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					 International Journal of Civil
                                 JOURNAL OF 117- 123 © ISSN 0976
                                             and             (IJCIET),
INTERNATIONALEngineeringMarchTechnologyCIVIL IAEME – 6308 (Print),
 ISSN 0976 – 6316(Online) Volume 5, Issue 3,     (2014), pp.
                                                                       ENGINEERING
                      AND TECHNOLOGY (IJCIET)
ISSN 0976 – 6308 (Print)
ISSN 0976 – 6316(Online)                                                         IJCIET
Volume 5, Issue 3, March (2014), pp. 117-123
© IAEME: www.iaeme.com/ijciet.asp
Journal Impact Factor (2014): 7.9290 (Calculated by GISI)
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  INFLUENCE OF STEEL FIBERS AND PARTIAL REPLACEMENT OF SAND
     BY IRON ORE TAILINGS ON THE COMPRESSIVE AND SPLITTING
                 TENSILE STRENGTH OF CONCRETE

                            Ananthayya M.B.* Prema Kumar W. P.**
    *Department of Civil Engineering, NitteMeenakshi Institute of Technology, Bangalore 560 064
   **Department of Civil Engineering, Reva Institute of Technology & Management, Kattigenahalli,
                                         Bangalore 560 064




 ABSTRACT

         In this work, the effects of steel fibers and partial replacement of sand by iron ore tailings
 (IOT) on the compressive and splitting tensile strength of concrete are experimentally studied. The
 mix proportions used for concrete are 1:1.43:2.94. The percentages of steel fibers by weight of
 cement used were 0.0, 0.5, 0.7, 0.9, 1.0, 1.2, 1.4, 1.6, 1.8 and 2.0. The sand replacement (by IOT)
 percentages used were 0, 5, 10, 20, 25, 30 and 35.Compressive strength tests were conducted on 150
 mm size concrete cubes and splitting tensile strength tests on 150 mm diameter and 300 mm length
 concrete cylinders as per Bureau of Indian Standards specifications.For concrete without steel fibers,
 the compressive and splitting tensile strengths were found to vary with the percentage of IOT and the
 maximum compressive and splitting tensile strengths were obtained for 35 % of sand replacement by
 IOT. For concrete with steel fibers, the compressive and splitting tensile strengths were found to vary
 with both percentage of steel fibers and percentage of IOT. Maximum compressive and splitting
 tensile strengths were obtained for 25% of sand replacement by IOT and 1.2 % of steel fibers.

 Keywords: Concrete; Compressive Strength, Splitting Tensile Strength, Iron Ore Tailing (IOT).

 1. INTRODUCTION

          The increasing demand for heavy construction material like steel and iron and ample reserve
 of iron ore in India has resulted in the establishment of many iron ore mining companies. The residue
 left after extraction of concentrated iron from iron ore is in the form of slurry. This constitutes the
 iron ore tailing (IOT) and the same is disposed of in the vicinity of plant as waste material over
 several hectares of valuable land leading to water as well as land pollution. The production of IOT
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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print),
ISSN 0976 – 6316(Online) Volume 5, Issue 3, March (2014), pp. 117- 123 © IAEME

waste is about 18 million tonnes per annum in India. The safe disposal of large quantities of iron ore
tailing is certainly a difficult task and a matter of environmental concern.Reuse of IOT
eliminates/reduces the disposal problem.
        Many studies have been made in India and abroad on the influence of IOT on the properties
of concrete. A few are mentioned here. Huang et al. [1] have used iron ore tailings in powder form
to partially replace cement to enhance the environmental sustainability of ECC (engineered
cementitious composites). Mechanical properties and material greenness of ECC containing various
proportions of IOTs were investigated. The replacement of cement with IOTs resulted in 10–32%
reduction in energy consumption and 29–63% reduction in carbon dioxide emissions in green ECC
compared with typical ECC. Rui Ying Bai et al. [2] have assessed the alkali silica reaction (ASR) of
iron ore tailings sand using rapid mortar bar method (GB/T 14684-2001). The replacement of cement
by 30% Fly ash (FA), 50% ground granulated blast-furnace slag (GGBFS), 10% metakaolin (MK)
and replacement of sand by 15% ground iron ore tailings (GIOT) led to the ASR-expansion to below
0.10%. Compared with replacement of cement, replacement of sand led to better performance.
Furthermore, the fine particles less than 75µm in iron ore tailings sand are beneficial to the reduction
of expansion induced by ASR. Sujing Zhao et al. [3] have explored the possibility of using iron ore
tailings to replace natural aggregate to prepare UHPC under two different curing regimes. It was
found that 100% replacement of natural aggregate by the tailings significantly decreased the
workability and compressive strength of the material. However, when the replacement level was no
more than 40%, for 90 days standard cured specimens, the mechanical behavior of the tailings mixes
was comparable to that of the control mix, and for specimens that were steam cured for 2 days, the
compressive strengths of the tailings mixes decreased by less than 11% while the flexural strengths
increased by up to 8% compared to the control mix. K.G. Hiraskar and ChetanPatil[4]have utilized
the blast furnace slag from local industries to find its suitability as a coarse aggregate in concrete
making. The experimental results showed that replacing some percentage of natural aggregates by
slag aggregates causes negligible degradation in strength. The compressive strength of blast furnace
slag aggregate concrete was found to be higher than that of conventional concrete at the age of 90
days. It also reduced water absorption and porosity beyond 28 days in comparison to that of
conventional concrete with stone chips used as coarse aggregate.

2. PRESENT WORK

2.1 Materials used
        The properties of cement used are (i) normal consistency = 33%, (ii) initial setting time = 100
minutes, (iii) final setting time = 10 hours and (iv) specific gravity = 3.04. The specific gravity of
fine aggregates used is 2.671. The water absorption is 0.8%. Sieve analysis of fine aggregates shows
that the sand used in the present work falls in zone II. The specific gravity of coarse aggregate used
is 2.656. Its water absorption is zero percent. Sieve analysis of coarse aggregates shows that they are
well graded. The specific gravity of the steel fibers used is 7.8. The iron ore tailing, brought from
Kudremukh Iron Ore Company Ltd, has the physical properties given in Table 1. The chemical
composition is as given in Table 2.




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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print),
ISSN 0976 – 6316(Online) Volume 5, Issue 3, March (2014), pp. 117- 123 © IAEME




                                Figure 1: Iron ore tailings (IOT)

                              Table 1: Physical properties of IOT
                         Particle shape          Spherical
                         Density                 14.5 kN/m3
                         Specific gravity        3.21
                         Colour                  Dark tan (Brown)
                         Maximum dry density 1.71 gm/cc

                           Table 2: Chemical composition of IOT
                                 Constituent          Percentage
                                   Iron (Fe)              19
                             Silicon dioxide SiO2         69
                          Aluminium trioxide (Al2O3)       3
                           Manganese oxide (MnO)         0.20
                                Phosphorus (P)           0.04
                                  Sulphur (S)            0.08
                            Titanic dioxide (TiO2)       0.10
                             Calcium oxide (CaO)         0.10
                           Magnesium oxide (MgO)         0.16
                             Sodium oxide (Na2O)         0.06
                            Potassium oxide (K2O)        0.04
                                 Copper (Cu)             0.003
                                  Nickel (Ni)            0.002

       The mix proportions used for concrete are 1:1.43:2.94. These were designed using Bureau of
Indian Standards Method [5, 6, 7]. The percentages of steel fibers by weight of cement used were
0.0, 0.5, 0.7, 0.9, 1.0, 1.2, 1.4, 1.6, 1.8 and 2.0. The sand replacement (by IOT) percentages
considered in this work were 0, 5, 10, 20, 25, 30 and 35.
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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print),
ISSN 0976 – 6316(Online) Volume 5, Issue 3, March (2014), pp. 117- 123 © IAEME

2.2 Compressive test
        Compressive tests were conducted on 150 mm size concrete cubes in accordance with the
specifications of Bureau of Indian Standards. The test results are given in Table 3.

                          Table 3: Values of Compressive Strength
            % of      % of    Compressive      % of       % of       Compressive
            steel     IOT       Strength       steel      IOT         Strength
           fibers                (MPa)        fibers                   (MPa)
             0.0        0          31.5         0.5         0           36.5
                        5          32.0                     5           22.5
                       10          34.0                    10           24.0
                       15          34.5                    15           32.5
                       20          25.0                    20           32.0
                       25          29.0                    25           25.0
                       30          24.0                    30           21.5
                       35          36.5                    35           22.5
            0.7         0          36.0         0.9         0           31.5
                        5          23.0                     5           31.0
                       10          24.0                    10           23.0
                       15          25.0                    15           27.0
                       20          25.0                    20           28.0
                       25          30.5                    25           29.0
                       30          28.0                    30           28.0
                       35          28.0                    35           24.0
            1.0         0          28.5         1.2         0           37.0
                        5          22.0                     5           30.0
                       10          23.5                    10           31.5
                       15          23.5                    15           41.0
                       20          24.5                    20           38.0
                       25          24.0                    25           42.5
                       30          23.5                    30           29.0
                       35          24.0                    35           33.0
            1.4         0          24.0         1.6         0           26.5
                        5          22.5                     5           25.0
                       10          23.5                    10           28.5
                       15          20.0                    15           28.0
                       20          25.0                    20           27.0
                       25          29.5                    25           23.5
                       30          30.0                    30           24.5
                       35          25.0                    35           26.5
            1.8         0          20.5         2.0         0           21.0
                        5          28.0                     5           22.5
                       10          14.5                    10           24.5
                       15          20.5                    15           23.5
                       20          17.0                    20           21.5
                       25          19.0                    25           18.5
                       30          19.0                    30           21.5
                       35          23.5                    35           22.5
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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print),
ISSN 0976 – 6316(Online) Volume 5, Issue 3, March (2014), pp. 117- 123 © IAEME

2.3 Splitting Tensile Test
        Splitting tensile tests were conducted on concrete cylinders of 150 mm diameter and 300 mm
length in accordance with the specifications of Bureau of Indian Standards. The test results are given
in Table 4.

                           Table 4: Values of Splitting Tensile Strength
              % of       % of        Splitting          % of    % of IOT      Splitting
              steel      IOT          tensile           steel                  tensile
             fibers                  strength          fibers                 strength
                                      ( MPa)                                   ( MPa)
               0.0         0            2.10            0.5         0            2.17
                           5            2.17                        5            2.30
                          10            2.23                       10            2.36
                          15            2.27                       15            2.48
                          20            2.39                       20            2.56
                          25            2.51                       25            2.64
                          30            2.60                       30            2.67
                          35            2.64                       35            2.73
               0.7        0             2.29            0.9         0            2.40
                           5            2.34                        5            2.47
                          10            2.43                       10            2.56
                          15            2.53                       15            2.64
                          20            2.63                       20            2.71
                          25            2.73                       25            2.81
                          30            2.77                       30            2.87
                          35            2.70                       35            2.92
               1.0        0             2.51            1.2         0            3.36
                           5            2.63                        5            3.43
                          10            2.71                       10            3.56
                          15            2.80                       15            3.66
                          20            2.88                       20            3.70
                          25            2.95                       25            3.83
                          30            2.92                       30            3.77
                          35            2.94                       35            3.80
               1.4         0            3.31            1.6         0            2.68
                           5            3.36                        5            2.80
                          10            3.48                       10            2.92
                          15            3.52                       15            2.95
                          20            3.59                       20            3.05
                          25            3.66                       25            3.15
                          30            3.64                       30            3.11
                          35            3.63                       35            3.12
               1.8        0             2.61            2.0         0            2.71
                           5            2.67                        5            2.78
                          10            2.75                       10            2.90
                          15            2.80                       15            3.02
                          20            2.90                       20            3.09
                          25            3.09                       25            3.14
                          30            3.04                       30            3.12
                          35            3.01                       35            3.11



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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print),
ISSN 0976 – 6316(Online) Volume 5, Issue 3, March (2014), pp. 117- 123 © IAEME

3. DISCUSSION OF TEST RESULTS

3.1 Compressive test results
        From Table 3, it is seen that for concrete without steel fibers, the compressive strength varies
with the percentage of IOT. Maximum compressive strength of 36.5 MPa occurs for 35 % of sand
replacement by IOT (the compressive strength for zero percentage of sand replacement by IOT being
31.5 MPa). It is also seen from Table 3 that for concrete with steel fibers, the compressive strength
varies with both percentage of steel fibers and percentage of IOT. Maximum compressive strength of
42.5 MPa occurs for 25% of sand replacement by IOT and 1.2 % of steel fibers (the compressive
strength for zero percentage of sand replacement by IOT and zero percentage of steel fibers being
31.5 MPa). It is also seen that the percentage of sand replacement by IOT that gives maximum
compressive strength varies with the percentage of steel fibers.

3.2 Splitting tensile test results
        It is seen from Table 4 that for concrete without steel fibers, the splitting tensile strength
varies with the percentage of IOT. Maximum splitting tensile strength of 2.64 MPa occurs for 35 %
of sand replacement by IOT (the splitting tensile strength for zero percentage of sand replacement by
IOT being 2.10 MPa). It is also seen from Table 4 that for concrete with steel fibers, the splitting
tensile strength varies with both percentage of steel fibers and percentage of IOT. Maximum splitting
tensile strength of MPa occurs for 25% of sand replacement by IOT and 1.2 % of steel fibers (the
splitting tensile strength for zero percentage of sand replacement by IOT and zero percentage of steel
fibers being 2.10 MPa). It is also seen that the percentage of sand replacement by IOT that gives
maximum splitting tensile strength varies with the percentage of steel fibers and lies in the range of
25 to 35%.

4. CONCLUSIONS

The following conclusions are made based on the above experimental study.
   • For concrete without steel fibers, the compressive strength varies with the percentage of IOT.
       Maximum compressive strength of 36.5 MPa was obtained for 35 % of sand replacement by
       IOT (the compressive strength for zero percentage of sand replacement by IOT being 31.5
       MPa).
   • For concrete with steel fibers, the compressive strength varies with both percentage of steel
       fibers and percentage of IOT. Maximum compressive strength of 42.5 MPa was obtained for
       25% of sand replacement by IOT and 1.2 % of steel fibers (the compressive strength for zero
       percentage of sand replacement by IOT and zero percentage of steel fibers being 31.5 MPa).
   • The percentage of sand replacement by IOT that gives maximum compressive strength
       varieswith the percentage of steel fibers.
   • For concrete without steel fibers, the splitting tensile strength varies with the percentage of
       IOT. Maximum splitting tensile strength of 2.64 MPa was obtained for 35 % of sand
       replacement by IOT (the splitting tensile strength for zero percentage of sand replacement by
       IOT being 2.10 MPa).
   • For concrete with steel fibers, the splitting tensile strength varies with both percentage of
       steel fibers and percentage of IOT. Maximum splitting tensile strength of MPa was obtained
       for 25% of sand replacement by IOT and 1.2 % of steel fibers (the splitting tensile strength
       for zero percentage of sand replacement by IOT and zero percentage of steel fibers being 2.10
       MPa).
   • The percentage of sand replacement by IOT that gives maximum splitting tensile strength
       varies with the percentage of steel fibers and lies in the range of 25 to 35%.

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print),
ISSN 0976 – 6316(Online) Volume 5, Issue 3, March (2014), pp. 117- 123 © IAEME

REFERENCES

 1. Huang, X., Ranade, R., and Li, V. (2013), “Feasibility Study of Developing Green ECC Using
     Iron Ore Tailings Powder as Cement Replacement”, J.Mater.Civi.Eng., 25(7), 923-931.
 2. Rui Ying Bai et al., (2011), Advanced Materials Research, pp. 295-297, 594.
 3. Sujing Zhao, JunjiangFanandWei Sun(2014), “Utilization of iron ore tailings as fine aggregate
     in ultra-high performance concrete”, Construction and Building Materials, 50, pp. 540-548.
 4. K.G. Hiraskar and ChetanPatil (2013), “Use of Blast Furnace Slag Aggregate in Concrete”,
     International Journal of Scientific & Engineering Research, Volume 4, Issue 5, pp. 95-98.
 5. Recommended guidelines for concrete mix design, IS: 10262-2009, Bureau of Indian
     Standards, New Delhi.
 6. Handbook on concrete mixes, SP 23-1982, Bureau of Indian Standards, New Delhi.
 7. N. Krishna Raju, Design of concrete mixes, 4th Edition, CBS Publishers, New Delhi.
 8. Methods of tests for strength of concrete, IS: 516-1959, Bureau of Indian Standards, New
     Delhi.
 9. Ghassan Subhi Jameel, “Study the Effect of Addition of Wast Plastic on Compressive and
     Tensile Strengths of Structural Lightweight Concrete Containing Broken Bricks as Acoarse
     Aggregate”, International Journal of Civil Engineering & Technology (IJCIET), Volume 4,
     Issue 2, 2013, pp. 415 - 432, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316.
 10. Riyaz Khan and Prof.S.B.Shinde, “Effect of Unprocessed Steel Slag on the Strength of
     Concrete When Used as Fine Aggregate”, International Journal of Civil Engineering &
     Technology (IJCIET), Volume 4, Issue 2, 2013, pp. 231 - 239, ISSN Print: 0976 – 6308,
     ISSN Online: 0976 – 6316.




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