Proposal Correction

8/2/2019 Proposal Correction

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UNDERGRADUATE RESEARCH 2012 PG 04 GRUOP

FACULTY OF ENGINEERING, GALLE Page 1

CHAPTER 01

1.0 INTRODUCTION

Concrete is the most frequently used construction material in the world. However, it has low

tensile strength, low ductility, and low energy absorption. Therefore improving concretetoughness and reducing the size and amount of defects in concrete would lead to better

concrete performance. An effective way to enhance the mechanical properties of concrete is

by adding a small fraction of short fibers to the concrete mix during mixing.

After extensive studies it is widely reported that such fiber reinforcement can significantly

improve the tensile properties of concrete.

Another application of fiber reinforcement is for the reduction of the shrinkage and shrinkage

cracking of concrete associated with hardening and curing. Plastic shrinkage cracks occur in

fresh, unhardened concrete when the rate of evaporation at the concrete surface is greater

than the rate of water migration to the surface.

Because of the strength and stiffness of fresh concrete is very low, only a small amount of

fibers are needed to effectively reduce the plastic shrinkage. Low volume fractions of

synthetic fibers, e.g., 0.1% of polypropylene fibers, are often used to reduce plastic shrinkage

cracking in concrete.

Other benefits of FRC include improved fatigue strength, wear resistance, and durability.

By using FRC instead of conventional concrete, section thickness can be reduced and

cracking can be effectively controlled, resulting in lighter structures with a longer life

expectancy.

FRC is currently being used in many applications, including buildings, highway overlays,

bridges, and airport runways (ACI 1982; Keer 1984; Bentur and Mindess 1990). In load

bearing applications it is generally used along with traditional steel reinforcement (ACI 1988).

In building construction it has become a more common practice to use low-dosage synthetic

fiber reinforcement for floor slabs.

Fibers for concrete generally need to be durable in the cementations environment, be easily

dispersed in concrete mix, have good mechanical properties, and be of appropriate

geometric configuration in order to be effective.

Many fibers have been used for concrete and some are widely available for commercial

applications. They include steel, glass, natural cellulose, carbon, nylon, and polypropylene,

among others.


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Concrete with aggregate from recycled materials, which enables saving sources of natural

aggregate, is considered to have generally worse mechanical properties than common

concrete. But the idea to add fibers to a concrete mixture with aggregate may change

material properties of such concrete, improve behavior and bring about new types of

applications. Concrete with recycled short fibers can be considered as optimal structural

concrete for various applications as mentioned above.

Certain quantity of fibers can be beneficial for enhancing the properties of plain concrete. But

it is not necessary that all properties will be improved, the addition of fibers may increase

certain properties and at the same time may decrease other ones. Therefore the fibers in

appropriate quantity should be selected.

To investigate the effects of fiber quantity on mechanical properties of fiber reinforced

concrete, an experimental program is planned.

This paper reviews some of the work on concrete using recycled fibers, including coconut

coir, PET bottles and steel.

Waste PET bottles had been reworked for drinking bottles by melting fusion, which turned

out to be too costly. Therefore waste PET bottles will be insured to recycling as short fibers

to reduce the rework cost. If waste PET bottles will be reused as short fibers for concrete,

positive effects are expected on the recycling of waste resources and the protection of

environmental containment.

According to official website of International Year for Natural Fibers 2009, approximately, 500000 tons of coconut fibers are produced annually worldwide, mainly in India and Sri Lanka.

Its total value is estimated at $100 million.

Fiber dimensions of the various individual cells are said to be dependent on the type of

species, location and maturity of the plant. The flexibility and rupture of the fiber is affected

by the length to diameter ratio of the fiber and this also determines the product that can be

made from it.


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OBJECTIVES

The main purpose of the research is to study the effect of recycled short fibers to enhance

the mechanical properties of concrete.

The specific aims of the research are:

To study the effect of fiber fraction and size on mechanical behavior of coir fiber

reinforced concrete, fiber reinforced concrete with recycled PET bottles and steel fiber

reinforced concrete.

To identify suitable materials to enhance the mechanical properties of concrete.

To prepare guidelines and specifications for future requirements.

RESEARCH SIGNIFICANCE

Concrete has low tensile strength, low ductility and low energy absorption. Therefore

improving the toughness and reducing the amount of defects in concrete would lead to better

concrete performance. An effective way to enhance the mechanical properties of concrete is

by adding a small amount of recycled short fibers to concrete mix.

Concrete with recycled short fibers make positive effects are recycled of waste resources

and protection of environmental containment. Also it is a Provision of an alternative material

for the construction industry.

Waste PET bottles had been reworked for drinking bottles by melting fusion, which turned

out to be too costly.

PET FIBERS PET CHIPS COIR FIBERS


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CHAPTER 02

2.0 LITERATURE REVIEW

2.1 EFFECT OF TEXTILE WASTE ON THE MECHANICAL PROPERTIES OF POLYMER

CONCRETE

(Joo Marciano Laredo dos Reis, 2008)[1] This research contributes to the understanding of

the characteristics of polymer concrete made with recycled textile fibers from clothing

industry.

The mechanical behavior of polymer concrete reinforced with textile trimming waste was

investigated. Two series of polymer concrete formulations were studied, with different

resin/sand (i.e. binder/fine aggregate) weight ratios. In each series, recycled textile chopped

fibers at 1 and 2% of the total weight was used. The textile waste cuttings were trimmed into

average lengths between 2 and 6 cm. Flexural and compressive tests were performed atroom temperature and load vs. displacement curves were plotted up to failure. In the study,

both the influence of fiber content and resin/sand weight ratio were considered relative to the

behavior of polymer concrete reinforced with textile fibers. A decrease in properties was

observed as function of textile fibers content. However, higher textile fibers content lead to a

smoother failure, unlike brittleness failure behavior of unreinforced polymer concrete.

Test Series Resin: sand (w.w-1) Fiber content (%)

FLEXURAL

EPO100F 10:90 0

EPO101F 10:90 1

EPO102F 10:90 2

COMPRESSIVE

EPO120C 12:88 0

EPO121C 12:88 1

EPO122C 12:88 2

Table 01: Mix proportion of PC formulations.


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2.1.1 TEST RESULTS

Figure 2.1: Flexural strength vs Deflection of textile polymer concrete (MPa)

Table 02: Flexural strength test results of textile polymer concrete (MPa)

Specimen EPO100F EPO101F EPO102F EPO120F EPO121F EPO122F

1 20.59 13.24 10.07 24.70 19.46 13.54

2 19.76 15.16 9.25 23.46 19.64 14.62

3 19.14 13.56 10.47 25.28 20.69 12.88

4 20.75 14.93 9.12 24.21 20.35 13.85

5 16.90 13.64 8.98 23.72 18.81 13.53

Average 19.43 14.11 9.58 24.27 19.79 13.68

Table 03: Compressive strength test results of textile polymer concrete (MPa)

Specimen EPO100C EPO101C EPO102C EPO120C EPO121C EPO122C

1 34.35 22.37 19.45 36.45 30.07 24.19

2 33.07 22.04 18.93 51.93 30.83 24.43


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3 27.60 20.43 18.09 44.09 24.09 22.58

4 37.72 23.16 16.07 51.07 18.85 27.15

5 25.78 22.42 17.65 47.65 30.78 22.84

Average 31.70 22.08 18.04 46.24 26.92 24.24

Figure 2.2: Flexural strength vs Deflection of textile polymer concrete (MPa)

Used textile fibers, as reinforcement in ordinary Portland concrete and the results were

satisfactory; showing reduces of strength but not as higher as it happened in polymer

concrete. Textile fibers do not increase polymer concrete flexural and compressive strength

but their addition to the mixture eliminates the signs of brittleness behavior of unreinforced

polymer concrete.

2.3 RECYCLED FIBERS FROM CARPET WASTE

(Wang et al. 1994)[2] Wang et al conducted a laboratory study on concrete reinforcement

with carpet waste fibers. The concrete mix weight ratios were: Type I Portland cement (1.0),

river sand (0.85), crushed granite (0.61), water (0.35), and a small amount of super

plasticizer. The recycled carpet waste fibers used were disassembled from hard carpet waste

(typical length of 1225 mm). Fiber volume fractions for the waste fibers were 1 and 2%.

Only the actual fiber portion was included for calculating fiber volume fractions for the waste

FRC. Fiber Mesh (FM), a virgin polypropylene fiber (19-mm long), at 0.5 and 1% by volume

fractions, was also included for comparison.


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In the compressive test, the plain concrete specimens failed in a brittle manner and shattered

into pieces. In contrast, after reaching the peak load, all the FRC samples still remained as

an integral piece, with fibers holding the concrete matrices tightly together.

In the flexural test, it was observed that the plain concrete samples broke into two pieces

once the peak load was reached, with very little energy absorption. Because of the fiber

bridging mechanism, the energy absorption during flexural failure was significantly higher

than that for plain concrete.

To evaluate the effect of fiber dosage rate on FRC properties, an intensive testing program

was carried out on the flexural and compressive properties of concrete containing 0.89

17.85 kg/m3 of carpet fibers (Wang 1997). Since the carpet waste contains components

other than fibers and since nylon has a higher density than polypropylene, the estimated fiber

volume fraction for the recycled fiber is lower than that with virgin polypropylene, even at the

same dosage rate based on fiber mass. The concrete mix used was cement (1.00), water

(0.44), sand (1.71), crushed rock (2.63), and an appropriate amount of fiber. No chemical

admixtures were added. The test results are summarized in Table 4.

Good workability (180230-mm slump) was reported for mixes with up to 1.8 kg/m3 of waste

fibers. In all the tests, good shatter resistance was observed because of the fiber

reinforcement, especially in those with relatively high fiber dosage rates (Mixes 58).

The flexural strength, corresponding to the maximum flexural load in the test, was similar for

all the mixes, suggesting that the addition of fibers to concrete had little effect upon the

flexural strength of the concrete beams.

Table 03: Test Results for Concrete Reinforced with Carpet Waste Fibres (Wang 1997)


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2.3.2 RECYCLED FIBERS FROM USED TIRES

(Wu et al.1994, 1996)[2] Wu et al studied the use of recycled fibers from used tires and

carpet in concrete to examine their effect on the free shrinkage and restrained shrinkage

cracking behavior of concrete. A total of four types of recycled fibers plus two types of virgin

fibers were used as the reinforcement in concrete.

Three recycled fibers were obtained from disposed tires and one from carpet waste. The tire

fibers included two types of recycled tire fabrics [RTF (1) and RTF (2)] composed of

polymeric tire cords, recycled tire rubber strips (RTR), which were the main component of

tires, and recycled tire steel fibers (RTS). The fibers from recycled carpet waste (RC)

contained backing fibers (usually polypropylene), latex adhesive particles, and small

amounts of face fibers. In addition, hooked-end steel fibers (SF) and FM polypropylene fibers

were also used as virgin fibers for comparison.

Ordinary concrete with river sand and crushed aggregate (maximum size of 9.6 mm, cement:

sand: aggregate = 1:1.72:1.72) was used for form the matrix of the composites. The water-to-

cement ratio was 0.45 and the compressive strength of this concrete was 50 MPa. Recycled

fiber volume fractions in each composite were fixed at 2%, except that the tire steel fiber and

virgin fibers (SF and FM) were used at a 1% by volume fraction.

The free shrinkage of steel fiber reinforced concrete (SFRC) was about 7% lower than that of

concrete, and recycled steel fiber composites (RTSC) showed about the same free shrinkage

as concrete. The crack widths were significantly reduced in the fiber composites including all

recycled fibers except recycled tire rubber composites (RTRC).


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2.4 FIBRE CONCRETE WITH RECYCLED AGGREGATE MASONRY AND CONCRETE

(V Vytlailov, Czech Technical University in Prague, Czech Republic, 2010)[3]This

experiment focused on the assessment of the basic mechanical-physical characteristics of

composites with recycled aggregate and fibers. A series of laboratory trials were carried out

to establish the practical possibility of using Construction and demolition waste material as

replacement for virgin aggregates.

Recycled aggregates consisted in 100% content of natural aggregates. Unclean brick

(masonry) and concrete rubble were shattered in recycling company. For experimental tests

was used synthetic polypropylene fibers FORTA FERRO and BeneSteel with 0.5 % - 1.5 %

of volume content and length 60-90 mm and width 1-2 mm.

Basic mechanical-physical properties as initial bulk densities, compressive strengths, flexural

strengths and tensile-splitting strengths, modulus of elasticity and Poisson coefficient were

determined.


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Average and characteristic resistance diagrams of specimens with 0.5 and 1.0% vol. fibers

FORTA FERRO and masonry rubble (average value from 3 samples)

Samples Recycledaggregate

Type offibers

Volumeof

fibers

Flexuralstrength

Compressive

strength

Modulusof

elasticity% MPa MPa

A1 MRForta Ferro

(Concrete withmasonry)

0.0 1.60 21.85 13.6

A2 MRForta Ferro

(Concrete with

masonry)

0.5 1.85 21.97 14.7

A3 MRForta Ferro


1.0 2.44 19.11 13.6

B1 CRForta Ferro(Concrete)

0.0 1.81 12.71 15.9


0.5 2.09 13.75 14.6


1.0 2.16 13.83 15.3

C1 MRForta Ferro


1.0 - 25.84 -

C2 MRPET(Concrete

with masonry)1.5 - 28.67 -

MR -fiber concrete with masonry / CR -fiber concrete with concrete

Table 04: Test Results for fibbers Concrete


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2.5 COIR FIBER REINFORCED CONCRETE

(Majid Ali1 and Nawawi Chouw, 2010)[4] In this research, rope made of coir fiber is used as

replacement to steel rebars in coir fiber reinforced concrete (CFRC) beams.

For the plain concrete, the mix design ratio for cement, sand and aggregates was 1, 2 and 2,

respectively with a water cement ratio of 0.48. The mix design for coir fiber reinforced

concrete was the same as that of the plain concrete except that (1) the water cement ratio

was 0.56 because of the addition of fiber to make CFRC workable and (2) 7.5 cm long coir

fibers of 3% by weight of cement were added and the same amount (weight) of aggregates

were deducted from the total weight of aggregates. All materials were taken by weight of

cement. The test results are summarized in Table 5.

Sample Cylinder testing Small beam testing Density(kg/m3)

(MPa)

(%)

MOE(GPa)

STS(MPa)

MOR(MPa)

(mm)PCRACK

PC 35.5 0.175 23.2 3.82 4.71 0.64 - 227

CFRC 32.6 0.223 21.1 4.17 5.01 0.69 1.08 2257

Table 5: Static properties of plain and coir fiber reinforced concrete


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CHAPTER 03

3.0 PROPOSED METHODOLOGY

3.1 RAW MATERIALS

OPC, river sand, aggregate, potable water, coir fiber, steel fibers and fibers from PET bottles

will be used for preparation of plain concrete and fiber reinforced concrete.

The maximum size of aggregate : 20mm

The diameter of coir fiber : 0.10 to .75mm

The length of coir fiber : 25 to 200mm

The diameter of steel fiber : 0.25 to 2.06mm

The length of steel fiber : 6.4 to 76mm

The size of PET fiber : 3.6 to 6.2mm squared

3.2 Preparation of fibers

Coir fiber

Coir fibers will be loosed and soaked in water for 30 minutes to soften the fibers and to

remove coir dust. Fibers will be then straightened manually. Wet long fibers will be air dried

to remove approximately 70-80%. Fibers will be cut into the required length.

PET fiber:

Pet fiber will be used from recycle plant directly.

Steel fiber:

Steel fiber will be used from waste of steel manufacturing company.

3.4 MIX DESIGN

Proposed Grade of Concrete : G- 25/20

Workability of mix (Slump) : (30-60 mm)

Fine Aggregate Type : River sand

Free water content : 190 kg/m3

Cement Content : 306.45 kg/m3

Coarse aggregate content : 1045.98 kg/m3

Fine aggregate content : 927.57 kg/m3

We will prepared 150mm 25 cube, 100x100x500mm small three beam and 150x300mm

cylinder three for each mix specimen. And after will be tested with calculation.


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3.5 TESTING PROCEDURE

I. Compressive strength

The compressive strength will be investigated with the laboratory experiment by using a

crushing machine available in the Construction and Materials Laboratory. Three samples will

be tested for each addition and replacement level at 3, 7, 14, 21 and 28 day age. Average

compressive strength at each age will be determined by averaging three correspondingstrength measurements according to BS 1881: Part 121: 1993.

II. Tensile strength

The tensile strength will be determined-- with cylinders 150mm diameter and 300mm height

according to BS 1881: 114. A set off three samples for each specimen will be produced.

III. Flexural strength

The flexural strength will be determined according to BS 1881: 5 1970. A set three small

beams 100mm wide, 100mm deep and 500mm will be produced for each specimen.

IV. Density test and Water absorption test

Density test of the samples will be carried out by measuring its mass and volume for different

days of curing. The sample size for density test will be 150mm x 150mm x 150mm according

to the BS 1881: 114. The sample size for water absorption tests will be 150mm x 150mm x

150mm according to the BS 1881: 122. Samples were immersed in water for 24 hours and

the difference in weight before and after immersion were measured.

3.6 ACTIVITY PLAN


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REFERENCES

1. Aziz, M. A.; Paramaswivam, P.; and Lee, S. L., Concrete Reinforced with Natural

Fibers, New Reinforced Concretes, edited by R. N. Swamy, Surrey University Press,

U.K., pp. 106-140, 1984

2. John, V. M., Cincotto, C., Agopyan, V., and Oliveira, C. T. A.,Durability of slag mortar

reinforced with coconut fiber, 27(5): pp. 565-574, 2005

3. Joao Marciano Laredo dos Reis, 2008, Effect of Textile Waste on the Mechanical

Properties of Polymer Concrete Materials Research, Vol. 12, No. 1, 63-67, 2009

4. Journal of Civil Engineering and Construction Technology Vol. 2(9), pp. 189-197, 16

January, 2012 Available online at http://www.academicjournals.org/jcect

5. Journal of Advanced Concrete Technology Vol. 1, No. 3, pp. 241-252, November 2003

6. Majid Ali and Nawawi Chouw, Effect of fiber content on dynamic properties of coir fiber

reinforced concrete beams, 2010

7. Nguyen, V. 2008, Steel Fiber reinforced ConcreteVol. 05, pp. 108-118, January 20,2008

8. Shah, S. P., and Rangan, B. V., Ductility of Concrete Reinforced with Stirrups, Fibersand Compression Reinforcement, Journal, Structural Division, ASCE, Vol. 96, No. ST6,

1970, pp. 1167-1184.

9. VVytlacilova, Czech Technical University in Prague, Czech Republic, Fiber Concrete

with Recycled Aggregate Masonry and Concrete, 2010

10. Youjiang Wang, H. C. Wu, and Victor C. Li, Concrete Reinforcement with Recycled

Fibers, 2000

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Proposal Correction