DEVELOPMENT OF SLAG BASED LOWER STRENGTH SELF COMPACTING CONCRETE

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 2, February 218, pp , Article ID: IJCIET_9_2_7 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed DEVELOPMENT OF SLAG BASED LOWER STRENGTH SELF COMPACTING CONCRETE AND EXPERIMENTAL ASSESSMENT ON ITS STRENGTH AND ELASTIC PROPERTIES V. Manjula Research Scholar, Civil Engineering Department, M.G.R. Educational and Research Institute University, Maduravoyal, India Dr. T. Felixkala H.O.D. Civil Engineering Department, M.G.R. Educational and Research Institute University, Maduravoyal, India ABSTRACT The main scope of this research paper is to achieve the optimum level of GGBS to develop the lower final strength and cost effective Self Compacting Concrete (SCC). An extensive experimental study of mechanical properties and the elastic behaviour of slag based self compacting concrete is presented in this paper. To maintain the fresh concrete s rheological properties and, at the same time, achieve lower final strength, reduced amount of Portland cement needs to be proposed in the mixture design. In this current research, SCC was produced by blending GGBS with cement in three different ratios and 5% Crusher Rejected Fines is incorporated in all scc mixes as useful disposal of a waste product from quarry end and also which leads to economical benefits. Based on the experimental results, it was found that SCC mixture containing 5% GGBS replacement to cement and 5% CRF to river sand exhibited possibility of lower target strength of M25grade. The obtained experimental E value is applied to explore the possibility of structural application of the developed SCC mixes. Key words: GGBS, Crusher Rejected Fines, Compressive strength, Split Tensile Strength Flexural Sstrength and Youngs Modulus Cite this Article: V. Manjula and Dr. T. Felixkala, Development of Slag Based Lower Strength Self Compacting Concrete and Experimental Assessment on its Strength and Elastic Properties. International Journal of Civil Engineering and Technology, 9(2), 218, pp INTRODUCTION Adoption of SCC offers substantial benefits in enhancing construction productivity, reducing overall cost and improving work environment. The higher powder content, limited volume 56 editor@iaeme.com

2 Development of Slag Based Lower Strength Self Compacting Concrete and Experimental Assessment on its Strength and Elastic Properties and nominal size of coarse aggregate, large quantity of super plasticisers represent design requirements in achieving the self compatibility. (EFNARC guidelines 22). It is also known that some mineral admixtures may improve rheological properties and reduce thermallyinduced cracking of concrete due to the reduction in the overall heat of hydration, and increase the workability and long-term properties of concrete. (Dhruvkumar H. Patel et al). In order to maintain the deformability along with flow ability of SCC a chemical admixture is an indispensible ingredient. The use of ground granulated blast-furnace slag with cement improves the microstructure, final strength, and durability of hardened concrete. For a newly development material like lower strength self compacting concrete requires studies on strength and elastic property are of paramount important for instilling confidence amongst engineers and builders. Seshaphani et al., (213). The replaeble rate up to 3% is desirable for the SCC production without adversely affecting the strength and durability properties. (G.Ganesh Prabhu et al, 215). 2. MATERIALS Ordinary Portland Cement was used in this study as a binding material. According to IS 2386 part1:1963, sieve analysis was carried out to determine grain size distribution for Natural River Sand, Coarse Aggregate of maximum size 12.5mm, and crusher rejected fines. The results were compared in the fig no.1. The crusher rejected fines was obtained from the local crusher at kunrathur, Chennai. Super plasticizer as a high range water reducer without retarding was used in producing SCC. Table 1 The physical properties of the materials MATERIAL PROPERTIES Maximum size : 12.5mm Specific gravity : 2.72 Crushed granite stone Bulk density : 15 Fineness modulus : 5.49 Water absorption :.5% Specific gravity : 2.6 Density : kg/m3 River sand Fineness modulus : 3.84 Water absorption : 1.32% Grading Zone : zone III Specific gravity : 2.55 Bulk density : Crusher rejected fines Fineness modulus : 3.9 Water absorption : 2.31% Grading Zone : zone III Cement Specific gravity : 3.15 Fineness :4% Specific gravity : 2.58 Ground granulated blast furnace slag Fineness : 8% Water P H value : 7 Super plasticizer Master Glenium sky BASF B editor@iaeme.com

3 PASSING %GE V. Manjula and Dr. T. Felixkala Graduation of River Sand and Crusher Rejected Fines by seive analysis test, fig no mm 4.75mm 2.36 mm 1.18 mm 6^m 3^m 15^m pan SEIVE SIZE RIVER SAND CRF 2.1. Mix proportion and test methods for evaluating the fresh properties of SCC In the present research the mix design was based on Okamura and Ozawa method, which is a simple and rational method. In this method, the coarse aggregate and fine aggregate contents are fixed and self-compatibility is to be achieved by adjusting the water / powder ratio and super plasticizer dosage. T Hajime Okamura et al. (23), established the rational mix-design methods proportioning coarse aggregate and mortar as 5% and 4% respectively of the total aggregate volume.the required water/powder ratio and admixture ratio is determined by conducting a number of trial batches until we reach the SCC properties such as resistant to segregation and excessive bleeding were reached. The flowability properties of different trial mixes of scc obtained were ascertained using slump flow test, v- funnel test and L box test four mixex thatb satisfies all these criteria were adopted for further study. The details of the selected mix proportions and their fresh properties are given in the table no.2.and 3. Table 2 Mix proportions SI.No. Materials SCC 1 SCC 2 SCC 3 SCC 4 1. Cement Kg/m GGBS Kg/m River sand Kg/m CRF Kg/m Coarse aggregate Kg/m Water litres Super plastizer 1%.5%.5%.55% Table 3 Fresh Properties of scc mixes Slump Test V Funnel Test L Box Test Slump mm T5 T5 Time for Discharge Time Sec. min. Sec. H2/H1 SCC1 Nominal Mix GGBS - 3% SCC GGBS - 5% SCC GGBS - 7% SCC editor@iaeme.com

4 Development of Slag Based Lower Strength Self Compacting Concrete and Experimental Assessment on its Strength and Elastic Properties 3. RESULTS AND DISCUSSIONS 3.1. Compressive Strength The compressive strength of concrete represents one of the most important features used in the design rules of the concrete structures. The compressive strength developments of cubes at 7 th, 28 th, 9th, and 18 days of the different mixes were shown in table no. is the average values of three specimens. The compressive strength test was carried out as per ASTM C39. From the test results, it is observed that the SCC mixes blended with GGBS is clearly pointing to the possibility of lower target strength M2-M3 grade. However the mix SCC3, 5% ggbs to cement and 5%CRF to river sand reached its target strength M25 at 28 days. And there is reduction in compressive strength at 7% replacement in early and in later days SCC4 mix also reaches the target strength M25. The reduction in strength is mainly due to reduction in cement content. The control concrete SCC1 had shown slightly higher strengths at all ages. Table 4 Compressive strength at different ages Compressive strength N/mm 2 7 th day 28 th day 9 th day 18 th day SCC 1 control Mix SCC 2 GGBS - 3% SCC 3 GGBS - 5% SCC 4 GGBS - 7% Split Tensile Strength and Flexural Strength The average split tensile strength and flexural strength for the SCC mix specimens at 7 th day and at 28 th day are summarised in table no. The SCC mix containing 3% of GGBS to cement and 5%CRF to river sand as replacement materials gives the ultimate value of split tensile strength and flexural strength. From the test results, it is observed that the Tensile Strength and Flexural strength of all specimens continued to increase with age.the rheological properties of GGBS reduces the development of cracks and that in returns helps in the development of split tensile strength and flexural strength compared to control mix. Table 5 Tensile Strength and Flexural strength at different ages MIX DESIGNATION SPLIT TENSILE STRENGTH FLEXURAL STRENGTH N/mm 2 N/mm 2 7 TH DAY 28 TH DAY 7 TH DAY 28 TH DAY SCC 1 control Mix SCC 2 GGBS - 3% SCC 3 GGBS - 5% SCC 4 GGBS - 7% editor@iaeme.com

5 FLEXURAL STRENGTH MPA SPLIT TENSILE STRNGTH MPa COMPRSSIVE STRENGTH N/mm2 V. Manjula and Dr. T. Felixkala COMPARISON OF COMPRESSIVE SRENGTH OF ALL SCC MIXTURES AT DIFFERENT AGES % 2% 4% 6% 8% GGBS SUBSTITUTION RATE 7th day 28th day 9th day 18th day COMPARASION OF SPLIT TENSILE STRENGTH OF SCC MIXES AT DIFFERENT AGES fig 3 % % 3% 5% 3% 5% 7%, %, 1.7 % 2% 4% 6% 8% GGBS SUBSTITUTION PERCENTAGE 7th day 28th day Comparision of flexural strength of scc mixes at different ages 6 5 % 4 3% 5% % 7%, % 3 5% 7%, % 2% 4% 6% 8% GGBS SUBSTITUTION PERCENTAGE 7th day 28th day 3.3. Elastic Modulus One of the most significant mechanical parameters of concrete is the elastic modulus, which indicates the concrete ability to deform elastically.the static elasticity values f all SCC specimens were summarised in table no 6. The control mix had the highest elastic modulus when compared to other slag based SCC mixes. 6 editor@iaeme.com

6 STRESS Mpa Development of Slag Based Lower Strength Self Compacting Concrete and Experimental Assessment on its Strength and Elastic Properties SCC 1 control Mix SCC 2 GGBS - 3% & SCC 3 GGBS - 5% & SCC 4 GGBS - 7% & Table 6 E values at different ages Modulus of elasticity N/mm 2 28 th day 9 th day COMPARISON OF STRESS - STRAIN CURVE FOR 28TH DAY STRAIN control mix 3% ggbs& 5% Crf 7% ggbs & 5% crf 5% ggbs& 5% crf 5 STRESS - STRAIN CURVE FOR 9 DAYS STRESS N/mm STRAIN (% ggbs, % crf) 3% ggbs 5% crf 5% ggbs 5% crf 7% ggbs 5% crf 4. CONCLUSIONS The developed slag based SCC mixes were highly segregation resistance and had good flowability and passing ability.. The addition of GGBS in concrete reduces the water demand and improves workability. Based on the experimental results, it was found that SCC mixture containing 5% GGBS replacement to cement and 5% CRF to river sand exhibited possibility of target strength of M25 SCC grade, compared to other SCC mixes. The youngs modulus of GGBS blended SCC mixes satisfies the conventinal code method. The obtained experimental E value is applied to explore the possibility of structural application of the 61 editor@iaeme.com

7 V. Manjula and Dr. T. Felixkala developed SCC mixes. The results are clearly pointing to the possibility of lower-strength self-compacting concretes production and thus makes it possible to expand the usability portfolio of this type of modern construction materialsswith regard to its lower production costs. REFERENCES [1] Dhruvkumar H. Patel et al., (May-214) LITERATURE REVIEW ON SELF COMPACTING CONCRETE, International Journal For Technological Research In Engineering, Vol 1, Issue 9. [2] Mallesh.M., Sharanbasava, Reena.K., Madhukaran Experimental Studies On M25 Grade Of Self Compacting Concrete. [3] Selvi.K., T. Mahendran, N. Attikumaran (216) Experimental Investigation On Modulus of Elasticity of Self-Compacting Concrete Journal of Applied Physics and Engineering, Vol-1, N.2.. [4] N. Anand, G. Prince Arulraj Experimental Investigation on Mechanical Properties Of Self Compacting Concrete Under Elevated Temperatures. [5] Pamnani Nanak.Jet al., (213) Comparison Between Mechanical Properties Of M3 Grade Self Compacting Concrete For Conventional Water Immersion and Few Non-Water Based Curing Techniques International Journal of Engineering and Advanced Technology,vol -3,no. 2.. [6] G.Ganesh Prabhu et al, (215), Mechanical and Durability Properties Of Concrete Made with Used Foundry Sand as Fine Aggregrat Advances in Materials Science and Engineering, [7] Seshaphani et al., (213) Evaluation of relationship between mechanical properties of high strength self compacting concrete American journal of engineering research,vol 2, no.4. [8] R.Thenmozhi and N. Balasubramani.,(215) Experimental Study on Self Compacting Concrete (M25) with 25% Fly ash Incorporating 1% Replacement of Coconut-Shell as Coarse Aggregate, Vol. 14,No.2, pp [9] EFNARC - (European Federation of national trade associations representing producers and applicators of specialist building products), Specifications and guidelines for self compacting concrete [1] M.S. Vijaykumar and Dr. R. Saravanan. Analysis of Epoxy Nano Clay Composites Compressive Strength during Salt Spray Test. International Journal of Mechanical Engineering and Technology, 8(5), 217, pp [11] R. Gopa K umar and Dr R. Rajesh. A Study on the Abrasion resistance, Compressive strength and Hardness of Banana Fibre Reinforced Natural Rubber Composites. International Journal of Advanced Research in Engi neering and Technology, 7 (3), 216, pp [12] M.S. Vijaykumar and Dr. R. Saravanan. Analysis of Epoxy Nano Clay Composites Compressive Strength during Tropical Exposure Test. International Journal of Mechanical Engineering and Technology, 8(5), 217, pp editor@iaeme.com