Study On The Bridge Performance Test And Evaluation Based On NDT

Bridges are the hinges of traffic system,playing an important role in national economic and society. The major part of existing bridges in our country is concrete bridges, having serviced for about 30 years. Damages, deteriorations and even disaters due to design, construction and long time service, such as cracking, corrosion, and load capacity deficiency, could be found easily on the existing bridges, which heavily influence functionality and safety of the structures in road systems. So it is necessary using state-of-art techniques to inspect and assess on-service bridges efficiently.Recently bridge accidents occur from time to time. Professional, expert and scholar all over the world have paid more and more attention to safety of existing bridges. Now the safety assessment of bridge structures have been intensely studied and becomes one of the hot topics in the field of bridge engineering in the past few decades. How to reasonable evaluate the safety of the bridges under the permissibility of economic and technique condition is an important and urgent task. To slove the problem this text which based on the existing safety evaluation methods carry out a deep study on the safety evaluation of the small-span bridges. The main works of this text are briefly mentioned as follows:1.The importance of bridge structure safety, the significance and goal of safety evaluation are expatiated, and at the same time, the development and actuality of safety evaluation at home and abroad are introduced.2. On the reinforced concrete bridge detection, in the reinforced concrete structure of various detection methods summarized in detail on the basis of the strength of concrete, cracks, defects and the depth of carbonation, steel corrosion extent of NDT methods.3.It indicates the basic principle of analytical hierarchy process and fuzzy comprehensive judgment, set up the whole and local fundamental framework of multilevel fuzzy comprehensive evaluation of existing concrete Bridges based on analytical hierarchy process (AHP).,carry out indicators to evaluate the level of vector method.4. It indicates a methods based on the load test the quality and appearance of the bridge integrated detection state of nondestructive testing, combins multi-level fuzzy assessment model, carry on a a bridge in service test and evaluation process of a specific analysis.5. A novelty evaluation method is proposed on the assessment of transverse connections of existing bridges using loading transvese distribution coefficients and measured deflections.