Mechanical Characterisation of Fibre-Reinforced Concrete Using Cyperus Tegetum (Madur Kathi) Natural Fibres

Abstract

Conventional concrete performs well in compression but remains vulnerable to tensile cracking and brittle failure. Discrete fibres can bridge developing cracks and improve the tensile and flexural response of the cementitious matrix. This study experimentally evaluates Cyperus tegetum (locally known as Madur Kathi), a renewable mat-sedge traditionally cultivated in parts of West Bengal, as a natural fibre additive in M25 and M30 concrete. Fibre contents of 0%, 0.5%, 1.0% and 1.5% by weight of cement were investigated. Fresh-concrete workability was assessed by slump testing, while compressive, split tensile and flexural strengths were measured after 7 and 28 days of water curing. The reported results identify 1.0% fibre content as the best-performing dosage among those tested. At this dosage, the thesis reports approximate improvements of 4% in compressive strength, 8% in split tensile strength and 9% in flexural strength relative to the control mix. Slump decreased as fibre content increased, and the 1.5% mixes showed reduced strength, attributed to fibre clustering, entrapped voids and poorer compaction. The findings indicate potential for Cyperus tegetum as a locally available reinforcement additive, while longer-term durability and microstructural validation remain necessary before structural adoption.

Introduction

This study investigates the use of Cyperus tegetum (Madur Kathi) natural fibres as a sustainable additive in concrete to improve its mechanical properties and reduce dependence on conventional synthetic and steel fibres. Although concrete has high compressive strength, its low tensile strength and brittle behaviour can lead to cracking. Natural fibres offer a potential environmentally friendly alternative, particularly because Cyperus tegetum is locally available in parts of West Bengal and has an established tradition of use in mat manufacturing.

The main objectives of the study are to develop fibre-reinforced concrete, evaluate its compressive, split tensile, and flexural strengths, determine the optimum fibre dosage, and examine potential cost variations.

The experimental investigation used Ordinary Portland Cement (OPC) 43 grade, fine and coarse aggregates, water, chemical admixture, and Cyperus tegetum fibres collected from Purba Medinipur, West Bengal. M25 and M30 concrete mixes were prepared with fibre contents of 0%, 0.5%, 1.0%, and 1.5% by weight of cement. The fibres were cleaned, dried, cut into lengths of approximately 2–4 mm, and subjected to surface treatment. Concrete specimens were tested after 7 and 28 days of water curing to determine their mechanical properties and fresh-concrete workability.

The results indicate that increasing fibre content reduces workability. Slump values decreased from 55 mm to 38 mm for M25 concrete and from 49 mm to 35 mm for M30 concrete as the fibre dosage increased from 0% to 1.5%. However, the inclusion of fibres improved compressive and split tensile strength up to an optimum dosage of 1.0%.

At 1.0% fibre content, the 28-day compressive strength reached 33.55 MPa for M25 concrete and 40.28 MPa for M30 concrete, compared with 32.08 MPa and 38.61 MPa, respectively, for the control mixes. Similarly, the 28-day split tensile strength increased to 3.59 MPa for M25 and 3.86 MPa for M30 concrete. At 1.5% fibre content, strength generally declined, suggesting that excessive fibre addition may negatively affect the concrete matrix and fibre distribution.

The flexural strength results are also being investigated to assess the fibres' contribution to bending performance. However, the supplied text does not include the complete flexural strength results for all fibre dosages, so the optimum dosage for flexural strength cannot be confirmed independently from the available data

Conclusion

1) Cyperus tegetum (Madur Kathi) fibres were incorporated into M25 and M30 concrete at 0.5%, 1.0% and 1.5% by cement weight and compared with fibre-free control mixes. 2) The optimum dosage within the tested range was 1.0%. At 28 days, the tabulated results show M25 compressive strength of 33.55 MPa and M30 compressive strength of 40.28 MPa at this dosage. 3) At 1.0% fibre content, split tensile strength reached 3.59 MPa for M25 and 3.86 MPa for M30, while flexural strength reached 5.32 MPa and 6.35 MPa, respectively. 4) Slump decreased as fibre dosage increased. The 1.5% mixes showed lower strength than the 1.0% mixes, plausibly due to fibre balling, void formation and poorer compaction. 5) Locally available Madur Kathi has potential as a sustainable natural fibre additive, but the evidence in this study is limited to short-term laboratory strength and slump testing.

References

[1] Addis, L.B., Sendekie, Z.B. and Satheesh, N. (2022). Degradation kinetics and durability enhancement strategies of cellulosic fibre-reinforced geopolymers and cement composites. Advances in Materials Science and Engineering, 2022, 1981755. [2] Ahmad, J., Burduhos-Nergis, D.D., Arbili, M.M., Alogla, S.M., Majdi, A. and Deifalla, A.F. (2022). A review on failure modes and cracking behaviors of polypropylene fibres reinforced concrete. Buildings, 12(11), 1951. [3] Alberti, M.G., Picazo, Á., Gálvez, J.C. and Enfedaque, A. (2020). New methodological approach towards a complete characterization of structural fibre reinforced concrete by means of mechanical testing procedures. Applied Sciences, 10(14), 4811. [4] Chiadighikaobi, P.C., Adegoke, M.A., Paul, V.J., Saad, L.A. and Obende, B.A. (2023). A review study of the mechanical characteristics of nano concrete reinforced with hybrid fibre. The Open Construction and Building Technology Journal, 17(1). [5] Hosseini, S.B., Gaff, M., Li, H. and Hui, D. (2023). Effect of fibre treatment on physical and mechanical properties of natural fibre-reinforced composites: A review. Reviews on Advanced Materials Science, 62(1), 20230131. [6] Jayaprakash, K., Osama, A., Rajagopal, R., Goyette, B. and Karthikeyan, O.P. (2022). Agriculture waste biomass repurposed into natural fibres: a circular bioeconomy perspective. Bioengineering, 9(7), 296. [7] Mahmood, A. et al. (2021). Geopolymers and fibre-reinforced concrete composites in civil engineering. Polymers, 13(13), 2099. [8] Maiti, S., Islam, M.R., Uddin, M.A., Afroj, S., Eichhorn, S.J. and Karim, N. (2022). Sustainable fibre-reinforced composites: a review. Advanced Sustainable Systems, 6(11), 2200258. [9] Shah, I., Li, J., Yang, S., Zhang, Y. and Anwar, A. (2022). Experimental investigation on the mechanical properties of natural fibre reinforced concrete. Journal of Renewable Materials, 10(5), 1307. [10] Verma, D. and Goh, K.L. (2021). Effect of mercerization/alkali surface treatment of natural fibres and their utilization in polymer composites: Mechanical and morphological studies. Journal of Composites Science, 5(7), 175. [11] Bureau of Indian Standards. (2018). IS 1199 (Part 2): Methods of sampling and analysis of concrete—Tests on fresh concrete. [12] Bureau of Indian Standards. (2019). IS 10262: Concrete mix proportioning—Guidelines. [13] Bureau of Indian Standards. (2021). IS 516 (Part 1/Sec 1): Methods of tests for strength of concrete. [14] Bureau of Indian Standards. (1999). IS 5816: Splitting tensile strength of concrete—Method of test.

Copyright

Copyright © 2026 B. C. Das, Hemant Sood. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.