EXPERIMENTAL STUDY ON STRENGTH AND WORKABILITY OF CONCRETE USING

ULTRAFINE SLAG ALCCOFINE

Abstract - The purpose of this research to study the compressive strength and workability of cement based concrete by partial replacement of cement with ultrafine materials for improving the durability of concrete to sustain a longer life span and producing a greener and quality concrete. Incorporating ultrafine slag as a mineral admixture improve the workability and pump ability of fresh concrete. These ultrafine slag act as the filler in concrete thus reducing its permeability. In this paper, the mechanical strength development of high strength concrete with ultrafine slag (Alccofine) is carried on different grades of concrete are used and partial replacement of cement with Alccofine has studied.”

Keywords: Alccofine, workability, compressive strength.

INTRODUCTION

Creating quality concrete in the present climate does not depend solely on achieving a high strength property but improving the durability of concrete to sustain a longer life span and producing a greener concrete are becoming one of the main criteria in obtaining quality concrete Slag is the byproduct formed when molten iron blast furnace slag is rapidly cooled by immersing it in water. These slags are finely grounded and mixed with ordinary Portland cement(OPC) to produce binding properties. Due to its fineness it also increases the workability of concrete for a same water -cement ratio.” In today's modern era especially in developing countries like India use of High strength concrete (above M50) have gained pace. In particular, construction of high rise buildings and long span brides, high strength concretes are used. Also due to availability of high strength steel bars Fe500, Fe550 use of high strength concrete has become necessity. Silica fume is the byproduct of silica industry. Its generation is only 2%. In India its very expensive and for making high strength and durable concrete silica fume is recommended till date. But ultra-fine slag can be a good substitute for silica fume as its particle size is same as that that of silica fume and it is easily available. In India ultra-fine slag is manufactured by Ambuja cement in support of Holcim cement. In India Ambuja cement is the only manufacturer of ultra-fine slag. Its brand name is Alccofine. Per bag weights 25kg. Alccofine is manufactured in two grades i.e. 1203 and 1201.Grade 1103 is for self-compacting concrete and 1201 is used for high strength concrete.

In “this work the effect of ultra-fine slag on the properties of concrete is studied. For the current experimental study M50 grade concrete mix is used as per IS :10262-1982.Alccofine” “replacement resulted in higher early strength, lower permeability and better quality control as compared to” OPC.”

EXPERIMENTAL PROGRAMThe aim of this experimental program is to compare the behaviour of Alccofine 1203 in use as a supplementary cementing material when subjected to different test.

MATERIALS USEDCEMENT

Grade 43 OPC JP cement was used for experimental purposes while casting of beams, cylinders, cubes for all concrete mixes. Various basic tests have been summarised as follows:

2.1.2 “Fine Aggregates

The sand was first sieved through 4.75mm sieve to remove any particles larger than 4.75mm and then was washed to remove the dust.

Properties of fine aggregates used have been presented in fallowing table. “The aggregates were sieved through a set of sieve analysis presented in table 3. The aggregate was found to belong to zone 4.”

1 2Ragini Kaushal Sana Zafar

1&2“Department of Civil Engineering, Madan Mohan Malviya University of Technology Gorakhpur,

Table1: Properties of cement

Table2: Physical properties of fine aggregate”

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RESULT AND DISCUSSION“In this paper, compressive strength and flexural strength of various concrete mixes incorporating ultrafine slag (Alccofine-1203) in varying percentages is discussed.”

4.1Ultrafine slag

the effect of ultrafine slag upon concrete has been presented as fallows upon compressive strength and flexural strength.

4.2Compressive strength

The specimen was tested at different ages i.e. 7days, 14days and 28 days for compressive strength. The load is applied at a constant rate thus ensuring progressive increase in stress as failure approached

“Total weight taken = 1000gmFineness modulus of sand = 2.56

2.1.3 Coarse aggregateCoarse aggregate can be defined as any material retained on IS no. 4.75. the “crushed stone is generally used as a coarse aggregate. The size of work decides the maximum size of coarse aggregate. 10mm aggregate was used for this work which was locally available.

F.M of coarse aggregate=6.83

3.Mix design

“For HPC there is no specific method of design mix. In the present investigation approximation from I.S methods as per I.S.10262:2009 and also as per the available literature on ultrafine slag are used. In order to achieve high strength lower w/c ratio is adopted and to achieve high strength lower w/c ratio is adopted and to achieve good workability Alccofine 1203 is used. In the present investigation w/c ratio used is 0.29”

Experimental Study on Strength and Workability of Concrete Using Ultrafine Slag Alccofine

Table2: Physical properties of fine aggregate”

Table4: Physical properties of coarse” aggregates(10mm)

Table5: Sieve analysis of coarse aggregate

Table 6: Ratio of mix design

Table7: Compressive strength of concrete mixes, incorporating varying percentage of Alccofine 1203 at 7,14 and 28 days

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Vision & Quest, Vol. 7, No. 1, Jan-June 2017ISSN: 0975-8410

4.4Flexural testing of beams reinforced with steel fibres“The results of flexural testing are presented in table. The test was carried out conforming to Is 516-1959 to obtain flexural strength of concrete beams at the age of 7, 14 and 28 days under two-point loading technique. The beams were tested using universal testing machine (U.T.M) as per I.S 516-1959

4.3 Flexural strength“In order to study the effect on flexural strength, the beams containing different proportion of alccofine-1203 were prepared and kept for curing for 7,14 and 28 days. The test was conducted on U.T.M as per I.S 516-1959”

Table8: Nomenclature for beams

T a b l e 8 : N o m e n c l a t u r e f o r b e a m s

Table9: “Flexural strength of plain concrete beams, incorporating varying percentages of Alccofine1203 at 7,14 and 28 days”

Table10: “Flexural strength of reinforced concrete beams, incorporating varying percentage of Alccofine 1203 at 7,14 and 28 days”

Table11: Flexural strength of concrete beams incorporating 12% alccofine-12003 and varying percentage of steel fibres at 7, 14 and 28 days

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Experimental Study on Strength and Workability of Concrete Using Ultrafine Slag Alccofine

[9] IS: 4031-1988 Methods for Physical Tests for Hydraulic Cement. Bureau of Indian Standards, New Delhi, India.

[10] IS: 8112-1989 Standard Code of Practice for 43-Grade Ordinary Portland cement. Bureau of Indian Standards, New Delhi, India.

[11] Iliana Rodriguez Viacava, Antonio Aguado dea Cea, Gemma Rodriguez de Sensale, “Self Compacting Concrete of medium concrete characteristics Strength.” Construction and Building Materials 30(2012) p.p. 776-782.

[12] Nan, Su; Kung –Chung, H; His – Wen, C; “A simple mix design method for self-compacting concrete.” Cement and Concrete Research 31(2001) p.p. 1799-1807

CONCLUSION

Although the subject of this study seems as strength and durability of Alccofine 1203 in general, as the title implies but this was rather a study on concrete in particular. A new method of generating HPC has been investigated by using ultrafine slag Alccofine1203. Following are observations made by this research.

5.1Compressive Strength“The test results indicated that, when 8% to 12% by weight replacement of Alccofine 1203 for cement is done, compressive strength increases. When 14% replacement of cement is done strength starts decreasing. Compressive strength of ultrafine slag concrete at 28 days compared to control mix was increased by 11% to 29 % on increasing the silica fume content from 8% to 14%.” Also there is 10% to 27% increase in 28 days' strength with 14 % replacement when compared to control specimen. decrease of compressive strength is noticed when compared to 12% replacement level. The results here establish that the optimum value for replacement of cement by Alccofine 1203 is 12%.

5.2Flexural StrengthFrom the results listed in Tables 09 and 10, it is obtained that in both cases of plain and reinforced concrete beams the “28 days strength of all the mixes is invariably higher than corresponding 7 days and 14 days strength. This is due to continuous hydration of cement with concrete and improved particle packing owing to the dimensions of Alccofine particles.” However, a fall in strength was seen when replacement level exceeded 12 %.

REFERENCES:

[1] A.M Neville, Properties of concrete, 4th edition (1995), Addition Wesley Lapman Ltd England. Page 269-317,359-405

[2] M.S. Pawar, A.C.Saoji, “performance of self-compacting concrete using alccofine”, International journal of engineering Research and application, Aug 2013.

[3] M.S.Shetty, Concrete technology-theory and practice, S Chand publication (2005).

[4] IS: 456-2000 Code of practice for plain and reinforced concrete (third edition). Bureau of Indian standards, New Delhi, India.

[5] IS: 516-1959 Methods of tests for strength of Concrete.BIS, New Delhi, India.

[6] IS: 1199-1959 Methods of sampling and analysis of Concrete.BIS, New Delhi, India.

[7] IS 383:1970 Specification for coarse and fine aggregates from natural sources for concrete (second revision) Jan 2007.

[8] IS 2386(Part 1):1963 Methods of test for aggregates for concrete: Part 1 Particle size and shape Jan 2007.

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