The Analysis Of The Damage Of The Exiting Combined Truss Arch Bridge And Study On Its Strengthening

The combined truss arch bridge, which is originated by our country in the 19'80's, is a new type of bridge. Because of its advanced technology and cheap expenditure, it is extensively applied in our country and develops rapidly. The Yan Xi Bridge was built in March of 2003, and its main span is 180m. But nearly 4 years later after it came into use, some components of the bridge were damaged. Considering the security factors, the bridge needs to be maintained and strengthened in time.In this thesis, an integrated finite elements model of the bridge is built and the stress and load-carrying capacity in different cases are analyzed according to the condition of today's Yan Xi Bridge. The space finite elements model of the solid segment of arch crown is also established to analyze its local stress. The thesis also calculates and analyzes the free vibration models of the bridge, and the reaction to the structure when it is hit by the float in the river. At last, the main reasons of the deficiency are clearly analyzed. And according to the analysis and the service demand and considering the actual situation of this project, the strengthening scheme of the Yan Xi Bridge as well as the new materials and new techniques applied in it are introduced.The calculating and analyzing methods and the strengthening scheme mentioned in this thesis can be taken as reference to the similar bridges.