Research On Health Evaluation Of In-service Stone Arch Bridges Based On Fuzzy Analytic Hierarchy Process

Along with the rapid economic development, a lot of bridges have beenconstructed in China in last60years. Considering the design load standards, the designtheory and construction qualities of the time, recently many of these bridges arebecoming to be decreased in such aspects as materials, structural members, loadcapacity and serviceability because of the bad influences of natural disasters,circumstance change, artificial damage, increasing load standards and so on inlong-term service. So the normal operation of these bridges is impacted and the safetycondition of bridges and communications is influenced heavily. And bridge collapseswill bring serious results, which include not only the large economic loss and humancasualty but also important bad influences on bridge construction and development ofsociety. Therefore it is becoming an urgent task recently and long-lasting time in futureto adopt scientific approaches to evaluate the safety state of these in-service bridgesobjectively and accurately so that rational maintenance, management and alteration areimplemented for these bridges based on the evaluation. This task is meaningful inreality, society, economy and application foreground.The evaluation theory on bridges based on analytic hierarchy process is developedwell and the interrelated theory such as grey associated analysis theory and changedweight theory is developed rapidly. There are still many researches on bridgeevaluation based on fuzzy analytic hierarchy process and many valuable achievementsare obtained domestic and overseas. However relative formal specifications have notbeen constructed. And there appears some new domains needed to be studied on thebridge evaluation based on fuzzy analytic hierarchy process, such as consistence check,calculation of best weight and how to decide the recommended interzone values ofdifferent members of different bridges and so on. All these problems give difficulties tothe application of fuzzy analytic hierarchy process to bridge evaluation. So the mainresearches of the thesis are as follows.1. Analytic hierarchy process of bridges is modeled and some calculations areconducted.2. Fuzzy analytic hierarchy process of bridges is modeled calculated.3. The fuzzy analytic hierarchy process on arch bridges is discussed.4. Two in-service old stone arch bridges, Lu Ziwan Bridge and Wu Chaohe Bridge, are healthily evaluated based on fuzzy analytic hierarchy process.