MARIO ADRIEL VAZQUEZ PELAEZ

Seismic retrofit of steel truss bridge using CFRP sheet （鋼トラス橋のCFRPシートによる耐震補強）

Takeshi MIYASHITA

This research has the purpose of proving if CFRP sheets can be used as reinforcement material under a compressive load and get data on the effect of CFRP sheets when used as reinforcement material. Load Bearing Capacity Test is done on 13 specimens with an H-Shaped cross-section that is divided into series b, a, c, and d. Series b is one specimen without reinforcement to be compared with others for having a bigger plate thickness in flanges and web. The three remaining series are divided into four cases. Case with specimens with no reinforcement. Case 1: Specimens reinforced with CFRP sheets in the vertical direction. Case 2: Specimens reinforced with CFRP sheets in the vertical and horizontal direction. Case 3: Like Case 2, but the CFRP sheets in the horizontal direction are reduced. Additionally, FEM analysis is done to make the fundamental research for future designs related to this member and CFRP sheets reinforcements. Case 1 proves to increase buckling load and toughness. However, overall stiffness loss after web buckling is not improved. In Case 2, buckling load increases further. Flanges reinforcement increases toughness further, and stiffness reduction due to local buckling on the web is improved. Case 3, compared to case 2, the buckling load in the web, stiffness, and toughness barely change, and the buckling load on the flanges increases. For future research, experiments reducing CFRP sheets in both directions will be done. FEM models have the effect of initial deflection according to Japan's Road Bridge Specifications. Results regarding maximum load and buckling load were similar, however, the results regarding the behavior of stiffness and toughness were different. For future research, the welding effect in the specimen should be considered. Adding the effect of residual stress could make the results closer to the real ones.