sfrc

FIBER REINFORCED CONCRETE USING LATHE WASTE FOR PAVEMENT 2012-13

CHAPTER-1

INTRODUCTION:

Use of admixtures to concrete has long been practised since BC. In the early 1900s,

asbestos fibres were used in concrete, and in the 1950s the concept of composite materials

came into being and fibre reinforced concrete was one of the topics of interest. There was a

need to find replacement for the asbestos used in concrete. By the 1960s, steel, glass (GFRC)

and synthetic fibres such as polypropylene fibres were used in concrete, and research into

new fibre reinforced concrete continues today. Concrete in general weak in tensile strength

and strong in compressive strength. The main aim of researchers or concrete technologists is

to improve the tensile strength of concrete. To overcome this serious defect partial

incorporation of fibres is practised. Great quantities of steel waste fibers are generated from

industries related to lathes, empty beverage metal cans and soft drink bottle caps. This is an

environmental issue as steel waste fibres are difficult to biodegrade and involves processes

either to recycle or reuse. Fibre reinforced concrete is an interesting topic discussed by

numerous researchers in the last two decades.

Fiber reinforced concrete (FRC) is a composite material consisting of hydraulic

cement, sand, coarse aggregate, water and fibers. In this composite material, short discrete

fibers are randomly distributed throughout the concrete mass. The behavioural efficiency of

this composite material is far superior to that of plain concrete and many other construction

materials of equal cost. Due to this benefit, the use of FRC has steadily increased during the

last two decades and its current field of application includes: airport and highway pavements,

earthquake-resistant and explosive-resistant structures, mine and tunnel linings, bridge deck

overlays, hydraulic structures, rock-slope stabilization.

Extensive research work on FRC has established that addition of various types of

fibers such as steel, glass, synthetic, and carbon in plain concrete improves strength,

toughness, ductility, post-cracking resistance, and etc.

These industrial waste fibers can effectively be used for making high-strength low-

cost FRC after exploring their suitability.

Dept. of highway technology, DSCE


1.1 Objective and scope of present study:Objective of the study is to find out effect of steel fibers in concrete mix

proportion and find out crack reduction of concrete slab with respect to loading.

CHAPTER 2

LITERATURE REVIEW



2.1 General

The year 1824 is a major land mark for the construction industry: that year Aspdin in

England made the formulation for cement. This led to the use of concrete as a construction

material. The first concrete road was probably built in Edinburgh in Scotland, UK, in 1865.

The first concrete road was laid in the USA in Bellefontaine, Ohio, in 1894 by George

Bartholomew, and the pavement's first centennial was celebrated by the American Concrete

Pavement Association. Westergaard's formulae for stresses in concrete slabs (1925) and the

modifications suggested by Teller and Sutherland (1943) are major contributions, which are

the basis of design even now. The standard practice in the early days was to have thickened

edges, and reinforcement was provided to hold together any cracks that form. The proportion

used for the best class of one-course concrete pavement was 1:1.5:2. Transverse joints with

dowels and longitudinal joints were gradually introduced in the 1920s. Thicknesses varied

from 5 in to 10 in (125 to 250mm). Continuously Reinforced Concrete Pavement (CRCP)

started to gain popularity in the mid-1950s, as they eliminated the joints. Fixed form pavers

were introduced in the 1920s. In Europe, the period 1930-40 saw the German Autobahn

system being constructed, with 90 per cent as concrete pavement. By the mid-1960s, edge

thickening design was dropped in the USA. The AASHTO Road Test, conducted between

1958 and 1960, yielded valuable data on the performance of cement concrete pavement,

leading to the now well-known AASHTO designs.

2.2 Evolution of Concrete Pavement technology in India

The cement industry in India is nearly a century old, the first plant having been

commissioned in 1914. Catching up with the world-wide trend then, many concrete roads

were built in 1920s and 1930s. The city roads of Hyderabad (1928), the Marine Drive in

Bombay (1939) and Chandni Chowk in Delhi (1936) were some examples. The Mumbai-

Pune, Mumbai - Nashik and Mumbai - Ratnagiri roads were made of concrete. The slab

thickness adopted was only 100mm, and the concrete mix was 1:2:4. They were laid

manually. The sudden rise in traffic during the Second World War and the increase in the

load carried by trucks caused the slabs to crack after 15-20 years of service. The serious

shortages of cement in the 1940s and 1950s virtually ruled out the construction of any new



concrete roads. After a long gap of nearly three decades, a concrete pavement was

constructed in the 1960s between Agra and Mathura. Serious shortages of cement continued

and no further work was taken up. The partial decontrol of cement in the 1982 gave a boost to

the cement industry and many new plants came up. The existing plants switched over from

the wet process to the dry process. As a result, the installed capacity rose from 28 million

tonnes in 1980 to 140 million tonnes now. Cement is now available and can also be imported.

Taking advantage of the easy availability of cement, the construction of 60 Km (two-lane)

concrete road was taken up between Delhi and Mathura in 1991 and was completed in 1995.

This project may be said to be a trend-setter, since it saw the introduction of new concepts

like the provision of a sub-base of Dry Lean Concrete and a polythene sheet separation layer,

use of slip-form paver, sawn joints, use of polysulphide cold-poured sealant and use of curing

compounds. The road is in a good condition after 12 years of heavy traffic. Other projects

soon followed like the Mumbai - Pune Expressway, the Indore bypass, the Kanpur - Kolkata

highway, certain sections of Kolkata - Chennai highway, and certain sections of Pune -

Bangalore highway. Many roads in cities like Mumbai, Pune, Indore and Nagpur were taken

up as concrete pavement.

2.3 Advantages of Concrete Pavements

a) Long Life

One of the big advantages of cement concrete roads is their long life of about 20-25

years. If the condition of the road is carefully monitored and a concrete overlay is provided

just before the occurrence of extensive cracks, the life can be further extended.

b) Maintenance Free

Unlike a flexible pavement, a cement concrete pavement does not develop potholes

and rutting. Thus, routine repairs such as pot-hole filling and patching which so common in

flexible pavements are not necessary. This saves money, materials and hindrance to traffic.

Apart from such routine maintenance, the surface of a flexible pavement requires a renewal

to improve its riding quality to its original value.

c) Hard and Durable Surface



The concrete pavement maintains a hard durable surface throughout its life. The bump

integrator value of a newly constructed concrete pavement is in the range of 1500-2000

mm/Km, and this value may marginally increase by 500mm/ Km over a period of 20 years.

On the other hand, a flexible pavement loses its riding quality every year by about 500mm.

Thus, after 4-5 years of service, the riding quality of a flexible pavement deteriorates from

1500-2000 mm/Km to begin with to 3500-4500 mm/Km; As a result, a surface renewal

becomes necessary to restore the riding quality to the initial value. Besides, higher values of

riding quality result in extra fuel consumption, extra wear and tear of vehicles and reduced

speed.

d) Better Performance under Heavy Rainfall and Poor Drainage Conditions

A flexible pavement permits water to percolate through its micro-cracks. The ingress

of water causes stripping between aggregates and binder. The ingress of air causes oxidation

of bitumen and loss of its volatiles. Thus, bituminous surfaces develop potholes and loss of

aggregates under heavy rainfall and poor drainage conditions. On the other hand, a good

concrete is dense and virtually waterproof and a concrete pavement performs well under high

rainfall and poor drainage conditions.

e) No Effect of Oil Spillage

Oil drippings from vehicles have no effect on concrete. On the other hand, they

dissolve the bitumen and cause a pitted surface, ultimately leading to loss of binder to hold

the aggregates together. Thus, concrete pavements are ideal for parking areas, toll plazas,

truck lay-byes, petrol stations, bus depots and bus stops.

f) Good Light Reflectivity and Illumination

Concrete being light coloured, reflects light. Hence, the illumination required for a

concrete road is less than that for the dark coloured bituminous surface. For city streets,

consumption of energy is thus reduced.

g) Economics of Concrete Roads

One of the commonly held beliefs is that the initial cost of a cement concrete

pavement is higher than that of a flexible pavement. This argument might have been valid

when bitumen was available at low prices. Since the price of bitumen has increased to a large



extent compared to price of cement, even in initial cost, a properly designed pavement for

highways is 15 percent costlier than a comparable cement concrete pavement. If fly-ash is

used to partially replace cement, the flexible pavement is costlier by nearly 30 percent, even

in initial cost. When whole-life-cycle cost is considered, the cost difference is enormous.

Thus, when whole-life -cycle-costs are considered, a cement concrete pavement always

emerges as the better alternative.

h) Scope for the insertion of secondary reinforcements

The property of concrete to accept the insertion of secondary reinforcements

has led to a humongous scope for innovations and attempts to make concrete stronger and

reduce the surface thickness. Concrete can be reinforced by a various types of Fibers. Major

types of fibers in use are Micro fibers, for example Polypropylene Fibers, Hooked End Steel

Fibers, Lathe Scrap Steel Fibers etc and Macro Fibers which have high aspect ratios. Fibers

prevent concrete from getting cracks due to Shrinkage and other distresses and also increase

the strength and durable characteristics.

2.4 Steel fibers

Steel fibers have been used in concrete since the early 1900s.The early fibers were

round and smooth and the wire was cut or chopped to the required lengths. The use of

straight, smooth fibers has largely disappeared and modern fibers have either rough surfaces,

hooked ends or are crimped or undulated through their length. Modern commercially

available steel fibers are manufactured from drawn steel wire, from slit sheet steel or by the

melt-extraction process which produces fibers that have a crescent-shaped cross section.

Typically steel fibers have equivalent diameters (based on cross sectional area) of from 0, 15

mm to 2 mm and lengths from 7 to75 mm. Aspect ratios generally range from 20 to 100.

Steel fibers have high tensile strength (0, 5 – 2 GPa) and modulus of elasticity (200 GPa), a

ductile/plastic stress-strain characteristic and low creep.

Steel fibers have been used in conventional concrete mixes, shotcrete and slurry-

infiltrated fiber concrete. Typically, content of steel fiber ranges from 0.25% to 2.0% by

volume. Fiber contents in excess of 2% by volume generally result in poor workability and



fiber distribution, but can be used successfully where the paste content of the mix is increased

and the size of coarse aggregate is not larger than about 10 mm.

Concretes containing steel fiber have been shown to have substantially improved

resistance to impact and greater ductility of failure in compression, flexure and torsion.

Similarly, it is reported that the elastic modulus in compression and modulus of rigidity in

torsion are no different before cracking when compared with plain concrete tested under

similar conditions. It has been reported that steel-fiber-reinforced concrete, because of the

improved ductility, could find applications where impact resistance is important. Fatigue

resistance of the concrete is reported to be increased by up to 70%.

2.4.1 Types of Fibers

Two broad types of fibers are in use:

Low modulus fibers, such as nylon, polypropylene and polyethylene etc.

High modulus fibers, such as carbon, glass, asbestos, steel etc.

The use of low modulus fibers, though improving impact resistance of the concrete, does

not result in an appreciable increase in its strength. Of the various high modulus fibers, steel

fibers have been found to be most suitable for use in concrete, from considerations of

providing higher modulus of elasticity, and increased resistance to alkali attack, thermal

shock and fire etc. in addition, they impart better flexural and compressive strengths, abrasion

resistance and impact resistance. The various types of fibers based on the origin are presented

as follows:

Table2.4 Types of Fibers

Fiber origin Types

Steel Fibers Lathe scrap, Crimp/hook-end, straight/deformed slit,

sheet or wires, melt extract, machined chip etc.,

Glass Fibers Strands, ravings, woven or chopped mat strand etc.,

Synthetic Fibers Nylon, polypropylene, polyester, carbon, acrylic,

polyethylene etc.,



Natural fibers Jute, coir ,bamboo, san, hemp, leaf fibers etc.,

Fig 2.4

Jute,

Polypropylene, Glass fibers, Lathe Scrap fibers

Figure 2.4

Manufactured Steel Fibers

2.5 Fiber Reinforced Concrete (FRC)

Fiber reinforced concrete is a concrete composite of cement, fine coarse aggregate

and fibers with different proportions. In plain concrete, micro cracks develop even before



loading, particularly due to drying, shrinkage or other causes of volume change. The width of

these initial cracks seldom exceeds few microns. When loaded, the micro cracks propagate

and open up due to the stress concentration additional cracks form in place of minor defects.

The structural cracks proceed slowly in the matrix and the development of such micro cracks

is the main cause of inelastic deformation the concrete. Normally, water passes through

concrete by way of unwanted cracks and voids that develop during the early stages. Fibers

enable concrete to progress from plastic state to hardened state without weakness. This is

achieved by the reduction of micro cracks formation, reduced segregation and decreasing the

scope of capillary formation, thus reducing permeability. Generally, fibers are chosen

depending upon the aspect ratio. Aspect ratio is defined as length (l) to diameter (d) of the

fiber.

Aspect Ratio= ld

The mechanical and physical properties of fiber reinforced concrete depend upon the

fiber volume, fiber geometry, fiber orientation, mix proportions, size, shape and volume of

coarse aggregate contents and mixing and compaction methods.

Concrete is characterized by brittle failure, the nearly complete loss of loading

capacity, once failure is initiated. This characteristic, which limits the application of the

material, can be overcome by the inclusion of a small amount of short randomly distributed

fibers (steel, glass, synthetic and natural) and can be practiced among others that remedy

weaknesses of concrete, such as low growth resistance, high shrinkage cracking, low

durability, etc. Steel fiber reinforced concrete （SFRC ） has the ability of excellent tensile

strength, flexural strength, shock resistance, fatigue resistance, ductility and crack arrest.

Therefore, it has been applied abroad in various professional fields of construction, irrigation

works and architecture. There are currently 300,000 metric tons of fibers used for concrete

reinforcement. Steel fiber remains the most used fiber of all (50% of total tonnage used)

followed by polypropylene (20%), glass (5%) and other fibers (25%) (Banthia[1], 2012). Steel

fiber reinforced concrete under compression and Stress-strain curve for steel fiber reinforced

concrete in compression was done by Nataraja.C. Dhang, N. and Gupta, A.P [2]. They have



proposed an equation to quantify the effect of fiber on compressive strength of concrete in

terms of fiber reinforcing parameter. Mechanical properties of high-strength steel fiber

reinforced concrete were done by Song P.S. and Hwang S. They have marked brittleness with

low tensile strength and strain capacities of high strength concrete can be overcome by

addition of steel fibers. Tdyhey investigated an experimental study were steel fibers added at

the volume of 0.5%, 1.0%, 1.5% and 2.0%.

The observation indicate that compressive strength of fiber concrete reached a

maximum at 1.5%volume fraction, being 15.3% improvement over the HSC. The split tensile

and Flexural Strength improved 98.3% and 126.6% at 2.0% volume fraction.

2.5.1 Reinforcement Mechanisms in Fiber Reinforced Concrete

In the hardened state, when fibers are properly bonded, they interact with the matrix

at the level of micro-cracks and effectively bridge these cracks thereby providing stress

transfer media that delays their coalescence and unstable growth. If the fiber volume fraction

is sufficiently high, this may result in an increase in the tensile strength of the matrix. Indeed,

for some high volume fraction fiber composite, a notable increase in the tensile/flexural

strength over and above the plain matrix has been reported. Once the tensile capacity of the

composite is reached, and coalescence and conversion of micro-cracks to macro-cracks has

occurred, fibers, depending on their length and bonding characteristics continue to restrain

crack opening and crack growth by effectively bridging across macro-cracks. This post peak

macro-crack bridging is the primary reinforcement mechanisms in majority of commercial

fiber reinforced concrete composites.

2.5.2 Factors Affecting Properties of Fiber Reinforced Concrete

Volume of Fibers

Volume of fibers is an important criterion in FRC. It is the ratio of volume of fiber to

total volume of matrix. Strength of FRC depends on volume of fiber. For economic reasons,

the current practice is to minimize fiber volume. It has been reported that first crack flexural

strength and ultimate flexural strength increase with fiber content. However, as fiber volume

fraction is increased, fibers tend to bundle up and become non-uniformly distributed due to

mixing and placing. Addition of short steel fibers to concrete increases its strength but only

up to some critical amount.



Aspect Ratio

The ratio of Length of a single fiber to its diameter is termed as Aspect Ratio. To

utilize fracture strength of fibers fully, adequate bond between concrete and fibers has to be

developed. This depends on shape and aspect ratio. Fibers with higher aspect ratio are

difficult to mix, resulting in “Balling” of fibers. Fiber aspect ratio of 80-100 has been found

to be optimum for meeting requirements of mixing, placing, compaction and strength

development.

Orientation of Fibers

In conventional reinforcements bars are oriented in the direction desired while in fiber

reinforcement fibers are randomly oriented. Fibers aligned parallel to the applied load offer

more tensile strength and toughness than randomly distributed or perpendicular fibers.

Increase in strength of concrete is inversely proportional to the square root of fibers spacing.

Workability and Compaction

For a given volume of fiber, workability of the mix decreases as the aspect ratio of the

fiber increases. This situation adversely affects consolidation of fresh mix. Even prolonged

external vibration fails to compact the concrete. Fibers interlock and entangle around

aggregate particles considerably reducing workability, while the mix becomes cohesive and

less prone to segregation. The factors having predominant effect on workability are aspect

ratio and fiber volume concentration. Long thin fibers tend to mat together. Short stubby

fibers cannot interlock and can be dispersed by vibration.

Mixing

Mixing of fiber reinforced concrete requires careful conditions to avoid balling of

fibers, segregation and difficulty in mixing the materials uniformly. Increase in aspect ratio,

volume percentage, size and quality of coarse aggregate intensify the balling tendencies.

2.5.3 Effect of Workability on Steel Fibers

Slump tests were carried out to determine the workability and consistency of fresh

concrete. The efficiency of all fiber reinforcement is dependent upon achievement of a

uniform distribution of the fibers in the concrete, their interaction with the cement matrix, and

the ability of the concrete to be successfully cast or sprayed (Brown J. & Atkinson T [3].2012).

Essentially, each individual fiber needs to be coated with cement paste to provide any benefit



in the concrete. Regular users of fiber reinforcement concrete will fully appreciate that adding

more fibers into the concrete, particularly of a very small diameter, results in a greater

negative effect on workability and the necessity for mix design changes. The slump changed

due to the different type of fiber content and form. The reason of lower slump is that adding

steel fibers can form a network structure in concrete, which restrain mixture from segregation

and flow. Due to the high content and large surface area of fibers, fibers are sure to absorb

more cement paste to wrap around and the increase of the viscosity of mixture makes the

slump loss (Chen and Liu[4], 2000).

2.5.4 Effect of Steel Fiber on Compressive, Splitting Tensile and Modulus

of Rupture of Concrete

Presently, a number of laboratory experiments on mechanical properties of SFRC

have been done. Shah Suendra and Rangan[5], in their investigations conducted uni-axial

compression test on fiber reinforced concrete specimens. The results shown the increase in

strength of 6% to 17% compressive strength, 18% to 47% split tensile strength, 22% to 63%

flexural strength and 8% to 25% modulus of elasticity respectively.

Byung Hwan[6] Oh, in their investigations, the mechanical properties of concrete have

been studied, these results shown the increase in strength of 6% to 17% compressive strength,

14% to 49% split tensile strength, 25% to 55% flexural strength and 13% to 27% modulus of

elasticity respectively.

Balaguru P. and Jonh Kendzulak[7](1986), in their paper „Flexural behaviour of steel

fiber reinforced concrete have presented the result of an experimental investigation on the

behavior of fiber concrete beam subjected to static and cyclic flexural loading.,

Barrows and Figueiras[8], in their investigations the mechanical properties of concrete

have been studied, these results shown the increase in strength of 7% to 19% compressive

strength, 19% to 48% split tensile strength, 25% to 65% flexural strength and 7% to 25%

modulus of elasticity respectively.

Chen S[9] investigated the strength of 15 steel fiber reinforced and plain concrete

ground slabs. The slabs were 2x2x0.12m, reinforced with hooked end steel fibers and mill cut

steel fibers.



Dwaraknath and Nagaraj[10] predicted flexural strength of steel fiber concrete by these

parameters such as direct tensile strength, split cylinder strength and cube strength. James

stated that the minimum fiber volume dosage rate for steel, glass and polypropylene fibers in

the concrete matrix is calculated approximately 0.31%, 0.40% and 0.75%.

Patton and Whittaker[11] investigated on steel fiber concrete for dependence of

modulus of elasticity and correlation changes on damage due to load.

Rossi[12] et. Al, analyzed that the effects of steel fibers on the cracking at both local

level (behavior of steel fibers) and global level (behavior of the fiber/cement composite) were

dependent to each other.

Nakagawa H., Akihama S., and Suenaga T[13]. (1989), in their paper entitled

“Mechanical properties of various types of fiber reinforced concrete” have reported the

International Journal of Emerging trends in Engineering and Development ISSN 2249-6149

Issue 2 Vol.2 (March-2012) Page 216 mechanical properties of concrete reinforced with

carbon fiber, Aramid fibers, and high strength Vinylon fibres. The authors have carried out

flexural test using different types of fibers. Ramakrishnaa V., Wu G. Y., and Hosalli G.

(1989), in their paper entitled, Flexural behavior and toughness of fiber reinforced concrete‟

have presented the result of an extensive investigation to determine the behavior and

performance characteristics of the most commonly used fiber reinforced concrete. Hence this

study explores the feasibility of steel fiber reinforcement; aim is to do parametric study on

flexural strength study, with variables of grade of concrete, aspect ratio and percentage of

steel.

Sener[13] et. Al, calibrated the size effect of the 18 concrete beams under four-point

loading. Swami and Saad, have done an investigation on deformation and ultimate strength of

flexural in the reinforced concrete beams under 4 point loading with the usage of steel fibers,

where consists of 15 beams (dimensions of 130x203x2500mm) with same steel

reinforcement (2Y-10 top bar and 2Y-12 bottom bar) and variables of fibers volume fraction

(0%, 0.5% and 1.0%). Tan et al concluded some investigation on the shear behavior of steel

fiber reinforced concrete. 6 simply supported beams were tested under two- point loading

with hooked steel fibers of 30mm long and 0.5mm diameter, as the fiber volume fraction

increased every 0.25% from 0% to 1.0%.



Vandewalle[15], had done a similar crack behavior investigation, which based on

combination of five full scale reinforced concrete beams (350x200x3600mm) with steel

fibers (volume fraction of 0.38% and 0.56%).In this investigation, the experimental results

and theoretical prediction on the crack width was compared.

Pereira et al. had an experimental research on the steel fiber-reinforced self-

compacting concrete and numerical simulation of punching test. Using notched cylindrical

specimens, fracture energy of steel fiber reinforced concrete was measured, and a new

trilinear cohesive law was proposed by Kazemi et al.

By testing the deformational behavior of conventionally reinforced steel fiber

concrete beams in pure bending, Dwarakanath and Nagaraj gave an economical and efficient

use of steel fibers.

The study results given by Thomas and Ramaswamy indicate that the fiber and matrix

interaction contributes significantly to enhancement of mechanical properties caused by the

introduction of fibers.

Numerical analysis and field test on performance of steel fiber reinforced concrete

segment in subway tunnel were described by Zhu. Bending and uni-axial tensile tests on

hybrid fiber reinforced concretes combining fibers with different geometry and material have

been done by Sorelli et al.

2.5.5 Effect of Steel Fiber on Impact Capacity and Toughness of Concrete

Toughness is a measure of the ability of the material to absorb energy during

deformation estimated using the area under the stress-strain curves. Luo et. al, studied and

conducted test on the mechanical properties and resistance against impact on steel fiber

reinforced high-performance concrete. Five different geometry of fibers included steel-sheet-

cut fibers and steel ingot milled fibers with four fiber volume fractions (4%, 6%, 8% and

10%) were applied in to the mix.

Eswari, P. et. al studied and conducted test for fiber content dosage V f ranged from

0.0 to 2.0 percent. Steel and Polyolefin fibers were combined in different proportions and

their impact on strength and toughness studied. Addition of 2.0 percent by volume of hooked-

end steel fibers increases the toughness by about 19.27%, when compared to the plain



concrete. When the fibers were used in a hybrid form, the increase in above study parameters

was about 31.42%, when compared to the plain concrete.

2.5.6 Effect of Steel Fibers on Static Fatigue Characteristics

With the addition of steel fibers, the fatigue life of concrete is said to increase

effectively delaying the failure. Fibers are able to bridge micro-cracks and retard their

growth, thereby enhancing the composite’s performance under cyclic loading. On the other

hand, the presence of fibers increases the pore and initial micro-crack density, resulting in

strength decrease. The overall outcome of these two competing effects depends significantly

on the fiber volume.

Ramakrishnan, et. al. have shown that with a fiber content of 0.5%, the specimen was

able to withstand 2 million repitions at a stress ratio of 100%.

Antonio Nanni made a study of fatigue behavior of steel fiber reinforced concrete and

did a comparison between the lathe scrap (slit-sheet) fibers and hooked end fibers. He found

out that with a very minimal variation, the behavior of concrete under fatigue loading in both

the cases is practically equal.

Sun Wei and Yan Yun of China in 1992 did a detailed study of performance of Steel

Fiber Reinforced Silica Fume Concrete on Fatigue Characteristics. They found that with the

addition of steel fibers and also silica fume concrete, the number of repetitions of load taken

by the specimen was almost infinite or at least more than a million.

N Ganeshan[14] et. al. have found out that the addition of steel fibers in

concrete increase the number of repetitions of load to failure and they tend to make the joints

stronger.

G I Chang et. al. also made fatigue studies on SFRSFC and developed models

based on the results. They came out with the result that the fatigue strength to the first crack,

static flexural strength increases by increasing the fiber content up to 2.0%.

S P Singh and B R Ambedkar et. al. have done a detailed flexural fatigue

studies on Steel Fiber Reinforced Concrete by varying the steel fiber percentage. They have



also done the probability of failure analysis and developed a model based on the results

which shows better performance of FRSFC under fatigue.

The studies emphasize that fiber reinforcement in a cement bound road base has the potential

to improve performance by improving fatigue life of the base and improved resistance to

reflective cracking of the asphalt. The studies also establish that the properties of hardened

SFRCC, such as flexural strength, are remarkably better than those of conventional RCC.

Thus, the use of steel fiber for effective pavement construction can be suggested positively.

Conference on Recent Trends in Engineering & Technology

The specimens added with the waste metals have a significant result over the compressive

strength. The compressive strength for the lathe waste was found to be 21.43% respectively

greater than that of the conventional concrete. G.Murali, C.M.Vivek Vardhan, R.Prabu,

Z.Mohammed Sadaquath Ali Khan, T.Aarif Mohamed, T.Suresh [IJERA][15]

It is possible to make FRC with good strength and with good strength-to-weight by

adding steel lathe waste fibers. In terms of strength, strength-to-weight ratio, it can be used

for construction of structures subjected to seismic, impact, dynamic, etc. loading. Adding of

steel lathes waste fibers in plain concrete enhance its strength under compression. Adding of

steel lathes waste fibers reduces the workability of fresh concrete. By this method. It may be

a good environmental management of lathes steel wastes since a large quantity of steel wastes

are generated from industrial lathes (3-4 kg/lathe. Day). The recycling represents a solution

of that waste and makes use of it. Abbas Hadi Abbas from University of Tikrit-Iraq[16].

The studies also establish that the properties of hardened SFRCC, such as flexural

strength, are remarkably better than those of conventional RCC. Thus, the use of steel fiber

for effective pavement construction can be suggested positively Ravindra V. Solanki Prof. C.

B. Mishra Dr. F. S. Umrigar Prof. D. A. Sinha[17].



CHAPTER-3

METHODOLAGY

Mix design of M30 concrete as per IRC 44:2008

By using lathe waste for reinforcing the concrete.

By achieving the better strength & workability with our test results. as per IRC-

44:2008 the mix design is prepared .For M-30 grade ,the w/c ratio as 1:1.8:2.5.

The ratio of fine aggregates, course aggregates with cement is.

3 specimens with normal concrete and 3 specimens with lathe waste has been casted., As per

mix design the compressive strength is determined for 7 days of curing.

For comparing flexural strength of traditional concrete with lathe waste concrete

reinforcement, beams of dimensions are casted and tested for flexural strength under 2 point

loading after 7 days.

CHAPTER-4

RESULTS AND CONCLUSION



The following table shows the result of 7days curing of concrete cubes

Sl no. Particulars Compressive strength in MPa

1 Normal concrete 9.158.988.72

2 Concrete with steel lathe waste

13.4111.3310.9

Cube 1 Cube 2 Cube 30

2

4

6

8

10

12

14

16

Chart Title

NormalcocreteNormalconcrete+lathe waste steel

The above graphical representation of the compressive strength of normal concrete

and concrete addition with lathe steel scrap. From the graph, it is observed that the addition of

steel fibers in the concrete increases the compressive strength.

The average compressive strength for 7days curing of normal concrete cube:

8.95mpa.The average compressive strength for 7days curing of silica and polypropylene mix

concrete cube: 11.88mpa.

4.1 CONCLUTION



The present study proves the mechanical properties of the concrete are increased. The

above study proves that the additional of scrap steel fiber the compressive strength of the

increases. The cost of the materials used in normal concrete and concrete with lathe waste

steel fiber is not much difference. But using of lathe waste fiber we can achieve longer life

than normal concrete and maintenance cost of concrete pavement cracks maintenance will be

reduced.

Conclusion of case studies are: The study proves that the mechanical properties of the

concrete are increased. Addition of scrap steel fibres to concrete increases the compressive

strength of concrete marginally. The percentage increase in tensile strength of SSFRC is more

as compared to its compressive strength. By the addition of scrap steel fibres, the flexure

strength was found to increase to a great extent. Thus, Scrap steel fibre obtained from lathe

machine industry as a waste can be used in an innovative way in minor amount as an additive

to enhance the properties of concrete. In this way, the scrap steel fibre can be used as a

substitute for factory made steel fibre.

The studies emphasize that fiber reinforcement in a cement bound road base has the

potential to improve performance by improving fatigue life of the base and improved

resistance to reflective cracking of the asphalt. The studies also establish that the properties of

hardened SFRCC, such as flexural strength, are remarkably better than those of conventional

RCC. Thus, the use of steel fiber for effective pavement construction can be suggested

positively.

CHAPTER-5

REFRENCES

1. IRC 44:2008



2. Banthia N Fiber Synergy In High Strength Matrices,” Materials and Structures, Rilem, Vol 37(274), 2004, p 707-716

3. Nataraja M.C., Dhang N. and Gupta A.P, (1998), “Steel fiber reinforced concrete under compression”, The Indian Concrete Journal, 26(3), pp 353-356.

4. Brown J. & Atkinson T.(2012),”Propex Concrete Systems (International), United Kingdom”, proceedings of FIBCON2012, ICI, Nagpur, India, February 13-14.

5. Chen B, Liu J (2000),”Contribution of hybrid fibers on the properties of the control concrete hybrid fibers. Cem. Con. Comp”. 22(4): 343-351.

6. Shah Surendra and Rangan(1994), “Effect of Fiber addition on concrete strength”, Indian Concrete Journal.

7. Byung Hwan Oh(1992), “Flexural Analysis of Reinforced Concrete Beams Containing Steel Fibers”, Journal of Structural Engineering, ASCE, Vol 118, No.10.

8. Balaguru P. and Jonh Kendzulak “Comparative study on Steel fibre reinforced Cum control concrete under flexural and deflection”.

9. Chen S. (2004), “Strength of steel fiber reinforced concrete ground slabs”, structures and Buildings” Issue SB2.

10. Dwarakanath HV, Nagaraj TS.( 1991),” Comparative Study of Predictions of Flexural Strength of Steel Fiber Concrete”, ACI Materials Journal, Vol 88, N0. 73, pp.49-58.

11. Patton ME, Whittaker WL.( 1983) “Effects of fiber Content and Damaging Load on Steel Fiber Reinforced Concrete Stiffness”, ACI Journal, Vol .80, No.1

12. Rossi “Les Betons de Fibers Metalliques” (presses de l’ENPC, paris,1998).13. Ramakrishnan V, Wu G.Y. and Hosalli G, (1989), “Flexural behaviour and toughness

of fibre reinforced” Transportation Research Record, No.1226, pp 69-77.14. Sener S, Begimgil M, Belgin C.( 2002) “Size Effect on Failure of Concrete Beams

with and without Steel Fibers”, Journal of Materials in Civil Engineering, Vol.14, No.5

15. N Ganeshansteel fibre reinforced high performance concrete for sismic resistant structure’ Civil Engineering and construction Review, pp 54-63

16. G.Murali, C.M.Vivek Vardhan, R.Prabu, Z.Mohammed Sadaquath Ali Khan, T.Aarif Mohamed, T.Suresh [IJERA]

17. Abbas Hadi Abbas from University of Tikrit-Iraq18. USE OF STEEL FIBER IN CONCRETE PAVEMENT: A REVIEW Ravindra V.

Solanki Prof. C. B. Mishra Dr. F. S. Umrigar Prof. D. A. Sinha

APENDIX-1

MIX DESIGN

AS per IRC 44-2008



Grade - M30

Type of cement (opc) = 53 grade

Maximum nominal size of aggregates = 20 mm

Minimum cement content = 325kg/m3

Mass cement content = 425 kg/m3

DESIGN COMPRESSIVE STRENGTH OF MIX PROPORTION

f'ck = fck + 1.65*5

=30+1.65*5

=38.25N/mm2

SELECTION OF W/C RATIO

From Table= w/c=0.45

SI No Grade of concrete Approximate water /cement ratio

1 M25 0.502 M30 0.453 M35 0.424 M40 0.385 M50 0.346 M60 0.28

SECTION OF WATER CONTENT

Water content for 20mm aggregates =175.5 w=0.5

Nominal Maximum Size of Aggregate (mm)

Suggestive water cement ( kg)

10 208



20 186*40 165

By interpolating we will get 0.45=175.0-8.75=166.25approximate166kg\m3

CALCULATION OF CEMENT CONTENT

W/c ratio=0.45

Water content=166kg\m3

Cement content =166/0.45=368.8kg\m3

Silica fume @ 8%wt =369-29.5=339.48approximate 340

polypropylene@2%=340-6.8=333.2approximate333

Codebook IS44-2008

Zone -2

Nominal Maximum Size of Aggregates (mm)

Volume of Coarse Aggregate Per Unit Volume of Total Aggregates for Different Zones of Fine Aggregates

Zone IV

Zone III Zone II Zone I

10 0.50 0.48 0.46 0.4420 0.66 0.64 0.62 0.6040 0.75 0.73 0.71 0.69

For 0.62=0.5

For 0.63=0.45

Vol of fine aggregates 1-0.63=0.37

MIX CALCULATION

Vol of concrete=1m3



Vol of cement = (mass of cement)/sp gravity*1/1000

= 369/3.1*1/1000=0.119m3

Vol of water = (mass of water/sp gravity)*1/1000

=166/1*1\1000=0.166m3

Vol of aggregates =1-(0.119+0.166) = 0.715

Mass of C.A=0.715*0.63*2.7*1000=1216.21approximate=1216

Mass of F.A=0.715*0.37*2.6*1000=687.83approximate=688

Cement: F.A: CA: Water 1:1.8: 3.2:.45


sfrc

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