finite element analysis on experimentally studied ... · attempt is made to use finite element...

International Journal Of Advancement In Engineering Technology, Management and Applied

Science (IJAETMAS)

UGC APPROVED JOURNAL (Number-63082)

ISSN: 2349-3224 || www.ijaetmas.com || Volume 05 - Issue 02 || February-2018 || PP. 97-111

www.ijaetmas.com Page 97

Finite Element Analysis on Experimentally Studied

Alccofine Concrete by Partial Replacement of cement

Dr G Elangovan1, G Vimal Arokiaraj

2

1HOD, Department of Civil Engineering, University College of Engineering Thirukkuvalai, Nagappattinam District,

Tamil Nadu, India

2Research Scholar, Department of Civil Engineering, University College of Engineering Thirukkuvalai,

Nagappattinam District, Tamil Nadu, India

Abstract :- This experimental work deals with the effects of Alccofine in the

concrete, by partial replacement of cement in compressive strength. In this program 36

cube samples of size 150 mm were cast for different percentages of Alccofine with partial

replacement of cement at the percentages of 0%, 2.5%, 5%, 7.5%, 10%, and 12.5%. From

the test results, it was found that strength was increased with the increase of alccofine in

the concrete after 7 days and 28 days curing. For the experimental values best fit models

were also developed. From the model one can easily predict the experimental values for any

percentage of alccofine. Also using ANSYS software all the concrete cubes were studied by

plane stress model with constant strain triangle to find out deformation, principal stresses

and shear stresses.

Keywords: Alccofine, Principal Stress, Shear Stress, Nodal Displacement, Stress Contour.

I INTRODUCTION

Alccofine is a new generation, micro fine material of particle size much finer than other

hydraulic materials like cement, fly ash, silica etc. being manufactured in India. Alccofine has

unique characteristics to enhance 'performance of concrete' in fresh and hardened stages due to

its optimized Particle size distribution. It can be used as practical substitute for Silica Fume as it

has optimum particle size distribution. It is manufactured in the controlled conditions with

special equipments to produce optimized particle size distribution which is its unique property.


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Alccofine 1203 and Alccofine 1101 are two types of Alccofine with low calcium silicate and

high Calcium silicate respectively. Alccofine 1200 series is of 1201, 1202, 1203 which

represents fine, micro fine, ultrafine particle size respectively.

II LITERATURE REVIEW

Many researchers have investigated the possible use of alccofine as a concrete aggregate. For

this investigation, some of the important literatures were reviewed and presented briefly.

Mechanical strength development of high strength concrete (M50) with partial replacement of

cement by ultra-fine slag (alccofine) is carried out by Saurav et al. Comparison is done between

cubical strength and cylindrical strength of M50 grade concrete using ultra-fine slag. Siddharth et

al suggested in their research that Ordinary Portland cement-fly ash-Alccofine concrete was

found to increase the compressive strength of concrete on all age when compared to concrete

made with fly ash and Alccofine alone. Ansari et al conducted cement is partially replaced by

alccofine and fly ash for M70 grade of concrete. The compressive strength of concrete increases

with increase alccofine and fly ash content in HPC up to 15-20%. Similarly Devalsoni et al

studied on strength of concrete of grade M80 with different proportions of Alccofine and fly ash

in the mix and to find optimum range of Alccofine and fly ash content in the mix. Concluded

that-Alccofine has better performance compare to other slag materials and micro silica. Pawar et

al concluded in their experimental work that the addition of Alccofine in SCC mixes increases

the self compatibility characteristic like filling ability, passing ability and resistance to

segregation. Fresh Properties and harden Properties of SCCs with 10% Alccofine are superior

than SCCs with5% and 15% of Alccofine. But in all the study no experimental work is

conducted for M25 grade concrete and also not studied for finding principal stresses. Hence an

attempt is made to use finite element analysis on M25 grade concrete with Alccofine material.

III EXPERIMENTAL WORKS

MATERIALS USED

The grade of cement is 53 with specific gravity of 3.12. The initial time and final setting time

were found to be 30min and 600min respectively. The fine aggregate are taken in saturated

surface dry condition. Local aggregate comprising 20mm, and less than 20mm coarse aggregates


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in saturated surface dry condition, were used. All the preliminary tests were conducted as per

IS: 383-1970. Table 1 shows preliminary test results of concrete materials. Table 2 shows

physical and chemical properties of Alccofine material used. In this work Alccofine 1203 was

used. Water is the key ingredient mixed with cement, forms a paste that binds the aggregate

together. The water causes the hardening of concrete through a process called hydration. Excess

of water reduces increases workability and decreases strength of concrete.

Table 1 PRELIMINARY RESULTS

TESTES MARERIALS VALUES

Specific gravity G

Fine aggregate 2.51

Coarse aggregate 2.60

Alccofine 2.84

Cement 3.12

Sieve analysis

Fine aggregate 4.60 %

Coarse aggregate 4.05 %

Water Absorption

Fine aggregate 1.5 %

Coarse aggregate 0.51%

Table 2 PHYSICAL AND CHEMICAL PROPERTIES OF ALCCOFINE USED

Physical and Chemical

properties Alccofine

Colour White

Specific gravity 2.86 ± 0.02

Appearance Powder

Bulk Density (kg/m3) 600-700


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Glass content >90%

Silica dioxide (SiO2) 33-35 %

Calcium oxide (CaO) 31-33 %

Aluminum oxide (Al2O3) 23-25 %

IV EXPERIMENTAL RESULTS and DISCUSSION:

Based on the preliminary test results concrete mix was designed as per IS: 10262-2009. Grade of

the concrete was M25. Mix ratio is 1: 1.12: 2.24: 0.4. In this program 36 cube samples of size

150 mm were cast for different percentages of Alccofine with partial replacement of cement at

the percentages of 0%, 2.5%, 5%, 7.5%, 10%, and 12.5%. All the experimental test results like

workability test, compressive strength after 7 days and 28 days are presented in table3. From the

table 3 it is found that workability of concrete goes on reducing while increasing Alccofine. But

on the contrary compressive strength goes on increasing with increased percentage of Alccofine.

From figure 1 and 3, Max percentage improvement over reference concrete was found as 23.86

and 16.49.

Table 3 COMPRESSIVE STRENGHT TEST ON CONCRETE CUBE

Mix Workability Test Compressive Strength N/mm2 after

Slump Value 7 Days curing 28 Days curing

AF0 60 34.66 39.00

AF1 55 34.81 39.83

AF2 53 37.33 40.10

AF3 38 39.41 41.70

AF4 30 40.00 43.67


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AF5 21 42.93 45.43

From the test results slump value for the reference mix is 60mm it is value goes on reducing up

to 21 mm on increasing alccofines. The compressive strength for reference mix 34.66

N/mm2,while adding alccofine the compressive strength was found be increase up to 42.93

N/mm2 under 7 days curing.The compressive strength for reference mix 39N/mm2, while adding

alccofine the compressive strength was found be increase up to 45.43 N/mm2 under 28 days

curing. It can be easily predicted compressive strength of Alccofine concrete after 7 and 28 days

curing by using best fit models shown in figure 2 and 4. From the experiment results optimum

percentage of alccofine is found as 2.5% for the mix AF1. All the values are closely matched

with experimental values by referring R2

values as 0.967 and 0.991 from figures 2 and 4.

Figure 1. Compressive Strength after 7 Days Curing

34.66 34.8137.33

39.41 4042.93

0.00 0.43

7.70

13.70 15.41

23.86

05

101520253035404550

AF0 AF1 AF2 AF3 AF4 AF5

CO

MP

RES

SIV

E ST

REN

GTH

&

% O

F IN

CR

ESIN

G S

TREN

GTH

ALCCOFINE

COMPRESSIVE STENGTH FOR 7 DAYS


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Figure 2. Best Fit Model for Compressive Strength after 7 Days Curing

y = 0.017x2 + 0.453x + 34.34R² = 0.967

30

32

34

36

38

40

42

44

0 2 4 6 8 10 12 14

CO

MP

RES

SIV

E ST

REN

GTH

% OF ALCCOFINE

COMPRESSIVE STRENGTH FOR 7 DAYS

39 39.83 40.141.7

43.6745.43

0.002.13 2.82

6.92

11.97

16.49

0

5

10

15

20

25

30

35

40

45

50


CO

MP

RES

SIV

E ST

REN

GTH

&

% 0

F IN

CR

ESIN

E ST

REN

GTH

ALCCOFINE



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Figure 3. Compressive Strength after 28 Days Curing

Figure 4. Best Fit Model for Compressive Strength after 28 Days Curing

V PLANE STRESS ANALYSIS by CST ELEMENTS

All the concrete cubes of various mixes are modeled by ANSYS software for plane stress

analysis by considering one fourth of the concrete cube with 1mm thickness. Size of the

model is taken 75mmx75mmx1mm thick as continuum. This continuum is discretized

into eight elements and each element is assigned as three nodded constant strain triangle

elements CST. Young’s modulus and poison’s ratio were taken as 38E5 and 0.3

respectively. Loading is applied corresponding to each mix at node No.1. Stress resultant

like displacements, normal stress and shear stress were noted for all the concrete cubes in

both x and y direction. From these stresses, major and minor principal stresses are

calculated along with maximum shear stress. Maximum major and maximum minor

principal stresses for all the mixes are shown in figures 5, 6, 7 and 8. Element numbering

and node numbering are shown in figure 9a. Major Principal tensile stress is found

invariably found in element No. 6 for all the mixes. These tensile stresses are responsible

y = 0.032x2 + 0.108x + 39.07R² = 0.991

38

39

40

41

42

43

44

45

46

0 2 4 6 8 10 12 14

CO

MP

RES

SIV

E ST

REN

GTH

% OF ALCCOFINE



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for crack propagation in the concrete. First crack may be developed as soon as tensile

stress exceeds the permissible tensile strength of concrete as per IS:456-2000. Maximum

shear stress is also found in element No.2. Influence of shear stress generally increases

tensile strength of concrete. Maximum minor principal stresses are mostly compressive

stresses and found in element No 2. Consequently it was found that crack formation over

concrete cube was greatly reduced and found as only micro crack alone formed due to

high compressive strength. Similarly stress contours are shown and limited for AF0 and

AF1 mixes having 7 and 28 days curing respectively as it was considered about

performance of concrete at optimum percentage alccofine. These are shown in figures 9,

10, 11 and 12.

Figure 5. Major Principal Stress (Tension) after 7 Days Curing

0

5

10

15

20

25



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Figure 6. Minor Principal Stress (Compressive –ve) after 7 days Curing

0

20

40

60

80

100

120

140


17

17.5

18

18.5

19

19.5

20

20.5

21

21.5

22

22.5



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www.ijaetmas.com 6

Figure 7. Major Principal Stress (Tension) after 28 Days Curing

Figure 8. Minor Principal Stress (Compressive –ve) after 28 Days Curing

9a) DISPLACEMENT DIAGRAM 9b) CONTOUR OF NODAL DISPALCEMENT

105

110

115

120

125

130

135

140



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9c) MAX MAJOR PRINCIPAL STRESS @Element6 9d) MAX MINOR PRINCIPAL STRESS @Element 2

Figure 9. Stress Contour of Concrete Mix after 7 Days Curing



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10c) MAX MAJOR PRINCIPAL STRESS @Element 6. 10d) MAX MINOR PRINCIPAL STRESS @Element 2

Figure 10. Stress Contour of Concrete Mix with 2.5% Alccofine after 7 days Curing



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Figure 11. Stress Contour of Concrete Mix after 28 Days Curing



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Figure 12. Stress Contour of Concrete Mix With 2.5% Alccofine after 28 Days Curing

VI CONCLUSION

Based on the test results obtained from the experimental program the following major

conclusions are arrived from workability, compressive strength.

1. From the workability test results, slump value slightly decreases for concrete mixes

with alccofine when compared with reference concrete mix.

2. Compressive strength of concrete mix AF1 has higher strength than reference mix

after 7 days and 28 days curing. The compressive strength for reference mix 34.66

N/mm2, while adding Alccofine the compressive strength was found be increase up

to 42.93 N/mm2 under 7 days curing. The compressive strength for reference mix


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39N/mm2, while adding alccofine the compressive strength was found be increase up

to 45.43 N/mm2 under 28 days curing.

3. Optimum percentage of Alccofine for the M25 grade concrete is 2.5%.

4. Best fit models are presented for Alccofine concrete mix after 7 and 28 days curing.

5. Displacement diagram and stress contours are presented for tested concrete mixes.

6. Major and Minor principal stresses are calculated for Alccofine concrete mixes after

7 days and 28 days curing by finite element analysis.

REFERENCES

1. Saurav, Ashok Kumar Gupta , “Experimental study of strength relationship of concrete cube

and concrete cylinder using ultrafine slag Alccofine” International Journal of Scientific &

Engineering Research, Volume 5, Issue 5, May-2014.

2. Siddharth P Upadhyay and M. A. Jamnu, “Effect on Compressive Strength of High

Performance Concrete Incorporating Alccofine and Fly Ash”, International Journal of

Innovative Research & Development, 3(2), 2014, 124-128.

3. Deval Soni, Suhasini Kulkarni, Vilin Parekh, “Experimental Study on High-Performance

Concrete, with Mixing of Alccofine and Flyash”, ISSN Volume: 3 Issue: 4 May 2013.

4. M.S. Pawar, A.C. Saoji, ― “Effect of Alccofine on Self Compacting Concrete”, International

Journal of Engineering And Science (IJES) Volume 2, Issue 6, Pages 05-09, 2013.

5. IS:10262-2009, “Indian Standard recommended guidelines for concrete mix design”, Bureau

of Indian Standards, New Delhi, 2009.

6. IS:383-1970, “Indian Standard specifications for coarse and fine aggregates from natural

sources for concrete”, Bureau of Indian Standards, New Delhi, India.

7. IS:456-2000, “Code of practice for plain and reinforced concrete Bureau of Indian

standards”, New Delhi, India.

8. “Concrete Technology – theory and practice”, by M S Shetty, S. Chand Company Ltd, Delhi,

First multicolour illustrative revised edition, reprint 2008.

9. “The Failure of Concrete Test Specimens for Civil Engineering”, Neville A.M., July, 1957.

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