Fiber Reinforced concrete (FRC) Fiber Reinforced concrete (FRC)

Fiber-reinforced concrete (FRC) is a type of concrete that contains fibers, typically made of steel, synthetic materials, or natural fibers, to improve its mechanical properties and durability. The fibers are dispersed throughout the concrete mix to create a composite material with enhanced strength, toughness, and resistance to cracking.

Description of FRC:

1. *Improved tensile strength*: Fibers help to absorb stresses and resist cracking, leading to increased tensile strength.
2. *Enhanced durability*: FRC is more resistant to degradation from environmental factors, such as freeze-thaw cycles, chemicals, and abrasion.
3. *Reduced shrinkage*: Fibers help to minimize shrinkage cracks, resulting in a more stable and durable concrete.
4. *Increased impact resistance*: FRC can absorb impact without significant damage, making it suitable for high-traffic areas.
5. *Design flexibility*: FRC can be used in various applications, including slabs, beams, columns, and infrastructure projects.

Common types of fibers used in FRC:

1. *Steel fibers*: Most commonly used, providing high tensile strength and durability.
2. *Synthetic fibers* (e.g., polypropylene, nylon): Offer corrosion resistance and are suitable for applications where steel fibers may not be ideal.
3. *Natural fibers* (e.g., cellulose, bamboo): Biodegradable and sustainable options, often used in specialized applications.

FRC is used in various construction projects, including:

1. Industrial floors and pavements
2. High-rise buildings and infrastructure
3. Bridges and highways
4. Airports and seaports
5. Dams and water treatment plants

By incorporating fibers into the concrete mix, FRC offers improved performance, durability, and sustainability, making it a popular choice for demanding construction projects.

1. A PROJECT REPORT ON STRENGTH ANALYSIS OF FIBRE REINFORCED CONCRETE A Project report submitted in partial of the requirement for the award of the degree of BACHELOR OF TECHNOLOGY IN CIVIL ENGINEERING Submitted By M. DEVA REDDY 20BK5A0134 MD. ASIF 20BK5A0137 V. SAI THILAK 20BK5A0154 Under the esteemed guidance of MR. RAVI KUMAR (ASST PROF)

2. ABSTRACT The usefulness of strength analysis of fibre reinforced concrete (FRC) in various civil engineering applications is indisputable. Fiber reinforced concrete has so far been successfully used in slabs on grade, architectural panels, precast products, offshore structures, structures in seismic regions, thin and thick repairs, crash barriers, footings, hydraulic structures and many other applications. Fiber Reinforced Concrete (FRC) is gaining attention as an effective way to improve the performance of concrete. Fibers are currently being specified in tunneling, bridge decks, pavements, loading docks, thin unbonded overlays, concrete pads, and concrete slabs. These applications of fiber reinforced concrete are becoming increasingly popular and are exhibiting excellent performance Fiber-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete fibers that are uniformly distributed and randomly oriented. Fibers include steel fibers, glass fibers, synthetic fibers and natural fibers This study presents understanding Strength of fiber reinforced concrete Mechanical properties and durability of fiber reinforced concrete. KEYWORDS: Steel Fiber Reinforced Concrete, tensile strength, compressive strength

3. INTRODUCTION Composite material consisting of mixtures of cement, mortar or concrete and discontinuous, discrete, uniformly dispersed suitable fibers. Fiber-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity Fiber-reinforced normal concrete are mostly used for on-ground floors and pavements but can be considered for a wide range of construction parts (beams, pliers, foundations ). Fibers include steel fibres , glass fibres , synthetic fibres and natural fibres . Within these different fibers that character of fiber reinforced concrete changes with varying concretes, fibre materials, geometries, distribution, orientation and densities. Addition of fiber reinforcement in discrete form improves many engineering properties of concrete.

4. TYPES OF FIBERS ➤ Steel Fibres • Aspect ratios of 20 to 100. • Diameters vary from 0.25 mm to 0.75 mm. • High structural strength. • Used in precast and structural applications, highway and airport pavements, refractory and canal linings, industrial flooring, bridge decks, etc. ➤ Glass Fibres • High tensile strength, 1020 to 4080 N/mm². Generally, Fibres of length 10 mm to 50mmare used. • Increased flexural strength, ductility and resistance to thermal shock. • Used in building renovation works, ducts and roofs, sewer lining, ridge and tunnel liningpanels , Acoustic barriers and screens etc.

5. Synthetic Fibres Man-made Fibres from petrochemical and textile industries. High chemical resistance. Low modulus of elasticity. Cheap, abundantly available. Applications in cladding panels and shotcrete. Polymers fibres Fibre forming polymers are linear macromolecules that are usually suitable for making man-made fibres. The term "synthetic fibre will be used to denote all man-made fibres manufactured from non cellulosic raw materials. Synthetic fibres are the result of extensive research by scientists to improve on naturally occurring animal and plant fibres

6. REVIEW OF LITERATURE Dharani. N et al. (2013) The optimal replacement percentage of cement with hypo sludge is found to be 30% when Recron 3s fibers are not added. On addition of Recron 3s fiber with cement matrix, the compressive strength and split tensile strength decrease with increase in fiber content, however the flexural strength increases with increase in fiber content. When hypo sludge and Recron 3s fiber are added, the optimum dosage of Hypo sludge is 20% and optimum Fiber content is 0.4%. Usage of Recron 35 fibers will reduce the segregation, cost of maintenance by reducing the micro cracks and permeability and hence the durability will increase.

7. Mr. R. Balamurugan, et.al (2014) The compressive strength increased up to 10% addition of hypo sludge and further increase in hypo sludge reduces the strengths gradually. If silica is added the strength will be considerably increased, because of lack of silica in hypo sludge. considerably this type of Concrete, will be used for road works effectively with less consumption of cement. Dharani .N (2015) 10% replacement of cement with Hypo sludge and 50% replacement of fine aggregate with Copper slag show increase in compressive strength and flexural strength compared to other combinations, 10% replacement of cement with Hypo sludge and 40% replacement of fine aggregate with Copper slag show increase in split tensile strength compared to conventional mix. With increase in curing days 30% replacement of cement with hypo sludge shows decrease in split tensile strength when compared to other combinations .

8. Nilesh K. Vasoya ., et al (2015) The industrial waste materials were found to be performing better than normal concrete, in properties such as workability, durability, permeability and compressive strength. Utilization of these wastes in concrete will not only provide economy but also help in reducing disposal problems. S. C. Patodi , C. V. Kulkarni (2012) The authors found that matrix having 0.3% of recron and 0.7% of steel fiber volume fraction was found: More balanced in terms of strength and post-peak ductility. Best resistance against impact and maximum toughness. For overall better performance. Advantages in improving concrete properties . Zoran J. Grdic et al. (2012) Abrasive resistance of concrete is reduced with the increase of water/cement ratio from 0.5 to 0.7 which is reflected in the increase of the value of abrasion resistance rate.

9. RESEARCH GAP research gaps that shouldbe addressed in future studies... the compression in concrete and tension in steel fibers are developed fiber reinforced concrete. measuring thevelocity and attenuation of an ultrasonic wave travellingthrough concrete. two slabs, since the maximum travel time for the two slabs However, the study of hydration and shrinkage ofconcrete inside the CFRP detect gaps in CFRPreinforced concrete structures and CFFTs. The detectionof such small gaps is ....

10. OBJECTIVE The main objective is to study the behavior of reinforced concrete beams strengthened with steel fiber. To study the effect of steel fiber strengthening of RC Beams on ultimate bad carrying capacity and failure pattern. Comparative study of the crack pattem and crushing behavior between controlled beam and strengthened FRC beams

11. The fineness of cement is a measure of cement particle size and is denoted in terms of the specific surface area of cement.  The Fineness Test of Cement is done by sieving cement samples through a standard IS sieve. The weight of a cement particle whose size is greater than 90 microns is determined.   Fineness of Cement RESULTS : Percentage of residue 8.5%

12. Compressive Strength of Cement The compressive strength of cement gives the idea about the basic cement strength. It gives the assurance for using. From this test, you can find how much cement is required and how much strength it will get.  RESULTS

13. The Initial setting time of cement is the time when the cement paste starts losing its plasticity and final setting time of cement is the time when the cement paste completely loses its plasticity. Setting time is essential that cement set neither too rapidly nor too slowly. For OPC, usually the value of initial setting time is 30 minutes and final setting time is 10 hours. Test to Determine the Setting Time of Cement RESULTS : Initial setting time 30 minutes Final settin time 10 hours

14. Tests on aggregate Crushing test . Concept and significance of the Aggregate crushing value test. The 'aggregate crushing value test ` gives a relative measure of the resistance of an aggregate to crushing under a gradually applied compressive load. Aggregate crushing value is defined as the percentage by weight of the crushed (or finer) material obtained when the test aggregates are subjected to a specified load under standardized conditions, and the strength of the aggregate used in road construction is expressed by numerical index. RESULTS : crushing value of aggregate 23.38%

15. Abrasion test Abrasion testing determines the relative quality, toughness, and durability of mineral aggregates subjected to impact and abrasion. Values derived from both the Micro Deval and the L.A. Abrasion tests offer information about the performance of aggregate in use RESULTS : Aggregate abrasion value 40.5%

16. 1. Compressive strength :   TESTING OF SPECIMENS :

17. Testing of hardened concrete is important for controlling the quality of concrete. The main purpose of testing hardened concrete is to conform that the concrete has developed required strength. The compressive strength is one of the most important properties of hardened concrete and in general it is the characteristic value for classification of concrete in various codes. Compression test of cubes is the most common test conducted on hardened concrete because it is an easy test to perform and most of the desirable properties ofconcrete are comparatively related to its compressive strength. The compression test was carried on cubical specimen of size 150mm x 150mm x 150mm in a compression testing machine of capacity 2000KN, at a loading rate of 14N/mm 2 . The test was done for determining the 3 rd , 7 th and 28 th day compressive strength.

18. 2. Split tensile strength :

19. The split tensile strength test is a well-known indirect test used for determining the tensile strength of concrete. Test was carried out on concrete cylinder of size 150mm x 300mm. In split tensile strength test, Concrete cylinder was placed with its axis horizontal, between the loading surface of a compression testing machine and the load was applied until failure occurred due to a splitting in the plane, containing the vertical diameter of the specimen. In order to reduce the magnitude of high compression stress near the points of application of the load, narrow packing strips of plywood were placed between the specimen and loading plates of the testing machine. The split tensile strength was determined after 28day water curing.

20. 3. Modulus of elasticity :

21. The modulus of elasticity was determined by subjecting cylinder specimen having 150mm diameter and 300 mm height to uniaxial compression. The corresponding deformation by means of compressometer has been taken at each increment of loads. The gauge length of compressometer is 20 cm. Dial gauge of compressometer gives the deformation under each increment of loading. Dial gauge reading is divided by gauge length will give the strain and load applied divided by area of cross section gives the stresses. A series of reading were taken and the stress-strain graphs were plotted. From the stress-strain graph, the modulus of elasticity was obtained as the slope of the graph. The modulus of elasticity was determined after 28 day water curing.

22. Specimens 3 rd day compressive strength (N/mm 2 ) 7 th day compressive strength (N/mm 2 ) 28 th day compressive strength (N/mm 2 ) HFRC- S100C0 28.80 33.20 53.33 HFRC- S75C25 12.56 20.22 35.56 HFRC- S50C50 27.60 32.24 52.22 HFRC- S25C75 26.54 31.33 49.27 HFRC- S0C100 25.12 31.30 49.26 cube compressive strength for HFRC specimens :

23. Cube compressive strength variation of HFRC

24. REFERENCE : R.N. Swamy, “Testing and Test methods of Fiber Cement Composites”, Published1978, (pp 42-43). Surendra P. Shah , James I. Daniel, Darmawan Ludirdja , “Toughness of Glass Fiberreinforced concrete panels subjected to accelerated aging”, PCI Journal, September- October 1987, (pp 83-88). Arnon Bentur and Sidney mindess , “ Fiber reinforced cementetious composites” ,Second edition 2007, chapter 8 Amit rana “ some studies on steel fibre reinforced concrete” , Vol 3,2013

25. Abdul Ghaffar, Amit S.Chavan , Dr.R.S . Tatwawadi , “ Steel Fibre Reinforced Concrete “,International Journal of Engineering Trends and Technology (IJETT). Alan J,Bookes , “ Cladding of Buildings”, Third Edition published 2002. K. Dharunsankar (2016) An Experimental Study on Concrete with hybrid Fibers. ASCE, 02(10), 103-110. IS 516-1959. “Method of Test of Strength of Concrete”, BIS. Narayanan, R. and Darwish, I. Y. S. “Use of Steel fibers as shear Reinforcement”, ACI structural Journal. Vol. 84, No. 3. Zoran J. Gradic (2012) “Abrasion resistance of concrete micro-reinforced with polypropylene fibers”.

26. Grija.S , Shanthini.D , Abinaya.S (December 2016) : “A Review On Fiber Reinforced Concrete” S. Sharmila and Dr. G.S. Thirugnanam (2013): “Behavior of Reinforced Concrete Flexural Member with Hybrid Fibre under Cyclic Loading.” D. Maruthachalam , B. G. Vishnuram , K. Gurunathan and I. P admanaban (May- 2011): “Durability properties of fibrillated polypropylene fibre reinforced high performance concrete.” J.D.Chaitanya kumar , G.V.S. Abhilash, P.Khasim Khan, G.Manikanta sai , V.Taraka ram (2016): “Experimental Studies on Glass Fiber Concrete.” Ms. K.Ramadevi , Ms. R. Manju (2012): “Experimental Investigation on the Properties of Concrete with Plastic PET (Bottle) Fibres as Fine Aggregates.”

27. CONCLUSION : A brief state-of-the-art report on fiber reinforced concrete is presented.Our understanding of fiber-matrix interaction, reinforcement mechanisms and performance characteristics is fairly advanced. Fiber reinforced concrete is a promising material to be used in the Middle-East for sustainable and long- lasting concrete structures. Its performance has already been proven in other hot and arid climates and in other chemically deleterious environments. Fiber reinforced concrete pavements prove to be more efficient than conventional RC pavements, in several aspect Compressive strength for fibre reinforced concrete is seen to be improved. It can be clearly seen that strength at 28 days for CSFRC 1% is better than other cases hence recommended.

28. RESULT : For the hybrid combination of 50% steel fibre and 50% carbon fibre , the split tensile decreased when compared to SFRC mix for 28 days. Thus tensile strength decreased with addition of hybrid fibre . The modulus of elasticity for steel fibre volume fraction of 0.25%, 0.50%, 0.75% and 1.00% were 30.12 N/mm 2 , 31.43 N/mm 2 , 32.56 N/mm2, and 35.59 N/mm 2 respectively. Thus 1.00% of steel fibre gave high modulus of elasticity for 28 days. The hybrid combination of steel and carbon fibre is tested for modulus of elasticity for 28 days.