EXPERIMENTAL STUDY ON SISAL FIBER REINFORCED CONCRETE · Researchers have used natural fibers as an alternative to steel or synthetic fibers in the composites such as cement paste,

International Journal of Technical Innovation in Modern

Engineering & Science (IJTIMES) Impact Factor: 3.45 (SJIF-2015), e-ISSN: 2455-2585

Volume 4, Issue 5, May-2018

IJTIMES-2018@All rights reserved 641

EXPERIMENTAL STUDY ON SISAL FIBER REINFORCED CONCRETE

Meduri Pushpalatha1, Polu Sathish

2

1PG Student, Structural Engineering, VFSTR Deemed to be University,[email protected].

2 Assistant professor, Dept. of civil engineering, VFSTR Deemed to be University,[email protected]

Abstract – The main objective of this paper was to investigate the performance of the M40 grade of the concrete and

reinforced with sisal fiber were used in the concrete matrix with w/c ratio 0.4 and to study its improvements in

strength properties. The sisal fibers of various proportions from 0% to 1.5% by the weight of cement with the aspect

ratio 50 The parameter of the investigation includes the compressive strength, split tensile strength, flexural

strength. The result shows that the notable increase in the split tensile strength and flexural strength. Strength

models were established to predict the compressive strength, splitting tensile strength and flexural strength of the

fiber reinforced concrete. The result shows that the strength models give the prediction matching the experimental

measurements.

Keywords-Sisal fibers, Compressive strength, Split tensile strength, Flexural strength, SEM analysis, Statistical

Models.

I. INTRODUCTION

In the present scenario, concrete is one of the most required materials in the construction industry because of its high

compressive strength and other properties. Concrete is generally made with the ordinary Portland cement and it is

strong in compression but weak in tension and tends to be brittle. So we will provide the reinforcement to the concrete.

Majority steel is used as reinforcement. Many of researchers are in progress to find a substitute this material like

artificial fibers, natural fibers and to some extent by the inclusion of the sufficient volume hybrid of the fibers. The

introducing of the fibers in the concrete to increase its properties like tensile strength, flexural strength.

Fiber reinforced concrete is a composite material essentially consists of conventional concrete reinforced by the

fine fibers. During the last three decades research work is going on the fiber reinforced concrete using the advanced

composite materials to enhance the properties of the concrete by using the fibers. Fiber reinforcement is commonly

used to provide toughness and ductility to brittle cementitious matrices and also improves the structural integrity.

Researchers have used natural fibers as an alternative to steel or synthetic fibers in the composites such as

cement paste, mortar, and concrete. The interest in natural fiber reinforced composite materials is rapidly growing both

in the terms of their industrial applications and fundamental research. They are renewable, cheap, fully or partially

recyclable and biodegradable. Their availability, renewability, low density, and price as well as satisfactory mechanical

properties make them an attractive ecological alternative to metallic and non-metallic fibers used for the manufacturing

of composites. The natural fiber containing the composites is more environmentally friendly and is used in the building

and also in construction industries.

In this study Sisal fibers are used as a reinforcing material in the concrete that is competitive with synthetic

composite is gaining the attention over the last decades. Because they are renewable, biodegradable and

environmentally friendly.

International Journal of Technical Innovation in Modern Engineering & Science (IJTIMES) Volume 4, Issue 5, May-2018, e-ISSN: 2455-2585,Impact Factor: 3.45 (SJIF-2015)


II. MATERIALS USED

2.1Cement-

Ordinary Portland cement confirming to 53 Grade (as per IS 12269:1993) was used throughout the study. The

basic properties of the cement are shown in the table no: 1

Table-1: Basic properties of cement

Properties Cement

Fineness 5%

Specific Gravity 3.15

Standard Consistency 30%

Initial Setting Time 40minutes

Final Setting Time 480 minutes

2.2 Fine Aggregate-

The Fine Aggregate used in this Investigation was clean river sand conforming to grading zone-2 as per IS: 383-

1970. The sand is sieved using 4.75 mm sieve to remove all the pebbles. The properties of the fine aggregate are shown

in the table no: 2

Table-2: Basic properties of fine aggregate

Properties Fine aggregate

Specific Gravity 2.98

Fineness Modulus 2.8

2.3 Coarse Aggregate-

The crushed stone aggregate of 20mm size downgraded to 12.5 mm obtained from local crushing plants are used

as coarse aggregate in the present investigation. The properties were determined as per IS 383-1970. The basic

property of the coarse aggregate is shown in the table no: 3

Table-3: Basic properties of coarse aggregate

Properties Coarse aggregate

Specific gravity(20mm,12.5) 2.8,3.025

Shape Angular

2.4 Water-

Potable water used throughout this study. For the concrete the permissible limits are according to IS: 3025 .the

basic properties of the water are shown in the table no: 4

Table-4: Basic properties of Water

Properties Water Permissible Limits

pH 6.68 6.0-9.0

Sulphates(PPm) 380 400

Chlorides(PPm) 300 1000

2.5 Super plasticizer-

There is high range water reducing admixture to improve plasticity in the fresh concrete. These are generally used

for achieving higher strength by reducing the water-cement ratio or for improving workability. Conplast sp 430 is used

as a super plasticizer in the present investigation.



2.6 Sisal fiber-

The sisal fiber is derived from a plant botanically known as agave sisalana. Sisal fiber is an agave that yields a stiff

fiber traditionally used in making twine rope and also dartboards. The sisal fiber does not absorb moisture and dust,

hence are anti-static. They don’t wear and tear easily and thus require less maintenance. Using borax with sisal fiber

render those to be fire resistant. They naturally have shock and sound absorbing properties. In the present investigation,

treated sisal fiber is used, the length of the sisal fiber is 15mm.

(a) (b)

Figure 1: (a) Agave sisalana (b) Sisal fi Table -5: Chemical composition of sisal fiber

Table-6: Physical properties of sisal fiber

2.7Extraction of the sisal fiber-

The sisal leaves are cut from sisal plant and tied into bundles by using bags. Then bags contain the sisal leaves are

retted in tanks or River or well for 3-4 days. The retted leaves are washed in running water and the top portion of the

leaves are removed by manually (May by removed mechanically) to get the fiber separately and cleaned and dried in

the sun.

(a) (b)

(c) (d) (e)

Figure 2: Extraction of sisal fibers (a) Sisal Plant (b) Retting in water for 3-4 days (c) Remove the top portion

of the leaves (d) dried under the sunlight (e) final form of sisal fiber.

Cellulose 65%

Hemi cellulose 12%

Lignin 9.9%

Waxes 2%

Total 100%

Fiber type Sisal

Fiber length(m) 0.5-1

Fiber diameter(m) 0.21-0.29

Tensile strength(n/mm2) 31-221

Elongation (%) 14.8

Specific gravity 1.4

Elastic modulus(Gpa) 7.83



2.8 Sisal fiber treatment-

Sisal fiber is treated with the NaOH solution of 0.1normality to attain the high performance in crack resistance and

durability in sisal fiber concrete. When the treated fibers were incorporated into an epoxy matrix, mechanical

characterization of the laminates revealed the importance of two types of interface: one between fiber bundles and the

matrix and other between the ultimate cells.

(a) (b)

Figure 3: (a) Untreated sisal fiber (b) Treated sisal fiber

III. EXPERIMENTAL PROGRAMME

3.1Concrete Mix design-

The concrete mix of grade M40 was designed as per the IS 10262:2009 is 1:2.228:3.124 with water cement ratio is

0.4.

Table-7: Mix proportion per cubic meter

3.2Casting and curing of the specimens- Mixing was done by the hand. For each proportion 6 cubes, 6 cylinders, 3 beams were cast. Mixing was done by

adding the coarse aggregates, followed by 25% of total water. Then fibers and sand were added with 25% of

remaining water super plasticizer will be added to water measured and stirred well. After thoroughly mixing of

aggregates, cement was added and remaining 50% of water and super plasticizer was added. For each mix slump test

was conducted to measure the workability. Totally 66 cubes, 48 cylinders, 33 beams were cast. After casting concrete

is filled into the moulds and compacted on the vibration table. Demoulding was done after 24 hours of casting. The

specimens were cured in the curing tank. Water immersion method of curing was adopted.

Figure-4: Casting and Curing of the Specimens.

Mix Sisal Fiber (Kg) Cement (kgs) FA (kg) CA (kg) Water (liters) SP (liters)

C.C 0 383.16 854 1197 153.2 3.83

0.5% S.F 1.92 383.16 854 1197 153.2 3.83

1% S.F 3.83 383.16 854 1197 153.2 3.83

1.5%S.F 5.75 383.16 854 1197 153.2 3.83



3.3Testing of specimens-

Generally the compressive strength tests were carried on the cubes, the split tensile test on the cylinders, and the

flexure test on beams. The compressive strength test and split tensile strength test are done in the compressive testing

machine and flexure strength test is carried on the flexure testing machine.

3.4 SEM Analysis-

SEM test is the actual way to study the microstructure of the hydrated cement based products. To assessment, the

bond characteristics of concrete mix with different percentages of the fiber addition at 28days, the microstructure of fiber

reinforced concrete were studied by means of SEM.

Sisal fiber

Figure: 5 SEM Image of sisal fiber at 7 days

Sisal fiber

Figure- 6: SEM Image of sisal fiber at 28 days

IV. ANALYTICAL STUDY

A statistical model is formalization between variables in the form of mathematical equations. It describes how

one or more random variables are related to other variables. It is used to improve the experimental methods, in which,

instead of selecting one starting mix proportion and then adjusting by trial and error for achieving the optimum

solution. In this study linear multiple regression analysis is used



The regression equation is written as,

Y = a + b1X 1+b2X2

y = value of the dependent variable

x = value of the independent variable

a = intercept

b = slope of the regression line

Statistical package for the social sciences (SPSS) is a window based program that can be used to perform data

entry and analysis and to create tables and graphs.

Figure-7: Schematic Diagram of Regression Equation System

V. RESULTS AND DISCUSSIONS

4.1Compressive strength test

Compression test is the most commonly conducted test as it is the most desirable characteristic property of the

concrete. In this investigation cube moulds of size150×150×150 were tested for knowing the compressive strength of

the concrete for different mixes at 7 days and 28 days

Figure – 8: 7 days and 28 days compressive strength of S.F variation in the concrete mix

Figure 11 shows 7 days and 28 days compressive strength of the concrete. It shows that the when S.F is added to

the concrete. With increasing the percentage of the fiber in the concrete it leads to increases the compressive strength of

the concrete 513%, 9.98%, and 0.12% for 28 days.

0

10

20

30

40

50

C.C 0.5% S.F 1% S.F 1.5% S.F

Co

mp

ress

ive

Str

eng

th

(Mp

a)

Compressive Strength of S.F Variation

7 Days

28 Days



4.2 Split tensile strength test

According to IS 5816-1999 split tensile test has been carried out on standard cylinder specimens (150 mm diameter

and 300 mm long) after curing.

Figure -9: set up for the split tensile strength

Figure-10: 28 days split tensile strength of S.F variation in the concrete mix

Figure 10 shows 28 days split tensile strength of the concrete. It shows that the when S.F is added to the concrete.

With increasing the percentage of the fiber in the concrete it leads to increases the split tensile strength of the concrete

6.23%%, 13.27%, 23.65% for 28 days.

4.3Flexural strength test

The flexural strength test is conducted on the prism specimens.

Figure-11: set up for the flexural strength

0

1

2

3

4

C.C 0.5% S.F1% S.F1.5% S.F

Sp

lit

ensi

le s

tren

gth

(MP

a)

Split Tensile Strength of S.F

Variation

28 Days



Figure-12: The flexural strength of S.F variation in the concrete mix

Figure 12 shows 28 days flexural strength of the concrete. It shows that the when S.F is added to the concrete. With

increasing the percentage of the fiber in the concrete it leads to increases the flexural strength of the concrete 10.83%,

17.60%, and 20.99% for 28 days.

4.4Simple linear regression models for compressive strength (fck)-

The results of the regression analysis of cube compressive strength (fck) considering the percentage of the sisal fiber

(X1) for 28 days of curing period of statistical modeling is presented in the below table.

Table-8: Comparison of Experimental and Statistical Results for Compressive Strength of HFRC

SI.NO % of fiber

S.F addition

The Compressive strength of HFRC (MPa)

Experimental Measured (SPSS)

1 0 41.28 40.989

2 0.5 39.29 39.859

3 1.0 38.99 38.727

4 1.5 37.61 37.596

The linear regression model has been obtained for M40 grade of concrete for compressive strength is shown in the

equation

Y = 40.989-2.262X1

4.3Simple linear regression models for split tensile strength –

The results of the regression analysis of split tensile strength considering the percentage of Sisal fiber(X1) for 28

days of curing period of statistical modeling is presented in the below table.

Table-9: Comparison of Experimental and Statistical Results for split tensile Strength of HFRC

SI.NO % of fiber

S.F addition

Split tensile strength of HFRC (MPa)


1 0 2.98 2.965

2 0.5 3.09 3.1

3 1.0 3.21 3.235

4 1.5 3.39 3.37

The linear regression model has been obtained for M40 grade of concrete for split tensile strength is shown in the

equation.

Y = 2.965+0.27X1

0

1

2

3

4

5

6

C.C 0.5% S.F 1% S.F 1.5% S.F

Fle

xu

ral

Str

en

gth

(MP

a)

Flexural Strength of S.F

Variation

28 Days



4.4Simple linear regression models for flexural strength-

The results of the regression analysis of cube flexural strength considering the percentage of the Sisal fiber(X1) for

28 days of curing period of statistical modeling is presented in the below table.

Table-10: Comparison of Experimental and Statistical Results for Flexural Strength of HFRC

SI.NO % of fiber

S.F addition

The Flexural strength of HFRC (MPa)


1 0 4.43 4.389

2 0.5 4.51 4.538

3 1.0 4.62 4.687

4 1.5 4.89 4.836

The linear regression model has been obtained for M40 grade of concrete for flexural strength is shown in the

equation

Y = 4.619+0.119X1+1.583X2

VI. CONCLUSION

The following are the observations drawn from the present investigation

The compressive strength of the concrete increases with increasing the percentage of the sisal fiber. At 1% S.F

the compressive strength of the concrete increases 9.98% than that of the conventional concrete at 28 days.

The split tensile strength of the concrete increases with increasing the percentage of the sisal fiber.

The flexural strength of the concrete increases with increasing the percentage of the fiber in the concrete mix.

The maximum flexural strength is obtained at 0.28% S.F that is 20.99% than that of the conventional concrete

SEM result shows the optimum length is available for proper bonding between the concrete matrix and fiber, the

reason for good tensile strength and flexural strength compared to normal concrete mix.

The regression equations are developed for predicting the mechanical properties of the fiber reinforced concrete

and observed that there is a minor difference between the predicted and experimental results.

REFERENCES

[1] A.Supraja, T.Avinash “strength properties of sisal fiber concrete with 30 % partial replacement of ground

granulated blast furnace slag” International Journal of Engineering Research and Technology November 2017.

[2] Abdul Rahuman, Sai Kumar yeshika “Study On Properties Of Sisal Fiber Reinforced Concrete With Different

Mix Proportions And Different Percentages Of Fiber Addition” International Journal of Research in Engineering

and Technology March 2015.

[3] Jithendra D.Dalvi, Uttam B.Kalwane “Effect of fiber length and percentage of sisal on strength of concrete”

Multidisciplinary Journal of Research in Engineering and Technology March 2016.

[4] K.T Radha Sumithra, ABS Dadapheer “Experimental investigation on sisal fiber reinforced concrete

“International Journal of Engineering Research and Technology April 2017.

[5] K.V.Sabarish, K.Dhanasekhar“Strength and Durability Evaluation of Sisal Fiber Reinforced Concrete

“International journal of civil engineering and technology September 2017.

[6] Kavitha Sajjala, Felix kala “Bamboo Fiber Analysis by Scanning Electron Microscope Study” International

Journal of Civil Engineering and Technology August 2016.

[7] Sunil Raiyani, Purvi Karanjiya “XRD and SEM Analysis Of Bio Fiber Reinforced Concrete” Conference: 7th

National Conference on Emerging Vistas of Technology in 21st Century, At Parul University, Baroda, and Volume:

7, April 2016.

Documents

EXPERIMENTAL STUDY ON SISAL FIBER REINFORCED CONCRETE · Researchers have used natural fibers as an alternative to steel or synthetic fibers in the composites such as cement paste,