International Journal of Scientific & Engineering Research, Volume 5, Issue 9, September-2014 805
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Effect of Replacement of Cement by Red mud on the Properties of Concrete
Sunitha M.Pujar, Dr.K.B.Prakash
Abstract— Rapid industrialization leads to the maximum discharge of waste products which in turn causes the environmental hazards. These wastes can be a substitute for conventional material, when utilized in a best way. Red mud is a waste generated by the aluminum industry (an average of 4 million tons/year) in a Bayer’s process and their disposal is a major problem for these industries because of the complex physio-chemical properties of waste products which are highly caustic and causes ground water contamination, leading to health hazards. To overcome this problem it is very much essential to utilize the industrial waste materials and by-products generated, in manufacturing of cement and in concrete construction. Here in this work
by taking the cementitious behavior of industrial wastes into account, an experiment was carried out to partially replace the portland cement by red mud in concrete for variable percentages and also there effects on the strength of the concrete.
One main objective of this work is to study the effects of red mud on properties of concrete of M30 grade. The red mud percentage for replacement of cement is varied as 0%, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18% & 20%.
Index Terms— Redmud, Workability, Strength Properties, Soroptivity
—————————— ——————————
R ed mud is a by-product of the Bayer process,
which is used for the production of alumina from
bauxite. Washed and crushed bauxite is treated with a
solution of hydroxide at an elevated temperature and
pressure. This process brings all the recoverable alu-
mina from bauxite into solution and the residue
known as red mud. For each part of alumina pro-
duced by this process, about one part of red mud is
generally discarded as a waste. In Western countries,
about 35 million tons of red mud is produced yearly.
Due to its caustic nature, it poses a major environ-
mental problem. Disposal of this waste was the first
major problem encountered by the alumina industry
after the adoption of the Bayer process. These at-
tempts were based mainly on the use of red mud as a
partial substitute for clay in the production of bricks
and other ceramic products. So far, the various uses of
red mud developed includes, tiles, glazes and red
mud–polymer composites panels as wood substitute,
iron rich cement etc. Fundamental studies carried out
for the extraction of iron oxide or titanium oxide are
reported to be economically unsustainable and there-
fore red mud as such has been used for various appli-
cations. Red mud has also been used for catalytic hy-
dro-de chlorination of tetrachloroethylene for the
treatment of gold ores, in making silicate bonded un
sintered ceramics, heavy clay products, sintered ce-
ramics etc. In view of above, there is a great scope to
evolve innovative strategy and to develop novel func-
tional applications of red mud based materials, for
effective utilization of red mud. The application of
radiation technology in medicine, agriculture, nuclear
reactor and other industries is increasing day by day
all over the world.
Red mud has a reddish brown color and a superfine, fine particle-size distribution as it’s physical charac- teristics, as well as alkalis, iron oxides and hydrox- ides, aluminum hydroxides, calcium carbonate, tita- nia, and silica in its chemical composition. The super- fine particles characteristic of red mud makes this a promising admixture for mortar and concrete .Clay minerals into pozzolanic admixtures that are able to consume the calcium hydroxide produced by cement hydration.
Red mud is considered due to its high pH varies Be- tween 10 to 14 and discharged as high alkaline slurry. Red mud contains six major oxides named CaO, SiO2, Fe2O3, Al2O3, TiO2 and Na2O and small quantities of numerous minor elements. And few of above men- tioned oxides are present in cement also. Hence red mud is called as a cementatious material. The below table including a composition of percentage of oxides present in a red mud, the estimated chemical compo- sition of red mud based on literature survey is shown in Table 1
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Ingredient | Oxides | % in RM (Un- washed ) | % in OPC | % in RM (washed) |
Lime | CaO | 3.00 | 62.0 | 3.50 |
Silica | SiO2 | 8.5 | 22.0 | 9 |
Aluminium | Al2O3 | 20.00 | 5.0 | 22 |
Iron oxide | Fe2O3 | 42.00 | 3.0 | 47 |
Sodium oxide | Na2O | 4.5 | - | 3.5 |
Titanium | TiO2 | 10.4 | - | 12.4 |
Alkalies | - | - | 01 | - |
LOI | - | 14.00 | - | 19.00 |
Neutralization of red mud will help to reduce the en- vironmental impact caused due to its storage and also lessen significantly the on going management of the deposits after closure. It will also open opportunities for re-use of the residue which to date have been pre- vented because of the high pH. Neutralization of red mud to pH around 8.0 is optimal because the chemi- cally adsorbed Na is released, alkaline buffer minerals are neutralized and toxic metals are insoluble at this pH. Efforts are being carried out to study the amelio- ration of red mud by possibly incorporating a pH- reduction processing step during disposal of red mud and include studies on processes based on acid neu- tralization, CO2 treatment, seawater neutralization, bioleaching and sintering.
The binder materials used in mixes were ordinary
Portland cement (OPC) 43 grade conforming to IS:
8112 – 1989, Red mud used for the replacement of
cement is brought from aluminum industry obtained
by Bayer ’s process, HINDALCO, Belgaum, Washed
Red mud and Unwashed Red mud.
Locally available river sand belonging to zone II of IS
383-1970 was used. Locally available crushed aggre-
gates confirming to IS 383-1970 was used. Water fit for
drinking and commercially available high perfor-
mance super plasticizing admixture, Conplast SP430;
conforming to ASTM C 494 (1992) were used in this experimentation.
Cement, sand and aggregate were taken in mix pro-
portion 1:1.64:2.74 which correspond to M30 grade of
concrete. Cement is replaced with red mud (as 0%,
2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18% & 20%). All
the ingredients were dry mixed homogeneously. To
this dry mix, required quantity of water was added
(W/C= 0.45) and the entire mix was again homogene-
ously mixed. This wet concrete was poured into the
moulds which was compacted through hand compac-
tion in three layers and then kept into the vibrator for
compaction. After the compaction, the specimens
were given smooth finishes and were covered with
gunny bags. After 24 hours, the specimens were
demoulded and transferred to curing tanks where in
they were allowed to cure for 28 days.
Workability: Slump test, compaction factor test. Mechanical strength characteristics: A.Compressive strength
B.Split tensile strength C.Flexure strength D.Shear strength E.Water absorption F.Sorptivity test
To study the effects on mechanical properties follow- ing test are conducted.
The mix design procedure adopted to obtain a M30 grade concrete is in accordance with IS 10262- 2009. The mix proportion for M 30 grade concrete arrived at is
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Following tables give the compressive strength, split tensile strength, flexural strength, shear strength and impact strength test results for concrete .The variation in strength is depicted in the form of graphs.
Percentage replacement of cement by red mud | Slump (mm) values | |
Percentage replacement of cement by red mud | Washed red mud | Unwashed red mud |
0% | 72 | 72 |
2% | 75 | 75 |
4% | 77 | 74 |
6% | 78 | 74 |
8% | 79 | 73 |
10% | 74 | 72 |
12% | 72 | 70 |
14% | 70 | 67 |
16% | 69 | 65 |
18% | 68 | 64 |
20% | 65 | 62 |
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Per- cent age re- plac eme nt of ce- ment by red mud | Com- pres- sive strengt h of con- crete pro- duced by replac- ing ce- ment by washe d red mud (MPa) | Per- centag e in- crease or de- crease of com- pres- sive strengt h w.r.t refer- ence mix | Com- pres- sive strengt h of con- crete pro- duced by replac- ing ce- ment by un- washe d red mud (MPa) | Per- centag e in- crease or de- crease of com- pres- sive strengt h w.r.t refer- ence mix | Per- centa ge in- creas e of com- pres- sive stren gth for con- crete pro- duce d by wash ed red mud |
0% (Ref er- ence mix) | 45.04 | - | 45.04 | - | 0.00 |
2% | 51.11 | +13.48 | 49.78 | +10.52 | +2.67 |
4% | 52.00 | +15.45 | 48.59 | +7.88 | +7.02 |
6% | 53.19 | +18.08 | 45.48 | +0.98 | +16.9 4 |
8% | 55.85 | +24.00 | 42.07 | -6.59 | +32.7 6 |
10% | 48.89 | +8.55 | 39.56 | -12.17 | +23.5 8 |
12% | 48.15 | +6.90 | 38.96 | -13.50 | +23.5 8 |
14% | 46.22 | +2.62 | 37.04 | -17.76 | +24.7 9 |
16% | 44.44 | -1.32 | 35.85 | -20.40 | +23.9 7 |
18% | 42.81 | -4.94 | 35.7 | -20.74 | +19.9 3 |
20% | 40.00 | -11.19 | 34.96 | -22.38 | +14.4 2 |
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Per- cent age re- plac eme nt of ce- ment by red mud | Shear stren gth of con- crete pro- duced by replac plac- ing ce- ment by wash ed red mud (MPa) | Per- centag e in- crease or de- crease of shear strengt h w.r.t refer- ence mix | She ar stren gth of con- crete pro- duce d by re- plac- ing ce- ment by un- was hed red mud (MP a) | Per- centag e in- crease or de- crease of shear strengt h w.r.t refer- ence mix | Per- centag e in- crease of shear strengt h for con- crete pro- duced by washe d red mud |
0% (Ref er- ence mix) | 5.00 | - | 5.00 | - | 0.00 |
2% | 7.04 | +40.80 | 6.48 | +29.60 | +8.64 |
4% | 7.22 | +44.40 | 6.30 | +26.00 | +14.60 |
6% | 7.41 | +48.20 | 6.11 | +22.20 | +21.28 |
8% | 7.78 | +55.60 | 5.93 | +18.60 | +31.20 |
10% | 6.48 | +29.60 | 5.56 | +11.20 | +16.55 |
12% | 6.30 | +26.00 | 5.19 | +3.80 | +21.39 |
14% | 5.56 | +11.20 | 4.63 | -7.40 | +20.09 |
16% | 5.00 | 0.00 | 3.70 | -26.00 | +35.14 |
18% | 4.81 | -3.80 | 2.96 | -40.80 | +62.50 |
20% | 3.70 | -26.00 | 2.59 | -48.20 | +42.86 |
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Following conclusions can be drawn based on the studies made
1. Workability of concrete is higher at a cement re- placement level of 8% by washed red mud. Be- yond this replacement level workability decreas- es drastically.
2. Workability of concrete is higher at a cement replacement level of 2% by unwashed red mud. Beyond this replacement level workability de- creases drastically.
3. Workability of concrete produced by replacing cement by washed red mud is higher as com- pared to concrete produced by unwashed red mud.
4. Compressive strength of concrete produced by
replacing cement by washed red mud goes on increasing upto 8% replacement of cement by washed red mud and reaches peak at 8%.
5. Compressive strength produced by replacing cement by unwashed red mud goes on increas- ing upto 2% replacement and reaches peak at
2%.
6. Compressive strength of concrete produced by replacing cement by washed red mud is higher as compared to concrete produced by unwashed red mud.
7. Split tensile strength of concrete produced by replacing cement washed red mud goes on in- creasing upto 8% replacement and reaches peak at 8%.
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8. Split tensile strength produced by replacing ce-
ment by unwashed red mud goes on increasing upto 2% replacement and reaches peak at 2%.
9. Split tensile strength of concrete produced by replacing cement by washed red mud is higher as compared to concrete produced by unwashed red mud.
10. Flexural strength of concrete produced by re-
placing cement by washed red mud goes on in- creasing upto 8% replacement and reaches peak at 8%.
11. Flexural strength of concrete produced by re- placing cement by unwashed red mud goes on increasing upto 2% replacement of cement and reaches peak at 2%.
12. Flexural strength of concrete produced by re- placing cement by washed red mud is higher as compared to concrete produced by unwashed red mud.
13. Shear strength of concrete produced by replac- ing cement by washed red mud goes on increas- ing upto 8% replacement and reaches peak at
8%.
14. Shear strength of concrete produced by replac- ing cement by unwashed red mud goes on in- creasing upto 2% replacement and reaches peak at 2%.
15. Shear strength of concrete produced by replac-
ing cement by washed red mud is higher as compared to concrete produced by unwashed red mud.
16. Water absorption of concrete produced by re-
placing cement by washed red mud goes on de-
creasing upto 8% replacement and reaches low-
est value at 8%.
17. Water absorption produced by replacing cement by unwashed red mud goes on decreasing upto
2% replacement and reaches lowest value at 2%.
18. Water absorption of concrete produced by re- placing washed red mud is higher as compared to concrete produced by unwashed red mud.
19. Sorptivity of concrete produced by replacing cement by washed red mud goes on decreasing upto 8% replacement and reaches lowest value at 8%.
20. Sorptivity produced by replacing unwashed red mud goes on decreasing upto 2% replacement and reaches lowest value at 2%.
21. Sorptivity of concrete produced by replacing washed red mud is higher as compared to con- crete produced by unwashed red mud.
1. Junior N. Gordon, Willard R. Pinnock, Marcia M. Moore “A preliminary investigation of strength development in Jamaican red mud composites”, Cement and Concrete Composites, Volume 18, Issue 6, 1996, pp
371-379.
2. Maneesh Singh, Upadhaya. S.N, Prasad.
P.M. “Preparation of iron rich cements us- ing red mud”, Cement and Concrete Re- search, Vol. 27, 1997, pp 1037-1046.
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ISSN 2229-5518
Research, Vol. 27, pp1513-1522, 1997
5. Zhihua Pan, Dongxu Li, Jian Yu, Nanru Yang “Properties and microstructure of the hardened alkali-activated red mud–slag cementitious material” ,Cement and Con- crete Research, Volume 33, Issue 9, Sep- tember 2003, pp 1437-1441.
6. Tim Newson, Tom Dyer, Chris Adam and Sandra Sharp, (2006) in their paper entitled, “Effect of structure on the geotechnical properties of bauxite residue”, ASCE, pp
1061-1090.
1951.
Cooling, P. Y. L. Kong and Mahfooz Soomro (2007) in their paper entitled “Comparison of physical properties between treated and untreated bauxite residue mud”, ASCE, pp 1061-1561
C. “Neutralization of red mud using mine water” Conference on Emerging Trends in Mining and Allied Industries, NIT, Rourkela,
2008.
927–932, 2009.
13. Daniel Véras Ribeiroa , Joao António Labrinchab , Marcio Raymundo Morellia (2010) in their paper entitled, “Use of red mud as addition for portland cement mor- tars”, Journal of material science and engi- neering, Volume 4
M.B, Biyanto. T.R , “ Sidoarjo mud: A po- tential cement replacement material” Civil Engineering Dimension, Vol. 12, No. 1, March 2010, 18-22.
16. Xiaoming Liu, Na Zhang, Henghu Sun, Jixiu Zhang, Longtu Li “Structural investigation relating to the cementitious activity of bauxite residue Red mud” Cement and Concrete Research, Volume 41, Issue 8, Au- gust 2011, pp 847-853.
V. A. “Utilization of industrial waste (Neu- tralized red mud) in concrete” International Journal of Advances in Science and Tech- nology, Vol. 3, pp 114-134, 2011.
cha, Márcio Raymundo Morelli “Chloride dif-
IJSER © 2014 http://www.ijser.org
International Journal of Scientific & Engineering Research, Volume 5, Issue 9, September-2014 814
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19. Na Zhang, Xiaoming Liu, Henghu Sun, Long- tu Li “Pozzolanic behaviour of compound- activated red mud-coal gangue mixture” Cement and Concrete Research, Volume 41, Issue 3, March 2011, Pages 270-278.
Title no 78-12, pp 141-146
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