PSI - Issue 64

Ali Alraie et al. / Procedia Structural Integrity 64 (2024) 1943–1950 Ali Alraie, Saverio Spadea, Vasant Matsagar/ Structural Integrity Procedia 00 (2019) 000–000

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failure of the beam. Three identical specimens were tested for each of the post-tensioned beam and the control beam. The experimental setup for the bending test on the jute-post-tensioned beams, as well as a tested beam sample, are shown in Fig. 4(a). The failure of the beams was initiated by the yielding of the steel reinforcement, which is evident from the large deflection observed. The extremely low elastic modulus of the NJF rope has saved it from rupture thanks to strain compatibility within the cross-section. The average load-deflection response of the jute-post-tensioned beams compared to the non-post-tensioned beam (control beam) is shown in Fig. 4(b). It can be seen from Fig. 4(b) that the control beam has achieved an average load-carrying capacity of 64.7 kN. In contrast, the post-tensioned beam has achieved an average load-carrying capacity of 67.5 kN with a 4.3% improvement over the non-post-tensioned beam, which agrees with the 4.8% improvement obtained from the analytical investigation. This improvement in load carrying capacity is achieved using one jute rope, as mentioned previously, due to laboratory equipment limitations. However, it can be estimated from these experimental findings that using four NJF ropes may result in a 17.2% improvement in load-carrying capacity, which compares well with the analytical findings (18.6%) and FE analysis (14.3%). Hence, the experimental findings testify to this research's proposed theme and prove post-tensioning efficiency with NJF ropes.

(b)

(a) Fig. 4. (a) Experimental setup and elevational view of the jute-post-tensioned beam tested in bending; (b) Average load-deflection response of the jute-post-tensioned beam compared to the non-post-tensioned beam (control beam). 3. Conclusions This study investigated the sustainability of structures by exploring the possibility and efficacy of strengthening RC beams using natural jute fibre ropes. The conclusions withdrawn from this study are as follows. 1. The load-carrying capacity of the beam post-tensioned with four unbonded NJF ropes is improved by 18.6%, obtained from the analytical investigation, and by 14.3%, from the finite element analysis. 2. The beam's deflection at service load is reduced by 45% while post-tensioning with four unbonded NJF ropes. 3. The experimental tests on post-tensioned beams with one NJF rope have resulted in a 4.3% improvement in the load-carrying capacity compared to the non-post-tensioned beam. Based on this, the improvement in load-