures are analyzed and evaluated by the limit equilibrium method and the strength reduction finite element method.After the treatment of downstream concrete cover,the safety factor obtained by limit equilibrium method is increased,ranging from 1.93 to 4.08,and the safety factor obtained by strength reduction method is 3.7.After adopting the engineering treatment measures of alveolar and downstream concrete cover,the safety factor obtained by limit equilibrium method ranges from 2.90 to 4.1,and the safety factor obtained by strength reduction method is 3.7.When adopting the engineering treatment measures of downstream concrete cover,alveolar and anti-shear tunnel,the safety factor obtained by limit equilibrium method ranges from 3.03 to 3.13,and the safety factor obtained by strength reduction method is 3.7.The result of the paper shows that the combined reinforcement scheme of concrete cover,alveolar and anti-shear tunnel can make the safety factor of anti-sliding stability meet the requirements of the code.