Study On Junction State Of Fresh-old Concrete And Safety Evaluation For Heightening Project Of Danjiangkou Dam

In the dam heightening project, Problems of bounding between freshand old concrete are one of the main difficult technicalproblems;Simultaneously, fore and after the dam heightening, variation ofthe vertical stress of the dam heel and the joint work of the new and oldsection of the dam are also the main problems that must be considered.For making a further study of above questions, Take the 7 # dam asthe research object, an three-dimensional emulation computation onthermal stress of the dam was carried out according to the preliminarydesign of construction plan, Simulated bounding surface between freshand old concrete using contact elements,It Analysis Problems of the damwith the new and old concrete surface working status,the joint work ofthe new and old section of the dam, the variation of the vertical stress ofthe dam heel fore and after the dam heightening in Construction periodand run-time.Through the simulation, It gives the old dam stable temperature field,the steady-state temperature field after increasing the height of the dam,new and old concrete with the opening of heterozygosity and contactsurface ratio, Chung stress before and after the dam heightening, toe ofthe Stress of New and old dam, etc. It is concluded that: the verticalstressstate of the dam heel was improved after the heightening compared withthe results before. The joint face is partially open and partiallyclose atanytime, but it can pass the horizon pushing force effectively.