STRENGTH AND DURABILITY CHARACTERISTICS OF …

IJMTES | International Journal of Modern Trends in Engineering and Science ISSN: 2348-3121

STRENGTH AND DURABILITY CHARACTERISTICS OF CONCRETE USING

METAKAOLIN AND FOUNDRY SAND R.Lavanya¹,R.Venkatakrishnaiah²

1(Dept of Civil Engg, PG Student, Adhiparasakthi engineering college, Melmaruvathur -603319, [email protected]) 2(Dept of Civil Engg, Associate Professor, Adhiparasakthi engg. college, Melmaruvathur -603319, [email protected])

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Abstract—In the last few years various research and modification has been done to produce concrete which has the desired properties. Concrete is one of the most common materials used in the construction field. The current area of research in the concrete was introducing foundry sand and metakaolin in the ordinary concrete. Generation of waste foundry sand as byproduct of the metal casting industries causes environmental problems because of its proper disposal. Thus its usage in building materials, construction and in other fields is essential for reduction of environmental problems. This research was carried out to produce an eco – friendly concrete. This paper demonstrates the possible use of waste foundry sand and metakaolin as a partial replacement by fine aggregate and cement. An experimental investigation was carried out on concrete containing waste foundry sand in the range of (0%, 10%, 20%, 30%,and 40%) by the weight for M30 grade of concrete. Metakaolin which is obtained by the calcinations of pure or refined kaolinitic clay at a temperature of between 6500C and 8500C, followed by grinding to achieve a fineness of 700-900 /kg exhibits high pozzolanity. When used in concrete it will fill the void space between cement particles resulting in a more impermeable concrete. The metakaolin were replaced in the level of (5%, 10%, 15%, and 20%) by the weight of cement. Material was tested and compared with conventional concrete in terms of strength and durability. These tests were carried out on standard cube , cylinder and beam for 7 and 14 and 28 days to determine the properties of concrete. The aim of this research was to know the behavior and strength and durability properties of concrete after addition of foundry sand and metakaolin in different proportion by tests like compressive strength by cube specimen , split tensile by cylindrical specimen and flexural strength by beam model. The research was a resource for exploring the potential use of foundry sand and metakaolin as an alternative to virgin raw materials.

Keywords— foundry sand, metakaolin , compressive strength , split tensile strength, flexural strength. _________________________________________________________________________________________________________________

1. INTRODUCTION The current area of research in the concrete is introducing foundry sand in the ordinary concrete. Foundry sand is high quality silica sand with uniform physical characteristics. It is a byproduct of ferrous and nonferrous metal casting industries, where sand has been used for centuries as a molding material because of its thermal conductivity. It is a byproduct from the production of both ferrous and nonferrous metal castings. Indian foundries produce approximately 1.71 million tons of waste foundry sand each year (metal world, 2006). The considerable disposal expense has made the current practice of WFS disposal in landfills less favorable. Besides the financial burden to the foundries, land – filling WFS also make them liable for future environmental costs, remediation problems and regulation restrictions. This issue is increasingly addressed by alternate options of reusing WFS beneficially. Beneficial reuses of WFS in variety of application related to infrastructure engineering and rehabilitation works. Unlike industrial by products such as fly ash , silica fume and metakaolin. The particle size of metakaolin is generally less than 2 µm, which is significantly smaller than that of cement particles. Moreover , the use of metakaolin in concrete in its present from is relatively a new concept. Recent works have shown that the inclusion of metakaolin greatly influenced the mechanical and durability properties of concrete. It has also been demonstrated that concrete mixture incorporating high – reactivity metakaolin gave comparable performance to silica fume mixtures in terms of strength, permeability, and chemical resistance. The utilization of this material is also

eco – friendly since it helps in reducing the emission to the atmosphere by the minimization of the Portland cement (pc) consumption. Some of the researchers have reported the possible use of foundry sand in different civil engineering applications. These alternate applications offer cost savings for both foundries and user industries and environmental benefits at the local and national level.

2. LITERATURE REVIEW Raft siddique et al. (2008) presented the results of an experimental investigation carried out to evaluate the mechanical properties of concrete mixtures in which fine aggregate (regular sand) was partially replaced with used foundry sand (UFS). Fine aggregate was replaced with three percentages (10%, 20%,and 30%) of UFS by weight. Tests were performed for the properties of fresh concrete compressive strength , splitting tensile strength, flexural strength , and modulus of elasticity were determined at 28,56,and 365 days. Test result indicated a marginal increase in the strength properties of plain concrete by the inclusion of UFS as partial replacement of fine aggregate (sand) and that can be effectively used in making good quality concrete and construction materials. Bai et al.(2003) used neural networks to predict workability of concrete incorporating metakaolin and fly ash. The prediction reflected the effect of graduated variation in pozzolanic replacement inPortland cement up to 15% MK and 40% FA. The results showed that the models are reliable and accurate and illustrate how neural networks can be used to beneficially predict the workability parameters of slump, compacting factor and vebe time across a wide range of PC-

Volume: 03 Issue: 07 2016 www.ijmtes.com 143


FA-MK compositions. On the basis of the models developed, effects of MK and FA on workability were analyzed and ISO-slump maps were plotted for w/b 0.25, 0.4 and 0.5. Through this, it is possible for designer to produce mixtures with various blend compositions. Rafat siddique and EI- Hadj kadri (2011) dealt with the effect of foundry sand (FS) and metakaolin (MK) on the near surface characteristics of concrete. A control concrete having cement content 450 kg/m and w/c of 0.45 was designed. Cement was replaced with three percentages (5%,10% and 15%) of metakaolin weight, and fine aggregate were replaced with 20% foundry sand. Tests were conducted for initial surface absorption,sorptivity, water absorption and compressive strength at the ages of 53, 56, and 84 days. H. Merve Basar and Nuran Deveci Aksoy (2012) studied the potential re- use of weight and solidification /stabilization (s/s) process was applied to all concrete mixtures. Three aspects were investigated for qualification of WFS – based –RMC, i.e.the waste foundry sand (WFS) in ready – mixed concrete (RMC) production. Regular sand was replaced with five percentage (0%, 10%,20%, 30%, and 40%) of WFS by mechanical, leaching and micro – structural properties. Various tests for the mechanical and physical performance of the solidification products were carried out, and the result indicated the addition of WFS as partial replacement of sand reduced the strength performance and density and also increased the water absorption ratio of the concrete mixtures. Nevertheless , the concrete having 20% WFS exhibited almost similar result with the control one. The findings of this research suggest that WFS can be effectively utilized in making good quality RMC as a partial replacement of fine aggregate with no adverse mechanical , environmental and micro – structural impacts; however , the partial replacement should not exceed 20%. Gurpreet singh and rafat siddique (2011) carried out an experimental investigation to evaluate the strength and durability properties to mixtures, in which natural sand was partial replaced with (WFS). Natural sand was five percentage (0%,5%, 10%, 15%, 20%) of WFS by weight. Compressive test and splitting tensile strength test were carried out to evaluate the strength properties of concrete at the age of 7,28, and 91 days.Test result indicates a marginal increase in strength properties of plain concrete by inclusion of WFS as a partial replacement of fine aggregate.

3. MATERIAL PROPERTIES Physical characteristics of waste foundry sand: waste foundry sand is typically sub angular to round shape. After being used in the foundry process, a significant number of sand agglomerations from. When these are broken down, the shape of individual sand grains is apparent. Green sands are typically black , or gray , not green chemically bonded sand is typically a medium tan or off- white in colour.

Fig 1: foundry sand

Physical properties: typical physical properties of waste foundry sand from green sand systems are given in table 1. Table 1: physical properties of waste foundry sand (WFS) and natural sand (BIS: 383- 1970)

Properties Normal sand Foundry sand Specific gravity 2.68 2.18 Absorption (%) 1.2 0.42 Moisture content (%) 0.16 0.11 Fineness modulus 2.64 1.89 Fine particles less than 0.07mm (%)

0.5 0.8

Chemical composition: chemical composition of the waste foundry sand relates directly to the metal moulded at the foundry. This determines the binder that was used, as well as the combustible additives. Typically , there is some variation in the foundry sand chemical composition from foundry to foundry. Sands produced by a single foundry ,however, will not likely show significant variation over time. The foundry and can impact its performance. Waste foundry sand consists primarily of silica sand , coated with a thin flim of burnt carbon, residual binder (bentonite, coal, resins) and dust. Silica sand is hydrophilic and consequently attracts water to its surface. This property could lead to moisture – accelerated damage. Waste foundry sand economics:The success of using waste foundry foundry sand depends upon economics. The bottom line issues are cost, availability of the waste foundry and availability of similar natural aggregates in the region. If these issues can be successfully resolved , the competitiveness of using waste foundry sand will increase for the foundries and for the end users of the sand. This is true of any recycled material. Waste foundry sand engineering characteristics: since waste foundry sand has nearly all the properties of natural or manufactured sands, it can normally be used as a sand replacement. It can be used directly as a fill material in embankments. It can be used as a sand replacement in hot mix asphalt, flowable fills, and Portland cement concrete. it can also be bended with either coarse or fine aggregates and used as a road base or sub base material. Properties of metakaolin : metakaolin (MK) is available in dry powder from and is procured from welcome chemicals in Pondicherry. It is available in 40kg bags.



Fig 2: metakaolin The physical properties of metakaolin shown in the table 2. Table 2: The physical properties of metakaolin

S.NO PROPERTIES RESULT 1 Brightness 76% 2 Bulk density 308 gm/l 3 Oil absorption 56.9 gm/100 gm 4 Moisture content 0.23% 5 Residue on 400 µm 0.6%

4. EXPERIMENTAL INVESTIGATION Cement : ordinary Portland cement (ultra tech cement) of 53 grade conforming to IS: 12269 – 1987 was used. It was tested for its physical properties as per IS 4031 (part II) – 1988 and chemical properties as per IS: 12269 .fineness of cement by hand sieving method = 10%. Properties of cement shown in the table 3. Table 3: properties of cement

S.NO PROPERTY VALUE 1 Normal consistency 26% 2 Initial setting time 40 minutes 3 Final setting time 8 hours 4 Specific gravity 3.14 5 Fineness of cement 3% Fine aggregate: The locally available river sand was used as fine aggregate in the present investigation. The sand was free from clayey matter , salt and organic impurities. The sand was tested for various properties like specific gravity , bulk density etc., and in accordance with IS 2386 – 1963. Properties of fine aggregate shown in the table 4. Table 4: properties of fine aggregate

S.NO PROPERTY VALUE 1 Specific gravity 2.62 2 Bulking absorption 1% 3 Bulking of sand 11.9% 4 Fineness modulus 2.565 Coarse aggregate: machine crushed angular granite metal of 20 mm nominal size from the local source was used as coarse aggregate. It was free from impurities such as dust, clay particles and organic matter etc. the physical properties

of coarse aggregate were investigated in accordance with IS 2386 – 1963. Properties of coarse shown in the table 5. Table 5: properties of coarse aggregate

S.NO PROPERTY VALUE 1 Specific gravity 2.6 2 Water absorption 0.50% 3 Fineness modulus 2.29 4 Crushing value 12.42% 5 Impact value 11.2% 6 Flakiness index 35.85% 7 Elongation index 45.45% Water : locally available water used for mixing and curing which is potable and free from injurious amount of oils, acids, alkalis , salt, sugar, organic material or other substance that may be deleterious to concrete or steel. Mixes:The present experiment is carried out to investigate strength properties of concrete mixes of grade M30 in which fine aggregate (river sand) is to be partially replaced with waste foundry sand. Fine aggregate will be replaced with four percentages (10% , 20% , 30% , 40%) of WFS by weight. Cement is to be partially replaced with metakaolin. Cement will be replaced with four percentages (5%, 10%,15%,20%). Mixing,casting,curing, and testing:The required number of specimens for various combinations were cast. Continuous curing was maintained up to age of 7,28,56 days. Mixing, casting, curing, testing were carried out as per the specification.

5. RESULT AND DISCUSSION The study was conducted to find out the influence of waste foundry sand and metakaolin on strength and durability properties of concrete. The effects of following parameters were studied. Compressive strength, split tensile strength, flexural strength at various percentage replacement of fine aggregate with foundry sand and cement with metakaolin on concrete. Compressive strength , split tensile strength , flexural strength of concrete increases with increase of waste foundry sand up to 40% and metakaolin 15%. It was the maximum replacement level. Use of foundry sand in concrete reduce the production of waste through the metal casting industries. i.e it’s an eco- friendly building material. Application of this study leads to develop in construction sector and innovative building material. Compressive strength: cube specimens were tested for compression and ultimate compressive strength was determined from failure load measured using compression testing machine. The average value of compressive strength of 3 specimens for each category at the age of 7 days, 14 days and 28 days are tabulated in the table 6. Table 6: compressive strength of specimen

SPECIMEN 7 DAYS 14 DAYS 28 DAYS 10% FS & 5% MK

28.5 36.0 41.0

20% FS & 10% MK

28.88 36.44 44

30% FS & 15% MK

35.5 38.5 45.11

40% FS & 20% MK

38 39.4 42.5



There is a considerable improvement in the compressive strength of concrete with inclusion and increase in the percentage of waste foundry sand up to 40%. Increase in the percentage of metakaolin up to 20% the concrete showed marginal decrease in strength. It is observed that the compressive strength increased with increasing age of curing. The maximum compressive strength was achieved by 15% replacement cement with metakaolin . Split tensile strength: cylinder specimens were tested for splitting tensile strength. The test was carried out according to IS: 5816 – 1970(10). In this test compressive line loads were applied along a vertical symmetrical plane, which causes splitting of specimen. The average values of 3 specimens for each category at the ages of 28 &56 days are tabulated in the table 4. The increase in the splitting tensile strength of various concrete mixtures over plain concrete is also tabulated in table 7. Table 7: Split tensile strength of specimen

SPECIMEN 7 DAYS 14 DAYS 28 DAYS 10% FS & 5% MK

6.05 6.3 6.35

20% FS & 10% MK

6.68 6.84 6.9

30% FS & 15% MK

7.0 7.32 7.64

40% FS & 20% MK

7.1 6.9 6.82

6. ACKNOWLEDGEMENT: I would like to thank professors A.krishnamoorthi and T.D.Ramadasan for their comments on the earlier drafts on the paper. REFERENCES

[1] Rafat siddique, Geert de Schutter, Albert Noumowe, (2008), “Effect Of Used – Foundry Sand On The Mechanical Properties Of Concrete”, Construction And Building Materials, vol.23, pp 976 – 980.

[2] Yogesh Aggarwal , Paratibha Aggarwal, Rafat Siddique , EI – Hadi kadri and rachid bennacer, (2010), “Strength , Durability , And Micro – Structural Properties Of Concrete Made With Used – Foundry Sand (UFS)” Construction And Building Materials, Vol.25, pp 1916 – 1925.

[3] Gupreet Singh And Rafat Siddique , (2011), “Effect Of Waste Foundry Sand (WFS) As Partial Replacement Of Sand On Strength, Ultrasonic Pulse Velocity And Permeability Of Concrete”, Construction And Building Materials, vol.26, pp 416 – 422.

[4] khatib JM, EII is DJ,.(2001), “Mechanical Properties Of Concrete Containing Foundry Sand”. ACI Special Publication (sp – 200), American Concrete Institute; pp. 733 – 748.

[5] siddique R., Gupta R, kaur i., (2007), “Effect Of Spent Foundry Sand As Partial Replacement Of Fine Aggregate On The Properties Of Concrete”. In: 22 and International Conference On Solid Waste Technology And Management , widener University, Philadelphia, USA.

[6] Gurdeep Kaur, Anita Rajor And Rafat Siddique, (2011), “Properties Of Concrete Containing Fungal Treated Waste Foundry Sand”, Construction and Building Materials, vol. 29, PP 82 – 87.

[7] Dunster, A.M., Parsonage, J.R., Thomas , M.J.K., (1999). “Pozzolonic Reaction Of Metakaolinite Its Effects On Portland Cement Hydration”. Journal Of Material Science. Pp 1345 – 1350.

[8] American foundrymen’s society (1991). “Alternative utilization of foundry waste sand”. Final report (phase I) prepared by American foundry men’s society.


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