Steel Arch Bridge Detection And Reinforcement Technology

Along with rapid development of our economy, the road traffic volume and load increasing in large scale, bridges constructed in the 1960s-70s have damaged in various degree, which becomes an obstacle of transportation in China. The arch bridge is with good-looking, solid bridge construction, strong bearing capacity, convenience in drawing materials and low cost in construction and maintenance, the number of which is large in old bridges. The existing bridges reinforcement will not only reap significant economic benefits, but also result in good social benefits by saving a large amount of construction investment, which improves the situation of a serious insufficiency of construction funds for a long time. Therefore, the detection and reinforcement of the bridge is important for the bridge engineering.This thesis takes the Hutian bridge in Huaihua, Hunan, a reinforced concrete rigid frame arch bridge with 50+17×16m pre-stressed reinforced concrete hollow slab as an object. Through the on-site test and the finite element model analysis to study the results of detection and the FE model analysis, the enlarging section method and the externally bonded CFRP composites method are studied. The main contents of research are as follows:1. Some kinds of diseases and their characteristics are summarized, and detection and reinforcement methods against these diseases by analyzing of the causes are introduced.2. Some commonly used methods of reinforcement of old bridges are described, including the design method, the construction techniques, the merits and demerits and the application range. Then, some comparisons are made from the theory and construction methods between the enlarging section method and the externally bonded CFRP. The evaluation system after reinforcement is briefly introduced.3. The detection of the Hutian Bridge from the appearance, the static and dynamic loads is completed. Based on the structure characteritics of the Hutian Bridge, the working model of the bridge is established by using the ANSYS software, and its working state is conducted a simulation analysis. The results both in-situ detection and theoretical analysis are showed compressively, and the diseases are pointed out, which offers reasons for the reinforcement.4. On the ground of the test and theoretical analysis results, a reinforcement design is proposed for the Hutian Bridge. Subsequently, the mechanic properties of the bridge are analyzed by the ANSYS, and the appraisal of the working condition after reinforcement is followed. KEYWORDS arch bridge diseases, detection, the enlarging section method, the externally bonded CFRP composites, FEM...