Research On Compositive Assessment System Of Prestressed Concrete Continuous Rigid-Frame Bridge

As the structure of bridges becomes naturally old and is accumulatively damaged, and the increase of vehicles and the deficiency of bridge maintenance have caused bad effects, it is commonly known that most of the existed bridges cannot satisfy the requirement. So the engineering field has paid great attention to the assessment methods and reinforcement techniques of bridges gradually.Based on earlier research, a system is established and a software is programmed, for the assessment of prestressed concrete continuous rigid-frame bridge, by improving the assessment methods for existed bridges and integrated with the trait of prestressed concrete continuous rigid-frame bridge. The main contents of the thesis are as follows:Firstly, the purpose and meaning of bridge assessment are discussed, its basic concepts are explained, the assessment methods and assessment system for existed bridges are reviewed and evaluated in detail, and the issues to be studied are elicited consequently.Secondly, the basic concept and methods of fuzzy set, and the basic principle and approach of fuzzy compositive assessment, and the methods that deals with the results of fuzzy compositive assessment are explained; The methods to calculate indicator weight by analytic hierarchy process and bringing group judgements in it are introduced; The variable weight principle and its application in fuzzy compositive assessment are discussed.Thirdly, the compositive assessment model of prestressed concrete continuous rigid-frame bridge is buit up; The way to determine the rank vector of lower level indicator is presented; The application of multilevel fuzzy compositive assessment methods in evaluation of prestressed concrete continuous rigid-frame bridge, which based on analytic hierarchy process and variable weight principle, is discussed.Fourthly, based on Visual C++ 6.0, the software of compositive assessment system for prestressed concrete continuous rigid-frame bridge is developed preliminarily.Finally, the application result of the compositive assessment system, which is buit up for prestressed concrete continuous rigid-frame bridge, is tested by an example.