The paper discusses the technology requirement,construction programs,methods and quality control measures on construction of jointing old and new concrete in Danjiangkou dam heightening project of Middle Line of the South-to-North Water Transfer Project.

Concentrated on the questions in heightening of dams, and focused on the practice of heightening of Danjiangkou dam, questions in heightening of concrete gravity dams were systematically studied such as connection of new and old concrete, temperature field, and thermal creep stress field by using of large F.

The stress distribution law of adherence of young on old concrete under splitting-tension load is studied as viewed from stress analysis.

Experimental research on the interfacial agent in bonding of the new-old concrete;

Experimental research on bond strength of new-old concrete with epoxy and sand transfer layer;

Shallow to talk the new-old concrete interface rough degree handles method and application