Analysis Of Concrete Structure Based On Damage Mechanics

The material or structure used in practical engineering away have initial damage which gradually devepop from beginning of distortion to failure, in this process polymerization and development of micro-cracks will cause formation and expand of macro-cracks. The damage mechanics is just a science that study the process and law of the material's destroy caused by microbug.In civil engineering, concrete as a sweeping adopted material inevitably have initial damages during construction .which will further evolve and develop under exterior loads. In this paper, in order to carry out damage analysis of concrete structure , concrete's initial damage and damage threshold value that is some significant to the establishing of concrete damage model are studied through the stretch and compress experimentation of concrete .In addition ,in view of significant of concrete damage failure in analysis of structure, in this paper rule of concrete damage failure based on both definition of damage energy release rate and Drucker-Prager rule are also discussed.Concrete's initial damage and damage threshold value gained through above experimentation is imported to exponent function damage model advanced by professor Xu Dao-yuan , and finite element equation included influence of damage is derivated .Based on great current finite element program-Marc , damage compute program is worked out and testified through examples. This make damage compute possible and is significant explore for damage mechanics's application to civil engineering.In this paper the author assume that micro-cracks will occur in the concrete structure after damage threshold value is reached. Because of existence of micro-cracks, it is very difficulty for us to analysis concrete's damage. The numerical method for analysis of damage failure is put forward through combination model of exponent function damage with model of smeared crack model. The example computed in the chart show that the method is reasonable .Finally ,the damage analysis of Suofengying dam is carried out ,and reasonable results are gained.