advertisement

Fiber reinforced concrete (frc)

40 %
60 %
advertisement
Information about Fiber reinforced concrete (frc)
Education

Published on December 11, 2013

Author: ravishekhar123

Source: slideshare.net

Description

concrete,reinforced concrete, frc, fiber in concrete, methods, principle, application
advertisement

Fiber Reinforced Concrete (FRC) Prepared By Ravi Kumar

Contents  Introduction  Benefits of FRC  Toughening Mechanism  Factor affecting the properties of FRC  Comparison of Mix Proportion of FRC and Plain Concrete  Type of fibers  Steel Fiber Reinforced Concrete (SFRC)  Structural behavior & Durability of SFRC  Problems with SFRC  Application Of FRC  Conclusion  References

Introduction to Fiber Reinforced Concrete  Concrete containing a hydraulic cement, water , aggregate, and discontinuous discrete fibers is called fiber reinforced concrete.  Fibers can be in form of steel fiber, natural fiber , synthetic fiber. fiber, glass

Benefits of FRC  Main role of fibers is to bridge the cracks that develop in concrete and increase the ductility of concrete elements.  Improvement on Post-Cracking behavior of concrete  Imparts more resistance to Impact load  controls plastic shrinkage cracking and drying shrinkage cracking  Lowers the permeability of concrete matrix and thus reduce the bleeding of water

Toughening mechanism  Toughness is ability of a material to absorb energy and plastically deform without fracturing.  It can also be defined as resistance to fracture of a material when stressed.

Contd. Reference: Cement & Concrete Institute http://www.cnci.org.za

Contd. Source: P.K. Mehta and P.J.M. Monteiro, Concrete: Microstructure, Properties, and Materials, Third Edition, Fourth Reprint 2011

Factors affecting the Properties of FRC  Volume of fibers  Aspect ratio of fiber  Orientation of fiber  Relative fiber matrix stiffness

Volume of fiber  Low volume fraction (less than 1%) Used in slab and pavement that have large exposed surface leading to high shrinkage cracking  Moderate volume fraction(between 1 and 2 percent) Used in Construction method such as Shortcrete & in Structures which requires improved capacity against delamination, spalling & fatigue  High volume fraction(greater than 2%) Used in making high performance fiber reinforced composites (HPFRC)

Contd. Source: P.K. Mehta and P.J.M. Monteiro, Concrete: Microstructure, Properties, and Materials, Third Edition, Fourth Reprint 2011

Aspect Ratio of fiber  It is defined as ratio of length of fiber to it’s diameter (L/d).  Increase in the aspect ratio upto 75,there is increase in relative strength and toughness.  Beyond 75 of aspect ratio there is decrease in aspect ratio and toughness.

Orientation of fibers  Aligned in the direction of load  Aligned in the direction perpendicular to load  Randomly distribution of fibers It is observed that fibers aligned parallel to applied load offered more tensile strength and toughness than randomly distributed or perpendicular fibers.

Relative fiber matrix  Modulus of elasticity of matrix must be less than of fibers for efficient stress transfer.  Low modulus of fibers imparts more energy absorption while high modulus fibers imparts strength and stiffness.  Low modulus fibers e.g. Nylons and Polypropylene fibers  High modulus fibers e.g. Steel, Glass, and Carbon fibers

Comparison of Mix Proportion between Plain Concrete and Fiber Reinforced Concrete Material Plain concrete Fiber reinforced concrete Cement 446 519 Water (W/C=0.45) 201 234 Fine aggregate 854 761 Coarse aggregate 682 608 -- 157 Fibers (2% by volume) The 14-days flexural strength, 8 Mpa, of the fiber reinforced was about 20% higher than that of plain concrete. Source: Adapted from Hanna, A.N., PCA Report RD 049.01P, Portland cement Association, Skokie, IL, 1977

Types of fiber used in FRC  Steel Fiber Reinforced Concrete  Polypropylene Fiber Reinforced (PFR) concrete  Glass-Fiber Reinforced Concrete  Asbestos fibers  Carbon fibers and Other Natural fibers

Contd. Type of fiber Tensile strength (Mpa) Young’s modulus (x103Mpa) Ultimate elongation (%) Steel 275-2757 200 0.5-35 Polypropylene 551-690 3.45 ~25 Glass 1034-3792 ~69 1.5-3.5 Nylon 758-827 4.14 16-20 Source: ACI Committee 544, Report 544.IR-82, Concr. Int., Vol. 4, No. 5, p. 11, 1982

Steel Fiber Reinforced Concrete  Diameter Varying from 0.3-0.5 mm (IS:280-1976)  Length varying from 35-60 mm  Various shapes of steel fibers

Advantage of Steel fiber  High structural strength  Reduced crack widths and control the crack widths tightly, thus improving durability  less steel reinforcement required  Improve ductility  Reduced crack widths and control the crack widths tightly, thus improving durability  Improve impact– and abrasion–resistance

Structural Behavior of Steel Fiber Reinforced Concrete  Effect on modulus of rupture  Effect of compressive strength  Effect on Compressive strength & tensile Strength at fire condition i.e. at elevated temperature

Effect on Modulus of Rupture Ref: Abid A. Shah, Y. Ribakov, Recent trends in steel fibered high-strength concrete, Elsevier, Materials and Design 32 (2011), pp 4122–4151

Effect on Compressive Strength Ref: Abid A. Shah, Y. Ribakov, Recent trends in steel fibered high-strength concrete, Elsevier, Materials and Design 32 (2011), pp 4122–4151

Structural behavior at Elevated Temperature Ref: K.Srinivasa Rao, S.Rakesh kumar, A.Laxmi Narayana, Comparison of Performance of Standard Concrete and Fibre Reinforced Standard Concrete Exposed To Elevated Temperatures, American Journal of Engineering Research (AJER), e-ISSN: 2320-0847 p-ISSN : 2320-0936, Volume-02, Issue-03, 2013, pp-20-26

Contd. Ref: K.Srinivasa Rao, S.Rakesh kumar, A.Laxmi Narayana, Comparison of Performance of Standard Concrete and Fibre Reinforced Standard Concrete Exposed To Elevated Temperatures, American Journal of Engineering Research (AJER), e-ISSN: 2320-0847 p-ISSN : 2320-0936, Volume-02, Issue-03, 2013, pp-20-26

Durability  Resistance against Sea water (In 3% NaCl by weight of water)  Maximum loss in compressive strength obtained was about 3.84% for non-fibered concrete and 2.53% for fibered concrete  Resistance against acids (containing 1% of sulfuric acid by weight of water)  Maximum loss in compressive strength obtained was found to be about 4.51% for non-fibered concrete and 4.42% for fiber concrete

Problems with Steel Fibers  Reduces the workability;  loss of workability is proportional to volume concentration of fibers in concrete  Higher Aspect Ratio also reduced workability

Application of FRC in India & Abroad  More than 400 tones of Steel Fibers have been used recently in the construction of a road overlay for a project at Mathura (UP).  A 3.9 km long district heating tunnel, caring heating pipelines from a power plant on the island Amager into the center of Copenhagen, is lined with SFC segments without any conventional steel bar reinforcement.  steel fibers are used without rebars to carry flexural loads is a parking garage at Heathrow Airport. It is a structure with 10 cm thick slab.  Precast fiber reinforced concrete manhole covers and frames are being widely used in India.

Conclusion  The total energy absorbed in fiber as measured by the area under the load-deflection curve is at least 10 to 40 times higher for fiber-reinforced concrete than that of plain concrete.  Addition of fiber to conventionally reinforced beams increased the fatigue life and decreased the crack width under fatigue loading.  At elevated temperature SFRC have more strength both in compression and tension.  Cost savings of 10% - 30% over conventional concrete flooring systems.

References  K.Srinivasa Rao, S.Rakesh kumar, A.Laxmi Narayana, Comparison of Performance of Standard Concrete and Fibre Reinforced Standard Concrete Exposed To Elevated Temperatures, American Journal of Engineering Research (AJER), e-ISSN: 2320-0847 p-ISSN : 2320-0936, Volume-02, Issue03, 2013, pp-20-26  Abid A. Shah, Y. Ribakov, Recent trends in steel fibered highstrength concrete, Elsevier, Materials and Design 32 (2011), pp 4122–4151  ACI Committee 544. 1990. State-of-the-Art Report on Fiber Reinforced Concrete.ACI Manual of Concrete Practice, Part 5, American Concrete Institute, Detroit,MI, 22 pp

Contd.  P.K. Mehta and P.J.M. Monteiro, Concrete: Microstructure, Properties, and Materials, Third Edition, Fourth Reprint 2011, pp 502-522  ACI Committee 544, Report 544.IR-82, Concr. Int., Vol. 4, No. 5, p. 11, 1982  Hanna, A.N., PCA Report RD 049.01P, Portland Cement Association, Skokie, IL, 1977  Ezio Cadoni ,Alberto Meda ,Giovanni A. Plizzari, Tensile behaviour of FRC under high strain-rate,RILEM, Materials and Structures (2009) 42:1283–1294  Marco di Prisco, Giovanni Plizzari, Lucie Vandewalle, Fiber Reinforced Concrete: New Design Prespectives, RILEM, Materials and Structures (2009) 42:12611281

Add a comment

Related presentations

Related pages

Fiber Reinforced Concrete (FRC)

Hier sollte eine Beschreibung angezeigt werden, diese Seite lässt dies jedoch nicht zu.
Read more

Fiber-reinforced concrete - Wikipedia

Fiber-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete ...
Read more

Fiber Reinforced Concrete (FRC ) - UW Courses Web...

Concrete Technology Fiber-Reinforced Concrete Professor Kamran M. Nemati Winter Quarter 2015 2 Concrete Technology 3 FRC - Historical Perspective BC horse Hair
Read more

FRC Industries | Concrete Fibers | Steel, Polypropylene ...

As the fastest growing fiber company in the United States, FRC INDUSTRIES strives each and every day to provide you with quality products coupled with ...
Read more

Fiber Reinforced Concrete Association - FRCA

ABOUT THE FIBER REINFORCED CONCRETE ... of knowledge of Fiber Reinforced Concrete (FRC) ... of the most popular fiber reinforcement ...
Read more

Fiber Reinforced Concrete | FRC | Concrete Fibers | Fiber ...

Fiber Reinforced Concrete (FRC) is gaining attention as an effective way to improve the performance of concrete. Fibers are currently being specified in ...
Read more

Fiber-Reinforced Concrete – FRC Mix | CEMEX USA

Fiber-reinforced concrete from CEMEX can be used to improve everything from slabs, driveways, and patios to swimming pools, sidewalks, and decks.
Read more

Fiber Reinforced Concrete (FRC) - Tokyo Institute of ...

Fiber-Reinforced Concrete ATCEATCEATCE-I --I I Advanced Topics in Civil Engineering Professor Kamran M. Nemati First Semester 2006 1 Advanced Topics in ...
Read more

Fiber Reinforced Concrete Association | FRCA is focused on ...

The Fiber Reinforced Concrete Association (FRCA) is focused on the development, knowledge and market of fiber reinforced concrete in the concrete industry.
Read more

Mix Design of Fiber Reinforced Concrete (FRC) Using Slag ...

International Journal of Modern Engineering Research (IJMER) www.ijmer.com Vol. 3, Issue. 6, Nov - Dec. 2013 pp-3863-3871 ISSN: 2249 ...
Read more