INTERNATIONAL JOURNAL OF CIVIL ENGINEERING. International Journal of Civil Engineering and Technology (IJCIET), ISSN (Print),

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1 INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND TECHNOLOGY (IJCIET) ISSN (Print) ISSN (Online) Volume 5, Issue 6, June (2014), pp IAEME: Journal Impact Factor (2014): (Calculated by GISI) IJCIET IAEME STUDIES ON UNPROCESSED STONE DUST AS FINE AGGREGATE IN MAKING CONCRETE Er. S. Thirougnaname 1, S. Segaran 2 1 M.Tech., MIE., MISTE., FIAH., MIWWA., AMISE., MIT Arb., MICI., Project Engineer, Pondicherry Tourism Development Corporation, Puducherry, India. 2 M.Tech., Civil Engineer, Puducherry, India ABSTRACT Experimental investigation was carried out to establish the feasibility of unprocessed stone dust as fine aggregate in place of river sand which has become a scarcity now-a-days, by casting cube and determining the compressive strength for the two grades of concrete M15 and M20. The result obtained are compared with conventional concrete. It is concluded that compressive strength at 28 days of unprocessed stone dust used as fine aggregate in concrete gives 35% higher strength for M15 and 4% for M20 grade concrete when compared to the reference concrete. The split tensile strength of unprocessed stone dust concrete is 2.98 N/mm 2 and 3.25 N/mm 2 for M15 and M20 grade respectively where as the reference concrete is 2.58 N/mm 2 and 3.18 N/mm 2 only. This investigation has demonstrated that the unprocessed stone dust is equally good as fine aggregate like river sand and hence can be used in making concrete. Keywords: Concrete, Stone Dust, Workability, Properties of Stone Dust Concrete. INTRODUCTION Ever since, the introduction of Ordinary Portland Cement [OPC] there is a continuous demand for concrete, whose price has also gone up considerably due to raise in the cost of its constituent raw materials over the years. Rapid industrialization due to the implementation of successive Five Year Plans have contributed to the accumulation of industrial wastes and by-products which pose disposal and environmental problems and causing health hazards. On the other hand, the social commitment of providing Shelter for All is becoming a distant even for those with an assured decent income, leaving along other segments of people in lower economic level. 108

2 To overcome the above problems, studies have been initiated in the use of non-conventional materials for partial replacement of cement by fly ash in concrete; Conversion of agricultural wastes like saw-dust, cork granules, rice-husk, coconut pith into some useful building materials, etc. Industrial by-products which were once disposed-off as a waste material are finding ever increasing use in the construction industry. These industrial wastes have been mainly used for quite sometime as fillers in roads and embankments. But at present, they are used in the manufacture of cementitious materials and light weight aggregates etc. Besides the above advantages, savings in energy utilization of industrial wastes in the manufacture of cement and aggregates are of a very special significance in the Indian context of power deficit and starvation. Apart from the binder materials, alternate materials for the other constituents of concrete like, pebbles (well rounded aggregate) as coarse aggregate [CA] and crushed stone dust as fine aggregate [FA] are possible. However, studies on the latter are very limited and rare. At present CA is mostly obtained from hard broken granite stones and the by-product is Crusher Dust or Stone Dust. It is also referred to as Manufactured Sand. According to ASTM : C , it is the product obtained by crushing stone, gravel or air-colled iron blast furnace slag, specially processed to assure suitable particle shape as well as gradation. Although the specifications for sand (fine aggregate) to be used in mortar and concrete do permit the use of crushed stone dust, there appears to be a general hesitation amongst the field engineers, regarding its use, even in those areas where crushed stone dust is available almost free of cost in abundance. The general tendency is to use river sand only, even if it has to be brought from long distances. However, the potential use of manufactured sand as FA in concrete has not been fully exploited, in practice. Studies on the strength characteristics of concrete using stone dust as fine aggregate after removing the fines to confirm to IS gradation (passing 150 microns) have revealed the above characteristics are comparable with the conventional concrete. However the effect of the materials (less than 150 microns) on the strength of concrete and mortar need to be ascertained. If there is a possibility of using unprocessed stone dust in the above, there will be further saving in the effort involved in processing and there will be a complete solution to the disposal problems. LITERATURE REVIEW Sand mining is banned by various states in India, and with the increasing demand for river sand for construction works, the Civil Engineers, have expressed the need to promote use of manufactured sand in the construction industry. As per report, manufactured sand is widely used all around the world because of its consistent gradation and zero impurity 6. One of the earliest investigations on the suitability of manufacture sand for making quality concrete was carried out by Ghosh and other 1 at Central Road Research Institute [CRRI], New Delhi. They carried out the various tests on the physical properties of manufactured sand obtained from a few sources in U.P. to determine their suitability as a FA. Mortar making property, compression strength, flexural, abrasion loss, drying shrinkage and bond strength of concrete were determined for all the samples and concluded that manufactured sand can be confidently used as FA to produce quality concrete. However, split tensile strength tests and durability studies were not conducted to determine the relative performance of manufactured sand concrete. Malhotra and Canette 2 studies the performance of concrete, incorporating limestone dust (obtained from limestone quarries after crushing operations) as a partial replacement for natural sand in concrete. Three series of concrete mixes with w/c ratio 0.70, 0.53 and 0.40 respectively, incorporating lime stone dust from 5-20% were prepared by direct replacement on an equivalent mass of recombined sand basis. The properties of fresh concrete i.e. slump, unit weight and air 109

3 content (%) were determined. Compressive strength, freezing and thawing, drying and shrinkage, creep were determined for hardened concrete. They have concluded that incorporation of upto 10% limestone dust as a partial replacement for FA in concrete with w/c = 0.70 and 5% limestone dust in concrete with w/c = 0.53 does not significantly affect the properties of fresh and hardened concrete. However, there is considerable loss in slump, irrespective of w/c ratios, if lime stone dust is in excess of 10%. Nagaraj and Lahida Banu 3 used manufactured sand and pebbles as FA and CA in concrete and used the method of re-proportioning concrete to obtain M65 concrete and has concluded that the above combination of CA and FA can be used with confidence in concrete. Misra 4 studied the water requirements and compressive strength of cement mortar using manufactured sand as FA, with FM ranging from 0.50 to 2.0 and 75% and 100% flow of mortar. Based on the above extensive experimental investigations, he had concluded that the strength of mortar with manufactured sand is higher than that of the corresponding mix with cement (sand) mortar. He has recommended the use of manufactured sand for mortar and has cautioned the removal of excessive proportions of very fine particles. Studies were carried out at Pondicherry Engineering Collage, Puduchery 5 for using manufactured sand as FA in concrete and its compressive, flexural and split tensile strengths; sand abrasion; elastic modulus; mortar making properties and durability test under various acidic and alkaline mediums were determined and the performance compared with conventional concrete for M15 and M20 concretes. The size of manufacture sand used in the above study was restricted to 4.75 mm to 150 microns i.e. the size range presented in IS specification. From the studies, it is concluded that the manufactured sand can be used in the concrete effectively by replacing normal river sand. Sieve analysis of the raw samples revealed that the fine materials content (i.e. less than 150 microns) was at the maximum 10% and it was generally between 5-10%. Being the case it would be of interest to study the properties of concrete and mortar using the raw sample as such in the above. The suitability of Crushed Granite Fine (CGF) to replace river sand in concrete production for use in rigid pavement was investigated by Manasseh 7. Slump, compressive strength and indirect tensile strength tests were performed on fresh and hardened concrete. The 28 day peak compressive and indirect tensile strength values of N/mm 2 and 2.30 N/mm 2 respectively, were obtained with the partial replacement of river sand with 20 per cent CGF, as against values of N/mm 2 and 1.75 N/mm 2 obtained with the use of river sand as fine aggregate. Based on economic analysis and results of tests, river sand replaced with 20 per cent CGF is recommended for use in the production of concrete for use in rigid pavement. Conservation of river sand in addition to better ways of disposing wastes from the quarry sites are some of the merits of using CGF. The investigation carried out by Nagabhushana and Sharada Bai 8 studied the properties of mortar and concrete in which Crushed Rock Powder (CRP) was used as a partial and full replacement for natural sand. For mortar, CRP is replaced at percentages of 20, 40, 60, 80 and 100. The strength properties of concrete were investigated by replacing natural sand by CRP at replacement level of 20, 30, and 40 per cents. Aggrarwal et al. 9 have carried out experimental investigations to study the effect of use of bottom ash as a replacement of fine aggregate. Different strength properties were studied and it consisted of compressive strength, flexural strength and splitting tensile strength. The strength development for various percentages of 0-50 replacement of fine aggregates with bottom ash can easily be equated to the strength development of normal concrete at various ages. Siddique 10 presented the results of an experimental investigation carried out to evaluate the mechanical properties of concrete mixtures in which fine aggregate i.e., sand was partially replaced with Class F fly ash. Sand was replaced in five percentages. i.e., 10, 20, 30, 40 and 50 of class F fly ash by weight. Tests were performed for the evaluation of properties of fresh concrete. Compressive strength, splitting tensile strength, flexural strength and modulus of elasticity were determined at 7, 110

4 14, 28, 56, 91 and 365 days. Test results indicated significant improvement in the strength properties of plain concrete by the inclusion of fly ash as partial replacement of fine aggregate (sand), and could be effectively used in Structural Concrete. Kondraivendhan et al. 11 explored the possibility of making concrete using pond ash as partial replacement of river sand in producing M20 and M40 grade concrete. The pond ash replacement levels were 10, 20, 30, 40 and 50 per cent. The compressive strength of different grades of concrete was evaluated at 7, 28, 56 and 90 days by testing cubical specimens. The results were compared with the control concrete. Nataraja et al. 12 investigated the possibility of utilizing Granulated Blast Furnace Slag (GBFS) as a sand substitute in cement mortar, in order to reduce environment problems related to aggregate mining and waste disposal. In this investigation, cement mortar mix 1:3 and GBFS at 0, 25, 50, 75 and 100 per cent replacement to natural sand for constant w/c ratio of 0.5 was considered. The work was extended to 100 per cent replacements of natural sand with GBFS for w/c ratios of 0.4 and 0.6. The flow characteristics of the various mixes and their compressive strengths at various ages were studied. From this study, it was observed that GBFS could be utilized partially as alternative construction material for natural sand in mortar applications. Reduction in workability expressed as flow could be compensated by adding suitable percentage of super plasticizer. Thandavamoorthy 13 studies the feasibility of local soil instead of river sand in making concrete as fine aggregate in producing M25 grade concrete. A nominal mix of 1:1:2 and M25 grade was adopted. The soil cube yielded a compressive strength of 28 N/mm 2 while sand cube yielded N/mm 2. The split tensile strength of soil concrete was N/mm 2. For conventional concrete, the same value was N/mm 2. The modulus of rupture values were 8.1 N/mm 2 for soil concrete and 6.96 N/mm 2 for sand concrete. It was concluded that the properties of local soil was as good as the regular river sand and it can be used as fine aggregate in the production of concrete. EXPERIMENTAL INVESTIGATIONS The crusher plants located in and around Puducherry are the sources for crushed stone dust (manufactured sand). The stone dust of granite origin collected from Thiruvakkarai crusher plant, Vanur, Tamil Nadu was taken for this investigation. At present the dust is used as a filler material in making bituminous top for roads and the rate of production of dust is about 20-25% of total quantity. Only small amounts of these wastes have been used in road making and in the manufactured of building materials such as, light weight aggregate bricks and autoclaved blocks. Laboratory investigations are carried out on the stone dust obtained form the crusher plant and the results are compared with the existing IS Standards to decide on their suitability as FA in concrete. It was proposed to use of unprocessed stone dust in making of concrete as a substitute for river sand. First gradation of the stone dust and river and were determined by conducting size analyzing as per IS The result of sieve analysis and various physical property are given in table 1 and 2 for stone dust and river sand. The design mix M15 and M20 were adopted according to IS The Workability tests, compressive strength, split tensile strength, flexural strength, modulus of elasticity and abrasion resistance test of concrete made of stone dust and river sand were determined by appropriate testing. 111

5 SI. No Sieve Size (mm) Table 1: Sieve Analysis of Stone dust (Raw Sample) and River Sand Weight retained (gm) Stone Dust River Sand (Reference) Cumulative Cumulative Weight Cumula- Cumula- Cumula-tive % Passing Retained tive tive % Passing %Weight (gm) weight %weight Retained retained retained Cumulative Weight Retained (gm) (gm) < SI. No Water absorption on SSD basis (%) Table 2: Physical test of Stone dust and river sand Bulk sp. Gravity Unit wt. on SSD basis (Kg/m) (gm/cc) 112 Maximum Bulkage Remarks % Reference % Stone dust RESULTS AND DISCUSSION The specific gravity of river sand was where as for stone dust it was The fineness modulus for river sand was whereas for stone dust it was (sieves ranging from 4.75mm 150 microns). From the above it was found that both the given river sand and stone dust having similar properties. The result of the various workability tests are given in table 3 and 4 for stone dust concrete and conventional concrete for w/c ratios, ranging between W/C Table 3: Workability tests on Stone Dust Slump (mm) Flow Table (%) V-B Time (secs.) Compaction factor M15 M20 M15 M20 M15 M20 M15 M W/C Table 4: Workability tests on Reference Concrete Slump (mm) Flow Table (%) V-B Time (secs.) Compaction Factor M15 M20 M15 M20 M15 M20 M15 M

6 Slump is observed only for w/c exceeding 0.60 for M15 grade and for w/c exceeding 0.65 for M20 grade whereas for conventional concrete slump values are observed for w/c 0.55 onwards. Slump value at the high w/c ratio (0.65) is only one-third and about one -sixth for M15 and M20 grades concrete when compared to conventional concrete. Result of compaction factor, flow table and V-B time tests of constant stone dust concretes of M15 & M20 grades, are consistent with the results of conventional concretes of the same grades with regard to the trend in the results. Cube compressive strength of reference and stone dust concretes for M15 and M20 are given in Table 6. From the above result it can be seen that the compressive strength at 28 days of stone dust gives the higher compressive strength, which is 35% and 4% higher then the reference concrete strength for M15 and M20 grade concrete respectively. SI. No Table 5: Compressive Strength Test of Different Concretes Average Compressive Strength (N/mm 2 ) Mix Proportion W/C 7 days 14 days 28 days 56 days M15 1 Reference :1.87: Stone dust :1.84: M20 3 Reference :1.53: Stone dust :1.51: The result of cylinder strength, Split tensile and flexural strength of stone dust concretes are given in Table 7 has the same trend as that of the cube compressive strength for all grades of concrete. Further, the ratio of cylinder to cube compressive strength bears a constant ratio irrespective of the grades and the ratio is within the limits prescribed for conventional concretes. The split tensile strength of stone dust is higher than reference concrete by 15.50% and 2.20% for M15 and M20 grades, whereas the flexural strength is higher by 35.09% and 18.26% for the corresponding grades. Comparing the cube compressive strength, split tensile strength and flexural strength, it is seen that the increase in flexural strength over the reference concrete is the highest. This is due to the greater angularity of stone dust which offers a layer bonding surface between the cement paste and fine aggregate. SI. No Table 6: Cylindrical Compressive Strength, Tensile and Flexural Strength Test Average Average split Description Cylindrical tensile strength Compressive (N/mm 2 ) strength (N/mm 2 ) Average flexural strength (N/mm 2 ) M15 M20 M15 M20 M15 M20 1 Reference Stone dust The result of Ec and Abrasion resistance test for various concretes are given in the Table 8. From the results, it is found that the Ec for stone dust concrete is slightly less (5 to 15%) than that of the reference concrete. The abrasion loss of stone dust concretes are less than that of reference concrete ( 5 to 20%). 113

7 Table 7: Modulus of Elasticity and Abrasion resistance test SI. No Description Elastic Modulus (N/mm 2 ) Abrasion Resistance test (% Loss) M15 M20 M15 M20 1 Reference 2.29 x x Stone dust 1.94 x x CONCLUSIONS Following conclusions are arrived at based on the experimental investigations carried out in this study: 1. In general, workability of stone dust concretes are less than that of conventional concrete for identical grades and water cement ratios. 2. Stone dust obtained form various sources in and around Puducherry satisfies the requirement as specified in IS standards. 3. Stone dust concrete (using the raw sample) has equal or slightly higher strength than reference concrete for M15 and M20 grades considered in this study. 4. There is no difference in the quantity of materials required between both the types of concrete. Inspite of this, there will be a tremendous advantage from environmental and ecological considerations (in the long run) due to the use of stone dust concrete, irrespective of the use of stone dust in the raw form or processed from i.e. removing the fines which pass through 150 microns to bring the sample within the gradation limits specified in IS code. However it should ensured that too much of fine materials are not present. An upper limit of 20% (for materials 150 microns) seems to be desirable to attribute the desired strength and durability. REFERENCES 1. Ghosh, R.K., Sethi, K.L., Prakash, Suitability of manufactured sand for making quality concrete, Road Research Paper No.111, Central Road Research Institute (CRRI), New Delhi 1970, pp Malhotra, V.M., Carette, G.G., Performance of concrete incorporating lime stone dust as partial replacement for sand, ACI Journal, May-June 1985, pp Nagaraj, T.S., Lahida Banu., Efficient utilization of rockdust and pebbles as aggregates in portland cement concrete, The India Concrete Journal, January 1996, pp Misra R.N., Use of stone dust from crushers in cement-sand mortars, The Indian Concrete Journal, August 1984, pp Uma Maheswari, G., Strength and durability studies on manufactured sand concrete M. Tech. Thesis, Submitted to the Pondicherry University, December 1996, pp Elavenil, S., and Vijaya, B., (2013), Manufactured sand, a solution and an alternative to river sand and in concrete manufacturing, Journal of Engineering, Computers and Applied Sciences (JEC&AS) Volume 2, No.2, February, pp Manasseh, S., (2010), Use of Crushed Granite Fine as Replacement to River Sand in Concrete Production, JOEL,Civil Engineering Department University of Agriculture P.M.B. 2373, Makurdi, Benue State, Nigeria. 8. Nagabhushana, K. And Sharada Bai, H., (2011), Use of Crushed Rock Powder as Replacement of Fine Aggregate in Mortar and Concrete, JSS Academy of Technical Education, Bangalore, India. 114

8 9. Aggarwal, P., Aggarwal, Y., and Gupta, S.M., (2007), Effect of bottom ash as replacement of fine aggregates in concrete, National Institute of Technology, Kurukshetra, India. 10. Siddique, R., (2002) Effect of fine aggregate replacement with Class-F fly ash on the mechanical properties of concrete, Institute of Engineering and Technology, Deemed University, Patiala, India. 11. Kondraivendhan, B., Sairam, V., and Nandagopal, K., (2011). Influence of pond ash as fine aggregate on strength and durability of concrete, The Indian Concrete Journal, 85(10), pp Nataraja, M.C., Dileep Kumar, P.G., Manu, A.S., and Sanjay, M.C., (2013) Use of granulated blast furnace slag as fine aggregate in cement mortar, International Journal of Structural & Civil Engg. Research, Vol.2 No. 2, May, pp Thandavamoorthy. T.S., (2014), Feasibility of making concrete from soil mstead of River sand, Indian concrete Institue Journal Value 15 April June 2014.pp I.S. : Specification for ordinary and low heat portland cement, BIS, New Delhi. 15. I.S. : Specification for coarse and fine aggregate from natural sources for concrete, BIS New Delhi. 16. I.S. : , Methods of test for strength of concrete, BIS, New Delhi. 17. I.S. : 2386 (Part I) 1963, Methods of test for aggregates for concrete, part I: Particle size and shape, BIS, New Delhi. 18. I.S. : 2386 (Part III) 1963, Methods of test for aggregates for concrete, Part III: Specific gravity, density, voids, absorption and bulking, BIS New Delhi. 19. I.S. : 2386 (Part V) 1963, Methods of test for aggregates for concrete, Part V: Soundness, BIS, New Delhi. 20. S.P. : , Hand book on Concrete mixes, BIS, New Delhi. 21. Er.S.Thirougnaname and Dr.T.Sundararajan, Studies on Rice Husk Ash Cement Mortar, International Journal of Advanced Research in Engineering & Technology (IJARET), Volume 4, Issue 7, 2013, pp , ISSN Print: , ISSN Online: 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 , ISSN Print: , ISSN Online: Er.S.Thirougnaname and Dr.T.Sundararajan, Studies on Rice Husk Ash Cement Concrete, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 6, 2013, pp , ISSN Print: , ISSN Online: AUTHOR S DETAIL Er. S. Thirougnaname, M.Tech., MIE., MISTE., FIAH., MIWWA., AMISE., MIT Arb., MICI., Project Engineer, Pondicherry Tourism Development Corporation, Puducherry, India. 115