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This work examines the performance of reinforced concrete (RC) beams strengthened using bonded steel wire rope (SWR) at various prestressing levels. The strengthening approach has, however, been applied to the flexural strengthening of RC T-beams in the negative moment region, in order to determine its advantages. For this purpose, four RC T-beams were fabricated and tested under monotonic four-point bending: one control beam (S00), one beam strengthened with non-prestressed SWR (S20), and two beams strengthened with SWR (prestressed at 10% and 20% of their ultimate tensile strength: S21 and S22). The results indicate that the strengthened beams exhibit higher load-carrying capacities. Specifically, the cracking load, yield load, and ultimate load of S20, S21, and S22 increase by 10%–30%, 30%–50%, and 50%–90%, respectively, compared to S00. Additionally, there is an improvement in stiffness and energy absorption capacity. However, these strategies may have a dual effect on the specimens, resulting in a reduction in their ductility index. Finally, the tested beams were replicated using a three-dimensional finite element model, which has proved effective in predicting the behavior of such structures and, therefore, was found to be appropriate for use in future studies. [ABSTRACT FROM AUTHOR]

The old existing reinforced concrete (RC) structures in Taiwan are susceptible to severe damage under earthquakes because of the soft-story mechanism. Moreover, the effects of near-fault ground motions often contain a long period of velocity pulse and permanent ground displacement. This study is based on the tri-axial shaking table test conducted at the National Center for Research on Earthquake Engineering in Taiwan and a series of seismic performance evaluations of a non-ductile RC structure in Taiwan. Finite element analysis (FEA) will be conducted to simulate the linear and nonlinear behavior of the seven-story building. This accommodates the damage plasticity model for concrete and the elastic-perfectly plastic model for reinforcement. Comparison of the results between the experimental test and numerical model showed that the similarity of the vibration period has a great influence on the simulation results. The findings showed that the data of acceleration and displacement behavior corresponded with the experimental results in a satisfactory margin. Also, the damage mode is very similar to the shaking table test results. The study found that using FEA can satisfactorily simulate the seismic performance of mid-rise buildings under a near-fault earthquake. [ABSTRACT FROM AUTHOR]