Structural performance assessment of deteriorated prestressed concrete beams

초록

This study experimentally and analytically evaluated the structural performance of prestressed concrete (PSC) beams deteriorated by aging and other factors. A PSC beam specimen was designed and fabricated, with accelerated corrosion applied to the prestressing (PS) steel strands under tension at the bottom of the beam. Using the Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST) computer program, the PS steel element was modified to simulate the interaction between concrete and PS steel in deteriorated PSC members. The damage modeling considered the reduction in the crosssectional area of the PS steel, loss of bond strength, reduction in the ductility of the PS steel, and deterioration of concrete strength. The experiment and analysis results revealed a nonlinear correlation between the maximum load and corrosion level. The deterioration model accurately predicted the performance degradation of the structure. Moreover, the 0.05 coefficient of variation of the experiment/analysis values for ultimate load in the tested deteriorated PSC beam specimens indicated that the behavioral characteristics of PSC beams according to different corrosion levels were well represented. This study facilitated deformation, cracking, and damage predictions of deteriorated PSC structures under various loading scenarios based on the level of corrosion exposure, PS level, and localized corrosion in PSC beams. The findings of this study emphasize the significance of bonded PS steel deterioration, such as corrosion, addressing the research gap regarding the detrimental effects of corrosion on structural performance.

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