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The capability of durable structure to resist weathering action, chemical attack, abrasion and other degradation processes during its service life with the minimal maintenance is equally important as the capacity of a structure to resist the loads applied on it. Although concrete offers many advantages regarding mechanical characteristics and economic aspects of the construction, the brittle behavior of the material remains a larger handicap for the seismic and other applications where flexible behaviour is essentially required.
LOGIN CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) About Us (/about-us.html) Subscription (/subscription/levels.html) (/component/banners/click/225.html) Advertise with us (/advertise-with-us.html) E-Newsletter (/e-newsletter.html) (/component/banners/click/220.html) Polypropylene Fiber Reinforced Concrete : An Overview The capability of durable structure to resist weathering action, chemical attack, abrasion and other degradation processes during its service life with the minimal maintenance is equally important as the capacity of a structure to resist the loads applied on it Although concrete offers many advantages regarding mechanical characteristics and economic aspects of the construction, the brittle behavior of the material remains a larger handicap for the seismic and other applications where ퟢ�exible behaviour is essentially required Recently, however the development of polypropylene 韛�ber-reinforced concrete (PFRC) has provided a technical basis for improving these de韛�ciencies This paper presents an overview of the effect of polypropylene (PP) 韛�bers on various properties of concrete in fresh and hardened state such as compressive strength, tensile strength, ퟢ�exural strength, workability, bond strength, fracture properties, creep strain, impact and chloride penetration The role of 韛�bers in crack prevention has also been discussed S K Singh, Scientist, Structural Engineering Division, Central Building Research Institute, Roorkee & Honorary Secretary Institute of Engineers, Roorkee Introduction Ceramics were the 韛�rst engineering materials known to mankind and they still constitute the most used materials in terms of weight [1, 2] Hydraulic cements and cement-based composites including concretes are the main ceramic-based materials Concrete offers many advantages in the application due to its improved mechanical characteristics, low permeability and higher resistance against chemical and mechanical attacks Although concrete behavior is governed signi韛�cantly by its compressive strength, the tensile strength is important with respect to the appearance and durability of concrete The tensile strength of concrete is relatively much lower Therefore, 韛�bers are generally introduced to enhance its ퟢ�exural tensile strength, crack arresting system and post cracking ductile behaviour of basic matrix (/component/banners/click /229.html) Concrete modi韛�cation by using polymeric materials has been studied for the past four decades [3] In general, the reinforcement of brittle building materials with 韛�bers has been known from ancient period such as putting straw into the mud for housing walls or reinforcing mortar using animal hair etc Many materials like jute, bamboo, coconut, rice husk, cane bagasse, and sawdust as well as synthetic materials such as polyvinyl alcohol, polypropylene (PP), polyethylene, polyamides etc have also been used for reinforcing the concrete [4,5,6,7,8] Research and development into new 韛�ber reinforced concrete is going on today as well Polypropylene 韛�bers were 韛�rst suggested as an admixture to concrete in 1965 for the construction of blast resistant buildings for the US Corps of Engineers The 韛�ber has subsequently been improved further and at present it is used either as short discontinuous 韛�brillated material for production of 韛�ber reinforced concrete or a continuous mat for production of thin sheet components Since then the use of these 韛�bers has increased tremendously in construction of structures because addition of 韛�bers in concrete improves the toughness, ퟢ�exural strength, tensile strength and impact strength as well as failure mode of concrete Polypropylene twine is cheap, abundantly available, and like all manmade 韛�bers of a consistent quality Properties of Polypropylene Fibers The raw material of polypropylene is derived from monomeric C3H6 which is purely hydrocarbon Its mode of polymerization, its high molecular weight and the way it is processed into 韛�bers combine to give polypropylene 韛�bers very useful properties as explained below [9]: There is a sterically regular atomic arrangement in the polymer molecule and high crystallinity Due to regular structure, it is known as isotactic polypropylene Chemical inertness makes the 韛�bers resistant to most chemicals Any chemical that will not attack the concrete constituents will have no effect on the 韛�ber either On contact with more aggressive chemicals, the concrete will always deteriorate 韛�rst The hydrophobic surface not being wet by cement paste helps to prevent chopped 韛�bers from balling effect during mixing like other 韛�bers The water demand is nil for polypropylene 韛�bers The orientation leaves the 韛�lm weak in the lateral direction which facilitates 韛�brillations The cement matrix can therefore penetrate in the mesh structure between the individual 韛�brils and create a mechanical bond between matrix and 韛�ber (/component/banners/click /236.html) The 韛�bers are manufactured either by the pulling wire procedure with circular cross section or by extruding the plastic 韛�lm with rectangular cross-section They appear either as 韛�brillated bundles, mono 韛�lament or micro韛�laments as shown in Fig & The properties of these three types of PP 韛�bers are given in Table [10] The 韛�brillated polypropylene 韛�bers are formed by expansion of a plastic 韛�lm, which is separated into strips and then slit The 韛�ber bundles are Figure 1: mono韛�lament 韛�ber Figure 2: Fibrillated 韛�ber cut into speci韛�ed lengths and 韛�brillated In mono韛�lament 韛�bers, the addition of buttons at the ends of the 韛�ber increases the pull out load Further, the maximum load and stress transfer could also be achieved by twisting 韛�bers [11] Role of Fibers Cracks play an important role as they change concrete structures into permeable elements and consequently with a high risk of corrosion Cracks not only reduce the quality of concrete and make it aesthetically unacceptable but also make structures out of service If these cracks not exceed a certain width, they are neither harmful to a structure nor to its serviceability Therefore, it is important to reduce the crack width and this can be achieved by adding polypropylene 韛�bers to concrete [13] The bridging of cracks by the addition of PP 韛�bers has been shown in Fig (/component/banners/click /14.html) Thus addition of 韛�bers in cement concrete matrix bridges these cracks and restrains them from further opening In order to achieve LOGIN more deퟢ�ection in the beam, additional forces and energies are required to pull out or fracture the 韛�bres This process, apart from preserving the integrity of concrete, improves the load-carrying capacity of structural member beyond cracking This improvement CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) creates a long post-peak descending portion in the load deퟢ�ection curve as shown in Fig [12] Reinforcing steel bars in concrete have the same bene韛�cial because they actSubscription as long continuous 韛�bres Short discontinuous 韛�bres have advantage, however, of being About effect Us (/about-us.html) (/subscription/levels.html) Advertise with us the (/advertise-with-us.html) E-Newsletter (/e-newsletter.html) uniformly mixed and dispersed throughout the concrete The major reasons for crack formation are Plastic shrinkage, Plastic settlement, Freeze thaw damage, Fire damage etc Plastic shrinkage: It occurs when surface water evaporates before the bleed water reaches the surface Polypropylene 韛�bers reduce the plastic shrinkage crack area due to their ퟢ�exibility and ability to conform to form The addition of 0.1% by volume of 韛�bers is found effective in reducing the extent of cracking by a factor of 5-10 The extent of crack reduction is proportional to the 韛�ber content in the concrete Table 1: Properties of various types of polypropylene 韛�bers Length Diameter (mm) (mm) Tensile strength (MPa) Modulus of elasticity (GPa) mono韛�lament 30-50 0.30-0.35 547-658 3.50-7.50 91 0.9 micro韛�lament 12-20 0.05-0.20 330-414 3.70-5.50 225 0.91 Currently Online 500-750 5.00-10.00 58 0.95 We have 2142 guests and no members online Fiber type Fibrillated 19-40 0.20-0.30 Figure 3: Bridging of crack using Polypropylene 韛�bers Speci韛�c surface (m2/kg) Density (kg/cm3) Figure 4: Typical load-elongation response in tension of FRC Plastic settlement: High rate of bleeding and settlement combined with restraint to settlement (e.g by reinforcing bars) leads to settlement cracking In case of PFRC, 韛�bers are uniformly distributed Fibers are ퟢ�exible so they cause negligible restraint to settlement of aggregates Freeze thaw damage: Small addition of polypropylene 韛�bers in concrete reduces the ퟢ�ow of water through the concrete matrix by preventing the transmission of water through the normal modes of ingress, e.g capillaries, pore structure, etc The implications of these qualities in concrete with polypropylene 韛�ber additions are that cement hydration will be improved, separation of aggregate will be reduced and the ퟢ�ow of water through concrete that causes deterioration from freeze/ thaw action and rebar corrosion will be reduced, creating an environment in which enhanced durability may take place Spalling of homogenous structure of Concrete due to insuퟵ�cient capillary pores Developed explosion channels due to melting of PP 韛�bers Figure 5: Flowing out of steam pressure through the melted PP 韛�bers in the case of 韛�re Fire damage: Heat penetrates the concrete resulting in desorption of moisture in outer layer Moisture vapors ퟢ�ow back towards the cold interior and are reabsorbed into voids Water and vapor accumulate in the interior thereby increasing the vapor pressure rapidly causing cracks and spalling in the concrete In case of PFRC, the 韛�bers melt at 160oC creating voids in the concrete The vapor pressure is released in newly formed voids and explosive spalling is signi韛�cantly reduced as shown in 韛�g 5[14] Properties of PP Fiber Reinforced Concrete Before mixing the concrete, the 韛�ber length, amount and design mix variables are adjusted to prevent the 韛�bers from balling Good FRC mixes usually contain a high mortar volume as compared to conventional concrete mixes The aspect ratio for the 韛�bers are usually restricted between 100 and 200 since 韛�bers which are too long tend to "ball" in the mix and create workability problems As a rule, 韛�bers are generally randomly distributed in the concrete; however, placing of concrete should be in such a manner that the 韛�bers become aligned in the direction of applied stress which will result in even greater tensile and ퟢ�exural strengths There should be suퟵ�cient compaction so that the fresh concrete ퟢ�ows satisfactorily and the PP 韛�bers are uniformly dispersed in the mixture The 韛�bers should not ퟢ�oat to the surface nor sink to the bottom in the fresh concrete Chemical admixtures are added to 韛�ber-reinforced concrete mixes primarily to increase the workability of the mix Air-entraining agents and water-reducing admixtu- res are usually added to mixes with a 韛�ne aggregate content of 50% or more Superplasticizers, when added to 韛�ber-reinforced concrete, can lower water: cement ratios, and improve the strength, volumetric stability and handling characteristics of the wet mix The properties of PFRC with various 韛�ber volume % are shown in Table Table Mechanical Properties of Polypropylene Fiber Reinforced Concrete No Concrete mix Vf % Fibers fcu ft fs Slump Ref (MPa) (MPa) (MPa) (mm) w/c LOGIN Cement CA (kg/m3) FA (kg/m3) (kg/m3) Admixture Specimen Type shape Super l/d Cylinder, Fibrillated 17.2 1.08 4.5 0.10 100 – (20mm long & 69 14.1 1.72 2.5 [15] 0.30 120 Prism 0.29mm dia) 12.6 1.34 3.0 Subscription (/subscription/levels.html) Advertise 1000 CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) 0.49 390 (OPC) 640 plasticizer Cubes & (10mm) (Fosroc 430) About Us (/about-us.html) 0.45 360 (OPC) 0.45 360 (OPC) 0.48 418 (OPC) 0.40 0.50 0.44 0.39 0.30 10 0.30 11 0.36 12 0.40 1100 (20mm) 1100 (20mm) 724 (25mm) 372 OPC + 1140 28 SF (20mm) 383 1162 (PPC) (20mm) 430 1154 (PPC) (20mm) 498 1136 (PPC) (20mm) 567 (OPC) 567 (OPC) 415 - Prism 647 - Prism (19mm long & 396 0.048mm dia) Mono 韛�lament (30mm long & - Cylinder 750 Superplasticizer Prism 572 - 540 - Mono 韛�lament 0.082 0.128 1.0 55 0.55 mm dia) 998 0.045 1.2 1.4 56 1.0 1.5 Mono 韛�lament 200 0.5 Cylinder, Cubes & Graded Fibrillated Prism (12mm ~ 24mm) Cylinder, Cubes & Graded Fibrillated Prism 12mm ~ 24mm) NIL Superplasticizer 2.24 4.01 2.33 3.76 2.40 2.43 4.01 4.22 2.50 5.36 - 2.68 5.47 - 2.70 5.51 35.03 2.23 35.42 3.21 56.10 4.10 56.10 4.40 5.23 5.47 4.88 5.65 4.95 6.35 41.22 3.72 5.35 46.15 3.89 1120 (20mm) 740 Super plasticizer - (6 mm long & 100 0.25 630 713 Cylinder 81.60 4.40 Fibrillated(30mm Superplasticizer 0.25 71.90 5.40 1050 Cylinder long& 0.06mm 500 (Paric FP300U) 0.50 59.40 4.70 di) (20mm) 5.99 6.12 6.29 5.56 Graded 0.1 50.67 4.88 5.70 Cubes & Fibrillated NR 0.2 55.33 5.09 40 Prism 12mm ~ 24mm) 0.3 57.11 5.52 6.84 Fibrillated 0.06 mm dia) Cylinder, Cubes & Prism Cubes & Cylinder - 0.50 - 60.80 4.10 60.00 4.30 Fibrillated 126 38.20 - 4.80 - 5.10 5.40 38.0 4.00 0.1 34.5 4.40 0.2 42.0 5.00 0.3 41.4 5.15 0.10 Mono 韛�lament 700 37.60 0.10 Mesh Type 150 37.20 - E-Newsletter (/e-newsletter.html) [10] - [10] 38 [16] 4.42 1050 (Paric FP300U) 5.21 5.61 3.54 0.1 49.78 4.53 NR 0.2 50.22 4.67 0.3 52.00 4.75 with us (/advertise-with-us.html) 102 30.74 3.21 35.23 0.1 39.50 NR 0.2 41.00 0.3 48.00 Cylinder, 503 630 314OPC+56 1268 Fly ash Micro 韛�lament 647 100 [29] 80 [25] [25] -400600 400600 73 55 45 [25] [23] [23] [30] 20 20 15 [28] 10 Where: Vf - volume fraction of 韛�ber; fcu - compressive strength; ft - tensile strength and fs - ퟢ�exural strength, SF- Silica fume Polypropylene 韛�bers are used in two different ways to reinforce cementitious matrices One application is in thin sheet components in which polypropylene provides the primary reinforcement Its volume content is relatively high exceeding 5%, in order to obtain both strengthening and toughening In other application the volume content of the polypropylene is low, less than 0.3% by volume, and it is intended to act mainly as secondary reinforcement for crack control, but not for structural load bearing applications [11] The performance and inퟢ�uence of the polypropylene 韛�bers in the fresh and hardened concrete is different and therefore these two topics are treated separately Effects on Fresh Concrete The main parameter, which is often used to determine the workability of fresh concrete, is the slump test The slump value depends mainly on the water absorption and porosity of the aggregates, water content in the mixture, amount of the aggregate and 韛�ne material in the mixture, shape of the aggregates and surface characteristics of the constituents in the mixture The slump values decrease signi韛�cantly with the addition of polypropylene 韛�bers as shown in Table The concrete mixture becomes rather clingy resulting in increasing of the adhesion and cohesiveness of fresh concrete During mixing the movement of aggregates shears the 韛�brillated 韛�bers apart, so that they open into a network of linked 韛�ber 韛�laments and individual 韛�bers These 韛�bers anchor mechanically to the cement paste because of their large speci韛�c surface area The concrete mixture with polypropylene 韛�bers results in the fewer rate of bleeding and segregation as compared to plain concrete This is because the 韛�bers hold the concrete together and thus slow down the settlement of aggregates Due to its high tensile and pull-out strength, the PP 韛�bers even reduce the early plastic shrinkage cracking by enhancing the tensile capacity of fresh concrete to resist the tensile stresses caused by the typical volume changes The 韛�bers also distribute these tensile stresses more evenly throughout the concrete As the plastic shrinkage cracking decreases, the number of cracks in the concrete under loading is reduced, due to decrease in cracks from the existing shrinkage cracks If shrinkage cracks are still formed, the 韛�bers bridge these cracks, reducing at the same time their length and width Moreover, as the rate of bleeding decreases, the use of polypropylene 韛�bers may accelerate the time to initial and 韛�nal set of the concrete as this led to a slower rate of drying in the concrete [14] Table 3: Effect of polypropylene 韛�bers on concrete slump [18] (mm) Initial slump (mm) Final slump (mm) Fiber length (mm) 90 130 170 127 1245 114 76 70 120 48 53 64 51 51 30 51 51 19 Effects on Hardened Concrete The addition of polypropylene 韛�bres in the concrete did not signi韛�cantly affect the compressive strength and the modulus of elasticity but they increase the tensile strength Splitting tensile strength of PFRC approx ranges from 9% to 13% of its compressive strength Addition of PP 韛�bers in concrete increases the splitting tensile strength by approx 20% to 50% [16] Compressive strength: The compression strength of concrete is a vital parameter as it decides the other parameters like tension, ퟢ�exure etc The effect of polypropylene 韛�ber on the compressive strength of concrete has been discussed in many literatures and observed that LOGIN polypropylene 韛�ber either decreases or increases the compressive strength of concrete, but overall effect is negligible in many cases In fact, the effect of a low volume of polypropylene 韛�ber on the compressive strength of concrete may be concealed by the experimental CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) error LOGIN CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) error About Us (/about-us.html) Subscription (/subscription/levels.html) Advertise with us (/advertise-with-us.html) E-Newsletter (/e-newsletter.html) Flexural tensile strength: The ퟢ�exural tensile strength increases with increase in volume fraction of 韛�ber It is also observed that there was increase in strength for with the increase in aspect ratio of 韛�bre Bond strength: It is necessary that there should be a good bond between the 韛�ber and the matrix If the critical 韛�ber volume for strengthening has been reached then it is possible to achieve multiple cracking This is a desirable situation because it changes a basically brittle material with a single fracture surface to fracture into a pseudo ductile material which can absorb transient minor overload and shocks with little visible damage So the aim is to produce large number of multiple cracks at as close spacing as possible so that the crack widths are very small, almost invisible to naked eye so that the rate at which aggressive materials can penetrate the matrix is reduced High bond strength helps to give close crack spacing but it is also essential that the 韛�bers should give suퟵ�cient ductility to absorb impacts But in terms of physiochemical adhesion there is no bond between the 韛�ber and the cement gel The use of chopped and twisted 韛�brillated polypropylene 韛�bers with their open structure has partially remedied the lack of interfacial adhesion by making use of wedge action at the slightly open 韛�ber ends and also by mechanical bonding through 韛�brillation The general pull out loads of twisted 韛�brillated 韛�bers [20, 21] may range from 300-500N for commonly used staples but the accurate calculation of bond strength is complicated by a lack of knowledge of the surface area of 韛�ber in contact with the paste It is observed that in damaged products and in broken specimens, usually 韛�ber breaks instead of 韛�ber pull out [9] Figure 6: Fracture shape of plain concrete Figure 7: Fracture shape of PFR concrete Fracture Properties: The failure behaviour of high-strength concretes is effectively improved by the use of 韛�bers The typical shear bond rupture due to strain localization could be avoided (韛�g 6) Instead of this, a large number of the longitudinal cracking, which was predominantly oriented in the direction parallel or sub-parallel to the external compressive stresses, was formed at the entire concrete specimens as shown in 韛�g7 Creep and shrinkage properties of concrete: Fibers reduce creep strain, which is de韛�ned as the time-dependent deformation of concrete under a constant stress Compressive creep values, however, may be only 10 to 20% of those for normal concrete Shrinkage of concrete, which is caused by the withdrawal of water from concrete during drying, is also reduced by 韛�bers The shrinkage, creep and total time dependent deformation of various PFRC mixes along with non 韛�brous concrete mix are presented in 韛�g 8[15] The reduction in shrinkage due to the presence of 韛�bers is expected from number of viewpoints First, the 韛�bers not exhibit any shrinkage, thus reducing overall shrinkage of the mix In addition the 韛�bers have a role in retaining the water in the concrete mix upto a certain limit which helps to delay the shrinkage Therefore addition of 韛�bers to the concrete mixes is always advantageous in reducing shrinkage deformation Figure 8: Time dependent deformation of polypropylene 韛�bers Figure10: Effect of polypropylene 韛�bers on impact resistance of concrete Flexural impact properties: The number of blows required to develop the 韛�rst visible crack on the beam’s lower surface is de韛�ned as the initial-crack impact number (Ncr) Failure impact number Nf is de韛�ned as the number at which one main macro-crack develops from bottom to top of the beam Impact ductility index is de韛�ned as the ratio of failure impact number to initial crack impact number, which can be used to present the ퟢ�exural impact ductility J=Nf / Ncr where J is impact ductility index, which for plain concrete is The ퟢ�exural impact test results are shown in table by researcher[10] The impact resistance for concretes with various volume fractions of 韛�brillated polypropylene 韛�bers has been shown in 韛�gure 10 The results indicate that signi韛�cant improvement in impact resistance of concrete can be achieved with relatively low volume fraction of polypropylene 韛�bers Table 6: Impact properties of 韛�ber reinforced concrete Type of mix Vf % Average Impact number Average failure Impact number Impact ductility index Control 25.8 26.8 1.04 34.7 28.6 38.1 46.5 30.4 40.1 1.34 1.06 1.05 68.9 70.7 62.8 224.2 712.7 831 3.26 10.08 13.23 0.05 Micro韛�lament 0.095 0.14 Mono韛�lament LOGIN 1.2 1.4 Chloride penetration: Besides improved mechanical properties due to inclusion of 韛�ber, chloride penetration is also reduced CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) substantially by the presence of 韛�bers depending upon its orientation Antoni [17] studied the effect of chloride penetration and found that the effectAbout is insigni韛�cant for shorter 韛�ber due to the(/subscription/levels.html) random orientation of short 韛�bers as compare to long 韛�bers Further, the E-Newsletter (/e-newsletter.html) Us (/about-us.html) Subscription Advertise with us (/advertise-with-us.html) chloride movement into concrete is reduced signi韛�cantly by the presence of 韛�ber as the interfacial transition zone in the direction perpendicular to the chloride penetration whereas 韛�ber provides easier path for the chloride to migrate in direction along the 韛�ber Obstacles in Use of PFRC Although PP 韛�bers are gaining wide applications in many 韛�elds, there is still need for improvement in some properties A major 韛�re will leave the concrete with additional porosity equal to the volume of 韛�bers incorporated in the concrete usually in the order of 0.3 to 1.5% by volumetric fraction In respect of mono韛�lament 韛�bers, the poor bond between 韛�ber and matrix results in a low pull out strength The PP 韛�bers are also attacked by sunlight and oxygen, however surrounding concrete in PFRC protects the 韛�bers so well that this shortcoming is not signi韛�cant Further, sometimes the 韛�bers function as initiator of the micro cracking because of their low modulus of elasticity as compared to the cement matrix Thus mechanical bond with the cement matrix is also low The 韛�bers cause the enhancement of the pores volume of concrete by creating more micro-defects in the cement matrix Conclusion Innovations in engineering design and construction, which often call for new building materials, have made polypropylene 韛�berreinforced concrete applications In the past several years, an increasing number of constructions have been taken place with concrete containing polypropylene 韛�bres such as foundation piles, prestressed piles, piers, highways, industrial ퟢ�oors, bridge decks, facing panels, ퟢ�otation units for walkways, heavyweight coatings for underwater pipe etc This has also been used for controlling shrinkage & temperature cracking Due to enhance performances and effective cost-bene韛�t ratio, the use of polypropylene 韛�bers is often recommended for concrete structures recently PFRC is easy to place, compact, 韛�nish, pump and it reduces the rebound effect in sprayed concrete applications by increasing cohesiveness of wet concrete Being wholly synthetic there is no corrosion risk PFRC shows improved impact resistance as compared to conventionally reinforced brittle concrete The use of PFRC provides a safer working environment and improves abrasion resistance in concrete ퟢ�oors by controlling the bleeding while the concrete is in plastic stage The possibility of increased tensile strength and impact resistance offers potential reductions in the weight and thickness of structural components and should also reduce the damage resulting from shipping and handling Acknowledgment The author wishes to express his sincere thanks to Ms Sonal Dhanvijay & Ms Vedanti Ganwir of Visvesvaraya National Institute of Technology, Nagpur for their valuable help in preparing this paper References Saenz, A., Rivera, E., Brostow, W and Castan˜o, V.M., "J Mater," (Ed.), Vol 21, No.267 (1999) Castan˜o, V M and Rodriguez, J R., "Performance of Plastics" Ch 24, Brostow, W., ed., Hanser, Munich-Cincinnati (2000) Dodson, V., "Concrete and Mixtures" Van Nostrand Reinhold: Structural Engineering Series, New York (1989) Sheldon, R R.,"Composite Polymer Materials" Applied Science Publishers, London (1982) Ramaswamy, H S., Ahuja, B M and Krishnamoorthy, S., "J Mex Inst Cement Concrete" Vol 22,No 161 (1984) Ramaswamy, H S., Ahuja, B M and Krishnamoorthy, S., "J Mex Inst Cement Concrete" Vol 22,No 161 (1984) Jindal, C V., " J Composite Materials," Vol.20, No.265 (1986) Beaudoin, J J., "Handbook of Fibre Reinforced Concrete" Noyes Publications, New Jersey (1990) Colling, J., " J Mex Inst Cement Concrete" Vol 19, No 127 (1981) Hananth, D J., "Fiber Cements and Fiber Concretes" A Wiley-Inter science Publication, John Wiley and Sons, Ltd pp 81-98 Deng, Z., and Li, J., "Tension and Impact Behaviours of New Type Fibre Reinforced Concrete." 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Sukontasukkul, P., "Toughness Valuation of Steel and Polypropylene Fibre Reinforced Concrete Beams under Bending" Thammasat Int J Sc Tech., Vol 9, No 3, (2004),pp.35-41 Ritchie, A.G.B and Mackintosh, D.M., "Selection and Rheological Characteristics of PP 韛�bers," Concrete, pp 36-39 (1972) Hughes, B.P and Fattuhi, N.I., "Fibrer Reinforced Concrete in Direct Tension," Fiber Reinforced Materials, paper 16, conference at Institution of Civil Engineers, London 1977, pp 127-133 Hadi, M N S., "An Investigation of the Behaviour of Steel and Polypropylene Fibre Reinforced Concrete Slabs," 7th International Conference Concrete: Construction’s Sustainable Option - Harnessing Fibres for Concrete Construction, Dundee, Scotland, 8-10 July 2008 Suhaendi, S L., "Residual Strength and Permeability of Hybrid Fiber Reinforced High Strength Concrete Exposed to High Temperature" Part of Ph D Thesis LOGIN Alidoust, O., Sadrinejad, I and Ahmadi, M A., "A Study on Cement-Based Composite Containing Polypropylene Fibers and Finely Ground Glass Exposed to Elevated Temperatures." Procedings of World Academy of Science, Engineering and Technology Vol 23 CREATE AN ACCOUNT (/component/compro韛�ler/registers.html) Suji, D., Natesan, S C., Murugesan, R., "Experimental study on behaviors of polypropylene 韛�brous concrete beams" Journal of About UsSCIENCE (/about-us.html) Subscription (/subscription/levels.html) Advertise with us (/advertise-with-us.html) E-Newsletter (/e-newsletter.html) Zhejiang University A pp 1862-1775 Carnio, M A., Gomes, A E and Lintz, R C C., "Fiber reinforced Concrete" Technical Report on Average Residual Strength (ARS), ASTM C 1399-7a Wang Y., Victor C Li., Backer S., "Tensile Properties of Synthetic Fiber Reinforced Mortar," Cement and Concrete Composites Vol.12 (1990) pp 29-40 Singh S.K.et.al "Internal Report on Steel Free Deck Slab",SERC, Ghaziabad (2000) Shiv Kumar, A & Sathanam,M "Machanical Properties of High Strength Concrete Reinforced with Metallic and Non Metallic Fibres",Cement & Concrete Composites, Vol.27(2007),pp.603-608 Xing, L.B.;Xiang C.M.; Farg C & Luping L "The Mechanical Properties of Polyproplene Fiber Reinforced Concrete", Journal of Wahan University of Technology, Material Science ED.,Vol.19, No.3 (2004), pp.68-71 NBMCW December 2011 (/component/banners/click/249.html) (/component/banners/click/239.html) Publications NBM&CW MGS Architecture L&ST New Building Material & Construction World Modern Green Structures & Architecture Lifting & Specialized Transport View Online Download View Online (http://www.nbmcw.com/Online_Edition/NBMCW/May2017/index.htm) (http://www.nbmcw.com/index.php? option=com_ars&view=download&id=243) Previous Issues (http://www.nbmcw.com/index.php? option=com_content&view=article&id=34157&Itemid=174) Subscribe Now (http://www.nbmcw.com/subscription/levels.html) View Online (http://www.mgsarchitecture.in/Online_Edition/MGS/April2017/index.htm) Download II&TW Indian Infrastructure & Tenders Week (http://www.nbmcw.com/index.php? option=com_ars&view=download&id=242) Previous Issues (http://www.nbmcw.com/index.php? option=com_content&view=article&id=34202&Itemid=175) Subscribe Now (http://www.nbmcw.com/subscription/levels.html) (http://www.nbmcw.com/Online_Edition/Pullout/January2017/index.htm) Download (http://www.nbmcw.com/index.php? option=com_ars&view=download&id=233) Previous Issues (http://www.nbmcw.com/index.php? option=com_content&view=article&id=34228&Itemid=177) Subscribe Now (http://www.nbmcw.com/subscription/levels.html) View Online Download (http://www.nbmcw.com/index.php? option=com_ars&view=download&id=241) Previous Issues (http://www.nbmcw.com/index.php? option=com_content&view=article&id=6455&Itemid=176) Subscribe Now (http://www.nbmcw.com/subscription/levels.html) ... 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