Study On Safety Of Existing Dam And Bedrock Due To New Dam Foundation Excavation

Taking One Dam Comprehensive Reinforcement Program for example, this paper analyzes the displacement field, the stress field and the stable safety effect in dark-and-light layers of typical section for the exiting dam (old dam) due to new downstream dam foundation’s excavation. Based on three-dimensional finite element modal, this paper mainly discusses and evaluates the dam body’s security changes after changes in force state of old dam due to new dam foundation’s excavation for the anti-sliding stability effect in foundation plane and dark-and-light layers of overflow section, the results of rigid body limit equilibrium method and finite element method are list out. Considering the effect of weak structural plane in water retaining section, the results of three-dimensional nonlinear analysis is analyzed to obtain some significant conclusions.The computation results show that the excavation of the new dam’s foundation will affect the stable safety of the exiting dam to a certain extent. However, it won’t change the old dam’s security state obviously. The new dam project can be constructed well in theory as well as the supporting measures, construction procedure and observation works well. The research provides lots of important technical information and practical experience for more similar projects in the future.The following aspects are studied:Chapter1expatiates on the academic background and practical meaning of the subject. Chapter2shows the constitution of the materials, the basic theory and method of non-linear finite element and the method of simulating progressive failure process using FEM. The effect of the displacement field, the stress field and the stable safety for the old overflow section due to new downstream dam foundation’s excavation are discussed in Chapter3.Taking vertical joints in old dam into account, the displacement field, the stress field and the stable safety for the old overflow section are ulteriorly studied in Chapter4. The water retaining section which contains weak structural planes is the weak of the old dam. A non-linear finite element modal of water retaining section has been carried on to mainly discussed in Chapter5. In the last of article, analysis results about security influence of both old dam and bedrock due to new dam foundation’s excavation are summed up and some suggestion and prospects for the future research work are put forward.