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Second International Conference on Recent Advances in Science & Engineering-2015
Experimental Study on Glass Fiber Reinforced
Concrete with Steel Slag and M-Sand as
Replacement of Natural Aggregates
Anil Kumar M
M.Tech Scholar
Vijaya Vittala Institute of Technology
Bangalore
Prof. Virendra Kumar K N
Civil Engineering Department
Vijaya Vittala Institute of Technology
Bangalore
ABSTRACT
The use of Glass Fiber Reinforced Concrete (GFRC) has been increasing due to rapid growth of
urbanization. But, due to increase in use of conventional materials for GFRC has increased the cost of
production and also has negative impact on environment due to excessive mining and use of these materials for
the production of GFRC. In the present work, an experimental study was made to assess the suitability of Fly
Ash, Steel Slag and M-Sand as replacement for cement, coarse aggregate and river sand respectively. Mix
design for M60 grade was done using 0.2% of glass fibers. Steel Slag and M-Sand were added as replacement in
25%, 50%, 75% and 100% to determine the optimum replacement level; also cement was replaced with fly ash
by constant 30% for all variations. Strength and durability tests were conducted for 7, 14 and 28 days.
Experimental study showed that replacement level of 75% gave satisfactory results when compared with
conventional concrete.
Keywords—Glass Fibers, Fly ash, Steel Slag, M-Sand
I.
INTRODUCTION
Concrete is the most widely used material in construction industry. Concrete with high strength along
with long term durability, serviceability are the need of the day. Glass Fiber Reinforced Concrete consists of
hydraulic Portland cement, coarse and fine aggregates along with alkali resistant glass fiber as reinforcement
material. Natural aggregates are preferred for concrete but excessive mining of natural aggregates has caused
environmental degradation. So, search for alternative to natural aggregates has already begun. Steel Slag a byproduct obtained from steel manufacturing industry can be used as coarse aggregate replacement. M-Sand a byproduction obtained from crushed rock during aggregate production can be used as fine aggregate replacement.
Also fly ash which has cementitious property obtained from thermal power plant can be used for replacement of
cement in concrete up to certain extent. Experimental studies of previous researchers have shown that addition
of glass fibers enhances strength and durability of concrete.
II. Previous Works
Steel Slag as partial replacement of coarse aggregate was experimentally studied [1] and found that
steel slag can be replaced 100% without reduction of strength of concrete. Concrete with steel slag as coarse
aggregate replacement and eco sand as fine aggregate replacement was studied [2], which indicated that steel
slag can be replaced up to 60% and eco sand can be replaced up to 40% without any adverse effect on the
strength of concrete. Crushed rock powder as replacement of fine aggregate in concrete was experimentally
evaluated [3], results showed that crushed rock powder can be replaced up to 40% without reduction in strength
properties. Use of m-sand as fine aggregate replacement in concrete was studied [4], and results indicated that
m-sand can be replaced up to 50% also reducing the cost of fine aggregate for the production of concrete. Fine
aggregate replacement by crushed stone dust was experimentally carried out [5], and results showed that
crushed stone sand can be effectively replace natural sand in concrete. Glass Fiber Reinforced Concrete and its
properties was studied [6], and found that alkali resistant glass fiber used in concrete showed increase in
strength properties than normal concrete. Suitability of steel slag as coarse and fine aggregate replacement was
experimentally studied [7], and results showed that steel slag up to 100% replacement had no adverse effect on
strength of concrete. Very few literatures are available regard to the use of steel slag and m-sand combined. The
present study examines the possibility of using steel slag and m-sand as partial/full replacement of coarse and
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Second International Conference on Recent Advances in Science & Engineering-2015
fine aggregate respectively. Also fly ash as replacement of cement by constant 30% for all variations with 0.2%
of glass fibers as reinforcement material.
III. Materials Used
A. Cement
The cement used was ordinary Portland cement of 53 grade with specific gravity of 3.14. The initial
and final setting time of cement was 46 minutes and 192 minutes respectively.
B. Fly ash
In this study, fly ash is used as replacement of cement by constant 30% for all variations and is
collected from Raichur Thermal Power Station, Karnataka. It has specific gravity of 2.1 and normal consistency
of 31%.
C. Coarse aggregate and Steel Slag
The coarse aggregate of 20mm and below size were used in study. Steel Slag is obtained from JSW,
Bellary for the present study.
Table 1: Properties of Coarse aggregate and Steel Slag
Particular
Shape
Bulk density of compacted aggregate
Bulk density of loose aggregate
Specific Gravity
Water absorption
Coarse Aggregate
Angular
1562 kg/m3
1368 kg/m3
2.67
0.2%
Steel Slag
Angular
1628 kg/m3
1452 kg/m3
3.34
1.5%
D. River Sand and M-Sand
The river sand and m-sand used in the present study conforms to IS: 2368-1968. The m-sand was
supplied by Bharathi Cements, Bangalore.
Table 2: Properties of River Sand and M-Sand
Particular
Bulk density of loose sand
Bulk density of compacted sand
Specific Gravity
Water Absorption
Zone
River Sand
1428 kg/m3
1624 kg/m3
2.62
0.9%
II
M-Sand
1898 kg/m3
1645 kg/m3
2.61
3.6%
II
E. Fibers Used
In the present work, Cem-Fil anti crack glass fibers of length 12mm and aspect ratio 58 is used.
F. Water
Ordinary potable water was used for mixing and curing purpose.
G. Super-plasticizer and Mix Proportion
Glenium 8233 is used for the work. The percentage of super-plasticizer is 0.6% of total cementitious
quantity.
Table 3: Mix Proportion of M60 grade concrete
Material
Cement
Fly Ash
River Sand
Coarse Aggregate
Water
Quantity
379.53 kg/m3
162.65 kg/m3
616.06 kg/m3
1115.8 kg/m3
159.27 kg/m3
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IV. Methodology
A. Compressive Srength Test
The compressive strength test was carried out on cube specimens of 150 x 150 x 150 mm size prepared
in accordance with I.S: 516-1959 at 7,14 and 28 days using compression testing machine. The details of the six
different specimens are as given in Table 4.
Table 4: Details of Test Specimens
Fine Aggregate (%)
Mix
Designation
Cement + Fly
Ash (%)
River Sand
M-Sand
CC
A0
A25
A50
A75
A100
100+0
70+30
70+30
70+30
70+30
70+30
100
100
75
50
25
-
25
50
75
100
Coarse Aggregate (%)
Natural
Coarse
Steel Slag
Aggregate
100
100
75
25
50
50
25
75
100
% of Glass
Fiber by
volume of
concrete
0.2
0.2
0.2
0.2
0.2
B. Split Tensile Strength Test
Cylinder specimens of 150mm diameter and 300 mm length were cast and placed horizontally in
compression testing machine with wooden plates at the top and bottom. The split tensile test was conducted
after curing periods of 7, 14 and 28 days. The load was applied at the top without shock and increased
continuously at a rate within the range 1.2 N/mm2/minute to 2.4 N/mm2/minute until the failure of specimen.
C. Water Absorption Test
Concrete cube specimens of size 150 x 150 x 150 mm size were cast and test was conducted after
curing period of 28 days. Then, the specimens were taken out from water and oven dried for 24 hours at
constant 105 oC. The oven dried weight was taken and immersed again in water, the weight was recorded at
regular intervals, till the weight becomes fully saturated. Then, the saturated weight is noted down. The
difference between saturated weight and oven dried weight gives the water absorption of the specimens.
V. Results and Discussions
A. Compressive Strength of GFRC
The values of compressive strength of all variations are given in Table 5. Fig 1 shows the variation of
compressive strength in MPa with different curing periods for all variations used. It is seen from the test results
that the compressive strength of GFRC at 7, 14 and 28 days increases initially as the percentage of replacement
of steel slag and m-sand increases and becomes maximum at a percentage around 75%. Further increase in the
percentage of steel slag and m-sand reduces the compressive strength of GFRC.
Table 5: Values of Compressive Strength in MPa
Mix Designation
CC
A0
A25
A50
A75
A100
7 days
39.2
38.5
39.7
40.3
40.9
36.1
14 days
56.1
54.7
55.4
57.8
58.5
52.3
28 days
62.4
60.2
61.4
63.5
65.1
58.2
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Compressive Strength in MPa
Second International Conference on Recent Advances in Science & Engineering-2015
70
60
50
40
7 days
30
20
14 days
10
28 days
0
CC
A0
A25
A50
A75
A100
Mix Designation
Figure 1: Variation of Compressive Strength with different curing periods
B. Split Tensile Strength of GFRC
The test results of split tensile test are as shown in Table 6. Fig 2 shows the variation of split tensile
strength with various curing periods. It can be see that the split tensile strength of GFRC at 7, 14 and 28 days
increases initially as the percentage of replacement of steel slag and m-sand increases and becomes maximum at
a percentage around 75%. Further increase in the percentage of steel slag and m-sand reduces the split tensile
strength of GFRC.
Table 6: Values of Split Tensile Strength in MPa
Split Tensile Strength in
MPa
Mix Designation
CC
A0
A25
A50
A75
A100
7 days
3.43
3.60
4.12
4.39
4.86
3.84
14 days
5.28
5.46
6.15
6.56
6.95
5.65
28 days
5.94
6.21
6.78
7.21
7.56
6.43
8
6
4
7 days
2
14 days
0
28 days
CC
A0
A25
A50
A75
A100
Mix Designation
Figure 2: Variation of Split Tensile Strength with different curing periods
C.
Water Absorption of GFRC
The test results of water absorption test are as shown in Table 7. Fig 3 shows the variation of water
absorption of different mix designations. It is seen from the water absorption test, as the percentage of
replacement of steel slag and m-sand increases, the water absorption ability of the specimen decreases and
becomes least at a percentage around 100%. So it can be said that, the GFRC at 100 % replacement level is
durable against water absorption.
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Table 7: Values of Water Absorption in percentage
Water Absorption
in %
Mix Designation
CC
A0
A25
A50
A75
A100
28 days
1.8
1.9
1.4
1.1
1.2
0.9
2
1.5
1
0.5
0
Water Absorption
Results
CC
A0
A25
A50
A75 A100
Mix Designation
Figure 3: Water Absorption for different mix designation
VI. Conclusions
On the basis of experimental study in the form of strength and durability tests by using steel slag and msand as replacement of natural coarse and fine aggregate respectively, also replacement of cement with fly ash at
constant 30% with glass fiber as reinforcement material for the production of GFRC, the following conclusions
are drawn:
1. The compressive strength of concrete at 7, 14 and 28 days increases initially as the percentage of
replacement of steel slag and m-sand increases and becomes maximum at a percentage around 75%.
Further increase in the percentage of steel slag and m-sand reduces the compressive strength of
concrete.
2. The split tensile strength of concrete at 7, 14 and 28 days increases initially as the percentage of
replacement of steel slag and m-sand increases and becomes maximum at a percentage around 75%.
Further increase in the percentage of steel slag and m-sand reduces the compressive strength of
concrete.
3. The water absorption of concrete at 28 days decreases gradually as the percentage of steel slag and msand increases and becomes least at a percentage around 100%.
4. Addition of glass fibers to concrete is seen to increase the compressive and split tensile strength of
concrete as replacement level is increased and becomes maximum at a percentage around 75%.
5. Optimum replacement level for steel slag and m-sand in place of natural coarse and fine aggregate
respectively is found to be about 75% from the consideration of strength and durability tests of GFRC.
This finding is of great importance as the natural coarse aggregate and fine aggregate is at present fast
depleting and steel slag and m-sand is suitable and viable alternative for production of GFRC as
replacement of natural aggregates.
REFERENCES
[1]
[2]
[3]
[4]
[5]
[6]
P. S. Kothai and R. Malathy, “Enhancement of concrete properties by steel slag as a partial replacement material for coarse
aggregates,” Australian Journal of Basic and Applied Sciences, 2013, pp. 278-285.
K. Chinnaraju, V. R. Ramkumar, K. Lineesh, S. Nithya and V. Sathish, “Study on concrete using steel slag as coarse aggregate
replacement and ecosand as fine aggregate replacement,” International Journal of Research in Engineering & Advanced Technology,
vol. 1, 2013.
Nagabhushana and H. Sharada Bai, “Use of crush rock powder as replacement of fine aggregate in mortar and concrete,” International
Journal of Science and Technology, vol. 4, pp. 917-922, 2011.
Gobinath. R, Vijayan. V, Sivakumar. N, Prakash. P, Suganya. S, Dhinesh. A, “Strength of concrete by partially replacing the fine
aggregate using m-sand,” Scholars Journal of Engineering and Technology, pp. 238-246, 2013.
Er. Lakhan Nagpal, Arvind Dewagan, Er. Sandeep Dhiman and Er. Sumit Kumar, “Evaluation of strength characteristics of concrete
using crushed stone dust as fine aggregate,” International Journal of Innovative Technology and Exploring Engineering, vol. 2, 2013.
Shrikant Harle and Ram Meghe, “Glass fiber reinforced concrete and its properties,” International Journal of Engineering and
Computer Science, vol. 2, pp. 3544-3547, 2013.
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[7]
Mohammed Nadeem and Arun. D. Pofale, “Experimental investigation of using slag as an alternative to normal aggregates(coarse and
fine) in concrete,” International Journal of Civil and Structural Engineering, vol. 3, 2012.
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