鋼鐵橋樑檢測與修護方法選擇之研究

Abstract

鋼鐵橋樑因其材料之力學特性較混凝土優越，在現代交通建設中扮演重要 的角色。鋼橋在使用年限中，常因意外事故、駕駛人操作不當、自然腐蝕 而造成損壞。然在國內混凝土橋樑研究者不乏其人，而鋼橋則少有研究者 。因此，本研究以鋼橋為主題，將研究範圍限制在「上部結構」，探討適 用於鋼橋的檢測方法、常見的損壞現象、各種常用的修護方法，研究可能 影響鋼橋修護方法選擇之因素、建立修護方法選擇之層級架構，使用「分 析階層程序法」決定各評估準則之權重，再運用「質化與量化多評估準則 」建立評估模式，以求出最佳之修護方法。本研究中舉出FHWA常用的檢測 技術，並將適用於鋼橋之非破壞性檢測技術作更進一步的比較分析。對鋼 橋常發生的損壞現象歸納分析其發生原因，並對各種檢測週期與桿件重要 性、損壞現象列表分析。至於鋼橋常用的修護方法計有：直化法、焊接法 、螺栓法、部份更換、完全更換、組合修護等。但是橋樑修護時考慮重點 為安全、經濟與社會成本。因而將修護方法選擇的層級架構分為非使用者 觀點、使用者觀點、修護特性、工程經濟四個標的，而在其下之準則有： 美觀程度、週邊衝擊程度、交通維持、修護延時、修護耐久性、修護後之 強度、修護後之韌性、修護成本、橋樑剩餘壽命。再利用AHP 與「質化與 量化多評估準則」結合為本研究之評估模式，最後進行例證研究以說明本 研究之評估模式。 Steel bridges play an important part in modern traffic construction because their mechanical characteristics of material are superior to those of concrete ones. Steel bridges are often damaged within the valid years in use due to traffic accident, unsuitable driving skill, and natural erosion. I explore the effective methods of inspecting steel bridge prevalent damage condition, and various methods of rehabilita- tion. Besides, I study the factors that will influence the choice of rehabilitation methods employed in steel bridges. I also establish the hierarchy framework of choosing rehabilita- tion method. On the other hand, I adopt "Analytic Hierarchy Process (AHP)" to decide the weight of various criteria of evaluation; then I use "Multicriteria Evaluation with Qualita- tive and Quantitative to build the evaluating model. By doing these we can try to acquire the best method of rehabilitation. However, the emphases of rehabilitating steel bridges are put on safety, economics, and the society cost. Thus, the hierarchy framework of affecting the choice rehabilitation method is divided into four goals: the view of non-user, the view of user, the attribute of repairs, and the engineering economics. The goals are on the basis of 9 criteria. Next, I combine AHP and "Multicriteria Evaluation with Qualitative and Quantitative Data" as the evaluation model of my research. Finally, I do an assumed case study to demonstrate the evalua- tion model.