Moon Island Bridge Detection And Safety Assessment Study

Many bridges have been built in our country. During the bridge construction period, because technical level and design load level is low, highway traffic volume increases rapidly in recent years, these existing bridges get into overload condition. In addition, with unusual climate, frequent natural calamity and the bridges'external environmental deterioration, the damage and destruction to existing bridges is of increasingly serious, which have a lot of potential safety problems. Therefore, the comprehensive detection and safety evaluation research of the bridge has positive theoretical value and engineering application value.This thesis takes the Moon Island bridge in changsha, Hunnan as the research object. Comprehensive test and safety assessment for the bridge are carried out. According to the testing results, the force conditions of operational phase and pier 30 for the bridge are analyzed. The main contents of research are as follows:1. Background, significance and purpose of bridge comprehensive detection and security evaluation, research status and main contents of bridge detection, progress and main methods of bridge security evaluation, are introduced briefly.2. The comprehensive detections for the Moon Island Bridge including appearance inspection, the concrete strength, the concrete cover thickness, the steel corrosion, the deck disease, the static and dynamic loading testing are completed. Through the inspection, complete testing data, which provides reference for the safety assessment and the finite element analysis, are obtained.3. Based on testing results, the comprehensive evaluation method based on the weights of bridge components and the analytic hierarchy process(AHP) based on variable weights are used to evaluate the bridge security. Combining the two evaluation methods, reasonable suggestions for the bridge maintenance and management are put forward.4. On the ground of the testing results, the force conditions of operational phase of the bridge is analyzed by finite element method. The theoretical calculation of bottoms of the pier 30 and the pier 31 which have the most serious cracks is completed and the pier 30 is analyzed by using the software ANSYS11.0. By making a comprehensive analysis, the reasons leading to crack of the pier 30 are pointed out.