# Mechanical Strength Characterization of Plastic Fiber Reinforced Cement Concrete Composites
## 5 Conclusions  
The following conclusions were arrived at based on the experimental observations obtained from this study. Shredded plastic waste fibers obtained from domestic waste plastic bottles were used in the production of two different types of concrete systems:(i) homogenously distributed in entire volume of concrete sections, and (ii) plastic fibers confined in the tension zone of concrete beam sections. Experimental tests were conducted on these concrete systems in compression and flexural bending and the test observations are summarized below:  
1. Stress-strain characteristics of fiber incorporated concretes up to 0.15% \(\mathrm{V_{f}}\) in compression were appreciably improved with a higher compressive strength of 33.20 \(\mathrm{N/mm^{2}}\) and post-peak compressive toughness of 357.75 N-m.
2. Maximum absolute toughness of 516.38 N-m was reported in the case of plastic fiber substituted concrete mixes (PFC-10H) with a toughness increase up to 321%.
3. Compressive failure modes were typically controlled with visible multiple cracks on the surface. Post-peak toughness of concrete showed controlled deformation without sudden failure due to composite ductility of plastic fibers in the matrix.
4. Flexural evaluations of plastic fiber incorporated concrete mixes placed either homogenously or tension zone confined concretes were beneficial in improving the bending properties of concrete. However, the effective fibers placed in the tension zone appreciably contributed to the overall increase in the flexural parameters. Plastic fiber incorporation at 0.15% \(\mathrm{V_{f}}\) in concrete mixes resulted in maximum flexural toughness of 33.43 N-m and maximum residual strength of 4.37 \(\mathrm{N/mm^{2}}\).
5. All the flexural test properties were consistently increased when the total fiber volume was confined in the tension zone due to the effective load sharing capability of fibers as well as the maximum fiber availability. Plastic fibers control the sudden growth of cracking inside the matrix before reaching the ultimate load, thereby exhibiting an improved post-crack toughness.  
* The optimal plastic fiber volume (0.10% V\({}_{\text{f}}\)) is promising in contributing to the fiber reinforcing efficiency in the matrix and crack bridging mechanism, providing maximum stress carrying capacity. Maximum flexural strength (5.26 N/mm\({}^{2}\)) and post peak drop load resistance (96%) were obtained in the tension zone confined concrete compared to full depth homogenous fiber reinforced concretes.  
Conceptualization, S.A. and M.A.; Methodology, S.A. and M.A.; Investigation, S.A. and M.A.; Writing--original draft, S.A. and M.A.; Writing--review & editing, S.A. and M.A.; Funding acquisition, S.A. and M.A. Both authors have read and agreed to the published version of the manuscript.  
This research was funded by the Deanship of Research, King Khalid University, Grant no.12 and the APC was funded from the research grant.  
Experimental datas are presented clearly in the graphical format and Tables in the manuscript as well as the procedure for test measurements and calculation is presented clearly for each test methods.  
The authors gratefully acknowledge the Deanship of Research, King Khalid University for providing financial support for this sponsored research project.  
The authors declare no conflict of interest.