| Summary: | 碩士 === 國立臺灣大學 === 土木工程學研究所 === 87 === In this study , we aimed at the flexure ductility and shear capacity for hollow circular reinforced concrete bridge column .First , we reviewed some studies on the confinement effects and shear capacity evaluate code, and we do some analysis about the topic purpose we concerned . Reduced scale model tests were proceeded to compare with the theoretical prediction , and verify if the analyses were applicable or not.
By the way of changing the height-depth ratio(type L:4.63 , type M: 2.78 , type S:2.22)to induce different failure mode , we manufactured three column types ( type L 250cm , type M 150cm , type S 120cm) with the same outer diameter 54cm and inside diameter 27cm . The confinement arrangement we used have longitudinal bars and circular hoops on both outer and inner side , furthermore , between outer and inner longitudinal bars steel ties were configured . Horizontal force was applied by reciprocate cyclic load , and on the top of column constant axial force about 0.8 was applied to simulate the dead weight of the upper structure.
Applying the stress-strain model for confined concrete which Hoshikuma & Kawashima announced in 1998 and basic mechanics hypotheses, we edit an program to evaluate the moment-curvature relation curve. Refer to several suggested code for estimating the shear capacity to evaluate the curve for shear-ductility relationship.
According to the result of test, hollow circular bridge column’s ductility can reach about 5 to 6, and the flexure moment-curvature analysis by use of Hoshikuma & Kawashima model can make a good prediction.
Finally, we exam the codes suggested for shear capacity, we find out that the code suggested by Priestly, Verma & Xiao is most reliable.
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