# Experimental Study on Flexural Capacity of Corroded RC Slabs Reinforced with Basalt Fiber Textile
## 5 Conclusions  
This paper reports the results of an experimental study designed to investigate the feasibility and effectiveness of using externally bonded BFRP and BTRM composites to enhance the flexural performance of RC slabs in different corrosion states. A total of ten slabs were tested under four-point bending until failure. The studied parameters included initial corrosion rate, number of fiber mesh cloth layers, and strengthening materials (BFRP versus BTRM composites). Although the research involved a limited number of specimens, the main conclusion can be drawn as follows.  
1. The corroded RC slabs strengthened by BFRP or BTRM showed better flexural performance when compared with the un-strengthened ones in the serviceability limit state. Compared with the control slabs, the service loads of the strengthened corroded RC slabs improved by 0.41% to 28.05% in the serviceability limit state (\(D_{\text{s}}=l_{0}/200\) mm). Moreover, the service load of BTRM-strengthened slabs increased more significantly than that of BFRP-strengthened slabs, which shows that BTRM composites are more effective in terms of improving the flexural performance of corroded slabs in the serviceability limit state.
2. Both BFRP and BTRM composites can be fully used to improve the flexural capacity of corroded RC slabs in the ultimate limit state. The improvement effect of flexural capacity by BFRP and BTRM composites has a certain relationship with the initial corrosion ratio. The flexural capacities were increased by 27.81%-61.85% under the moderate corrosion condition and 11.52%-33.27% under the severe corrosion condition, respectively. Under the same strengthening condition, the flexural capacities of moderately corroded RC slabs improved more significantly than that of the severely corroded slabs. The flexural capacity improvement also increased with the number of strengthening layers. By increasing the number of textile layers from three to five, the increments of the flexural capacity of the strengthened slabs almost doubled under different corrosion conditions.
3. The experiments showed that both BFRP and BTRM can improve the deformation performance of corroded RC slabs, especially under severe corrosion conditions. Compared with the control slabs, the ductility indexes of strengthened slabs increased slightly under the moderate corrosion condition, even a little lower than that of the control slabs. However, these indexes increased by 18%-35% under the severe corrosion condition. It was observed from the test that all strengthened slabs, except for M-P-5, undergo a long ductile deformation process at the post-peak stage.
4. Based on the damage characteristics of the specimens and the plane section assumption, this study proposed a scheme for calculating the flexural capacity of strengthened corroded RC slabs, which included consideration of the reduction in tensile and bonding performance of corroded steel bars. By comparison, the calculated flexural capacity values of corroded RC slabs strengthened with BFRP and BTRM are in a good agreement with the test results.  
Conceptualization, Y.Z. and W.Y.; Data curation, L.F.; Formal analysis, L.F.; Funding acquisition, Y.Z.; Investigation, L.F. and D.Y.; Methodology, L.F.; Resources, W.Y.; Software, D.Y.; Supervision, Y.Z. and W.Y.; Validation, L.F. and D.Y.; Writing--original draft, L.F.; Writing--review & editing, Y.Z. All authors have read and agreed to the published version of the manuscript.  
This research was funded by National Natural Science Foundation of China: No. 51878264, the Science and Technology Progress and Innovation Project of Department of Transportation of Hunan Province: No. 201912, the Key Research and Development Program of Changsha City: kq1801010.  
Not applicable.  
The data presented in this study are available on request from the corresponding author.