The Safety Evaluation And Strengthening Method Of Two-Way Curved Arch Bridge

Two-way curved arch bridge was created in1960s in China. This kind of bridges has the characteristics of convenience construction, shorter construction period, fewer raw materials, and lower requirement for the foundation bearing capacity. This new bridge style is promoted rapidly in whole country at the time of the backdrop, and has made great progress of the development of China’s transport system. But due to the increase of traffic flow and vehicular load caused by the development of traffic, and the inherent defects> the constraint of design and construction level, different degrees of diseases is found in most two-way curved arch bridge, some of them were collapsed. So the safety evaluation and strengthening of the existing two-way curved arch bridge is imperative.In this thesis, the strengthening and reconstruction project of Taihe Bridge in Xichang is used as an example of engineering practice. During the process of reinforcing design, the theory of safeity evaluation and the principles in strengthening design has been used. The comparison of bearing capacity and integrity between the original structure and the reinforced one is proved that the hooping bars method of strengthening design is effectively. And these conclusions can offer reference for same projects.First, the origin and characters、using actuality and development trend were summarized by looking up the relevant documents, and the research status and development of safety evaluation theory at home and abroad was introduced.Then introduced the principles in the design of strengthening, summarized the common diseases of two-way curved arch bridge and analysis the reasons which caused these diseases. The common method of reinforcing for two-way curved arch bridge was summarized based on the predecessors’work.In the safety evaluation of Taihe Bridge, three methods have been used. The hooping bars method was established according to the conclusion of evaluation. Then a strengthening bridge FEM model was established according to the construction stage. Based on the present numerical results, whether the bearing capacity and the integrity of structure can meet the requirements was discussed. And at last, the reinforcement effect was evaluated by load tests.