Study On Intelligent Evaluation Method Of Bridge Health State

For bridges in service, various safety problems may emerge due to numerous factors such as faults of design or constructions, effects of climate and surroundings, ever-increasing traffic and overloads. And these damaged bridges have little chance to be maintained and reinforced effectively, unless they are inspected and evaluated timely. Thus, in some extreme cases, bridges may fail suddenly in components, or even collapse entirely, causing casualty of human; let alone threat to traffic safety and loss of bridges life-span.This paper summarizes bridge evaluation into three different but linked parts: overall evaluation, damage evaluation and reliability evaluation. Then, an idea of intelligent evaluation is proposed in this paper. And research efforts are mainly focused on the following:1: Advantages of hierarchy analysis methodology for evaluating bridge condition are discussed. With analyzing different type of bridges, this paper set up hierarchy evaluating systems for various bridge types, classifying complex evaluation indices.2: Based on hierarchy analysis method, it presents fuzzy evaluating method for health evaluation of bridges, with fuzzy consistence matrix describing the uncertainty and fuzziness of expert judgments. Application of uncertain hierarchy-analysis method for overall health evaluation of bridges is also studied. Usually the weight domain obtained with usual measures can hardly be used in condition evaluation of bridge. So an optimal single-object model for calculating optimal weight is represented, and overall optimal searching is performed with real-number genetic algorithm. These two methods are verified by case analysis and comparison for a concrete bridge.3: Fuzzy reasoning method is introduced to express fuzzy and uncertain evaluation knowledge. Also application of fuzzy Takagi-Sugeno(T-S) reasoning...