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Development of Self Compacting Concrete using Different Range of Cement Content Prashant Bhuva, Anant Patel, Elizabeth George, Darshana Bhatt PG Students, Dept. of Structure Engg., Associate Professors. , Dept. of Structure Engg., Gujarat Technological University BVM Engineering College Gujarat, India. Gujarat, India. 1 [email protected] [email protected] [email protected] [email protected] AbstractFor the development of Self Compacting Concrete no Specific Method of Mix Design is Available. In this paper an attempt is made to develop SCC of Different Strength by Using various ranges of cements and Fly Ash, with appropriate quantity of Super plasticizer and VMA. KeywordsCompaction, Compressive Strength, Fly Ash, Super Plasticizer, Viscosity Modifying Agent, Water/Paste Ratio. I. INTRODUCTION Concrete has been recorded in existence as long ago a 7000BC. It was used by the ancient Egyptians and the Romans used it to build the Coliseums and Hadrian’s Wall. Throughout history, concrete has proven itself to be a most flexible and durable construction material, used to resist Compression. Today, modern technology has led to high performance concrete with super-tensile load qualities. Also, by the substitution of Portland cement with fly ash or ground granulated blast-furnace slag (GGBS) in the mix, the resulting concrete is stronger, the secret lies in making a dense concrete through proper compaction. It has been found through various research and practical observations that in-situ concreting is highly affected by insufficient and improper compaction especially while concreting in congested reinforced areas. Also compaction requires better quality of shuttering, scaffolding, stages etc. in order to resist the additional forces derived due to devices used for compaction. Self compacting concrete (SCC) is a concrete which does not require compaction with the use of Super Plasticizers and Viscosity Modifying Agents (VMA) leading to well compacted concrete without much external efforts and the strength and durability of concrete does not suffer. This makes the SCC sustainable as it saves the energy. Development of self-compacting concrete (SCC) is a desirable achievement in the construction industry in order to overcome problems associated with cast-in-place concrete. Self compacting concrete is not affected by the skills of workers, the shape and amount of reinforcing bars or the arrangement of a structure and, due to its high-fluidity and resistance to segregation it can be pumped longer distances. The concept of self-compacting concrete was proposed in 1986 by Professor Hajime Okamura, but the prototype was first developed in 1988 in Japan, at the University of Tokyo, as in [8]. Previous mechanism for achieving self-compact ability: Achieving self-compact ability involves not only high deformability of paste or mortar. When the concrete flows through the confined zone of reinforcing bars. The following methods to achieve self- compact ability (Fig.1), as in [8] Fig.1 Mechanism for achieving self-compact ability Limited aggregate content Low water-powder ratio Use of super plasticizer The SCC nature shows the basic concept. The method for achieving self-compact ability involves not only high deformability of paste or mortar, as shown in (Fig. 1). But, also resistance to segregation between coarse aggregate and mortar when the concrete flows through the confined zone of reinforcing bar. Homogeneity of SCC is its ability to remain un-segregated during transport and placing, as shown in Fig.2. National Conference on Recent Trends in Engineering & Technology 13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India

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Page 1: Development of Self Compacting Concrete using Different ... · Development of Self Compacting Concrete using Different Range of Cement Content Prashant Bhuva, Anant Patel, Elizabeth

Development of Self Compacting Concrete using Different Range of Cement Content

Prashant Bhuva, Anant Patel, Elizabeth George, Darshana Bhatt

PG Students, Dept. of Structure Engg., Associate Professors. , Dept. of Structure Engg.,

Gujarat Technological University BVM Engineering College

Gujarat, India. Gujarat, India. [email protected] [email protected][email protected] [email protected]

Abstract—For the development of Self Compacting Concrete no Specific Method of Mix Design is Available. In this paper anattempt is made to develop SCC of Different Strength by Using various ranges of cements and Fly Ash, with appropriate quantity of Super plasticizer and VMA.

Keywords— Compaction, Compressive Strength, Fly Ash, Super Plasticizer, Viscosity Modifying Agent, Water/Paste Ratio.

I. INTRODUCTION

Concrete has been recorded in existence as long ago a 7000BC. It was used by the ancient Egyptians and the Romans used it to build the Coliseums and Hadrian’s Wall. Throughout history, concrete has proven itself to be a most flexible and durable construction material, used to resist Compression. Today, modern technology has led to high performance concrete with super-tensile load qualities. Also, by the substitution of Portland cement with fly ash or ground granulated blast-furnace slag (GGBS) in the mix, the resulting concrete is stronger, the secret lies in making a dense concrete through proper compaction.

It has been found through various research and practical observations that in-situ concreting is highly affected by insufficient and improper compaction especially while concreting in congested reinforced areas. Also compaction requires better quality of shuttering, scaffolding, stages etc. in order to resist the additional forces derived due to devices used for compaction. Self compacting concrete (SCC) is a concrete which does not require compaction with the use of Super Plasticizers and Viscosity Modifying Agents (VMA) leading to well compacted concrete without much external efforts and the strength and durability of concrete does not suffer. This makes the SCC sustainable as it saves the energy.

Development of self-compacting concrete (SCC) is a desirable achievement in the construction industry in order to overcome problems associated with cast-in-place concrete. Self compacting concrete is not affected by the skills of workers, the shape and amount of reinforcing bars or the arrangement of a structure and, due to its high-fluidity and resistance to segregation it can be pumped longer distances. The concept of self-compacting concrete was proposed in 1986 by Professor Hajime Okamura, but the prototype was

first developed in 1988 in Japan, at the University of Tokyo, as in [8].

Previous mechanism for achieving self-compact ability:Achieving self-compact ability involves not only high

deformability of paste or mortar. When the concrete flowsthrough the confined zone of reinforcing bars. The followingmethods to achieve self- compact ability (Fig.1), as in [8]

Fig.1 Mechanism for achieving self-compact ability

Limited aggregate content Low water-powder ratio Use of super plasticizer

The SCC nature shows the basic concept. The method for achieving self-compact ability involves not only high deformability of paste or mortar, as shown in (Fig. 1). But,also resistance to segregation between coarse aggregate and mortar when the concrete flows through the confined zone of reinforcing bar. Homogeneity of SCC is its ability to remain un-segregated during transport and placing, as shown in Fig.2.

National Conference on Recent Trends in Engineering & Technology

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India

Page 2: Development of Self Compacting Concrete using Different ... · Development of Self Compacting Concrete using Different Range of Cement Content Prashant Bhuva, Anant Patel, Elizabeth

Fig.2 Mechanism for Mortar

II. MATERIALS AND METHODS

A. Materials used in developing SCC are having following properties: Cement: Ordinary Portland cement of 53 grades

(ultra tech.) available in local market is used in the investigation.

Coarse and Fine Aggregate: Locally available Crushed stone with 16mm maximum size. Natural sand with 4.75 mm maximum size is used as fine aggregate.

Fly Ash: Fly ash is one of the most extensively used by-product materials in the construction field resembling portland cement. Class F Fly ash obtained from “Wanakbori Thermal Power Station, kheda, India.

Super plasticizer: A polycarboxylic ether based super plasticizer is used, which is of brown colour having relative density 1.08+0.01 and pH value as 7+1. The ingredients values are shown in Table I.

TABLE I INGREDIENTS VALUE

Sr.

No.Ingredients Value

1 SP. Gravity for C.A 2.92

2 SP. Gravity for F.A 2.6

3 SP. Gravity for Fly Ash 2.3

4 SP. Gravity for Cement 3.15

6 Entrapped Air 2%

7 Voids 0.98

The first stage of the process is to fix the W/P ratio by performing ‘Relative Slump Cone Test’, and then optimizing the dosage of Super-Plasticizer by ‘Marsh Cone Test’ keeping fixed percentage of VMA (0.31%).

B. Determination of Optimum Super-Plasticizer Dosage in Mortar

Marsh Cone Test:The apparatus used is a hollow inverted cone with an

aperture of 8 mm, as shown in Fig. 3.The procedure consists of introducing 1 litre of paste into

the cone and measuring the time taken for the flow out the bottom aperture. The flow time (T) is considering being a measure of the inverse of the fluidity; the measurements made are plotted on the curve, as shown in Fig. 4.

(a) (b)

Fig. 3 Marsh Cone

The graph plotted is used to define the saturation point of the super plasticizer, which is taken as the optimum dose of total cementious material. The saturation point is the dosage beyond which the fluidity dose not increases significantly.

Fig. 4 Test Results for Marsh Cone

National Conference on Recent Trends in Engineering & Technology

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India

Page 3: Development of Self Compacting Concrete using Different ... · Development of Self Compacting Concrete using Different Range of Cement Content Prashant Bhuva, Anant Patel, Elizabeth

C. Tests Conducted for Fresh Properties of Self Compacting Concrete

There are three key fresh properties of SCC for mix design purposes in the lab and for compliance purposes on site.

Filling ability, Passing ability and Resistance to segregation

Based on the EFNARC Guidelines, slump flow, visual stability, L-box, U-box, V-funnel, J-ring, filling box and column segregation tests are some of the available testing methods used to evaluate fresh properties.

III. MIX-DESIGN METHOD

Aim of this research is to develop SCC using cements of range 350 kg/m3 to 450 kg/m3 with various quantity of fly ash Varies from 150 kg/m3 to 250 kg/m3 by partially replacing fine and coarse aggregate .following step to achieve the SCC.

Quantity of cement and amount of fly ash to be added and fixed.

Fixing the water paste ratio to achieve by performing relative slump cone test on mortar.

After fixing W/P ratio and super plasticizer with given cement content and fly ash, aggregate quantities are found out and mix is done to verify the fresh properties of SCC

Cube are cast and cheeked for its strength by performing destructive and non destructive tests.

Table no. II and III shows the detail of same

TABLE II TRIAL MIXES

TABLE III SCC FRESH PROPERTIES

C.ATrial mixes

W/P Cement Fly Ash10mm 20mm

F.A Water S.P % VMA%

A1 1.2 300 150 447.93 298.62 912.46 192.53 1.77 1.33

A2 1.2 300 150 503.64 335.76 909.35 192.53 1.77 1.33

A3 1.1 300 150 461.31 307.54 803.18 224 1.77 1.33

A4 1.1 300 150 461.31 307.54 803.18 224 1.77 -

A5 1.1 300 150 461.31 307.54 803.18 224 1.55 -

C1 1.0 350 250 747.18 - 809.45 219.80 0.8 0.31

C2 1.1 350 200 778.76 - 843.65 217.87 0.8 0.31

C3 1.2 350 150 816.10 - 884.11 211.59 0.8 0.31

E1 1.0 450 250 690.13 690.13 251.55 0.8 0.31

E2 1.1 450 200 718.60 - 718.60 252.79 0.8 0.31

E3 1.2 450 150 753.11 753.11 249.68 0.8 0.31

Slump V-Funnel L-Box

Acceptance criteriaT50 (2-5 sec)Dia (650-800)

Acceptance criteriaTo & T5(8-12 sec)

Acceptance criteriah2/h1(0.8-1.0)

Trial mixes

T50inSec.

Diamm

Remarks

T0insec

T5inSec

Remarks

h2/h1TimeinSec.

Remarks

A1 - 410 N.A - - N.A - - N.A

A2 - - N.A - - N.A - - N.A

A3 - 610 N.A - - N.A - - N.A

A4 5.0 710 Good - - N.A - - N.A

A5 9.0 630 N.A - - N.A - - N.A

C1 4.3 710 Good 5.5 7 Good 0.9 5.5 Good

C2 2.71 700 Good 4.1 5 Good 0.85 6.0 Good

C3 20 430 N.A - - N.A - - N.A

E1 1.66 740 Good 3.58 4.50 Good 1.0 2.56 Good

E2 2.3 650 Good 4.48 4.92 Good 0.9 2.43 Good

E3 1.17 700 Good 3.42 3.68 Good 1.0 1.7 Good

National Conference on Recent Trends in Engineering & Technology

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India

Page 4: Development of Self Compacting Concrete using Different ... · Development of Self Compacting Concrete using Different Range of Cement Content Prashant Bhuva, Anant Patel, Elizabeth

A. Non Destructive Test for Self Compacting Concrete

1) Rebound Hammer Test:The Rebound hammer test measures the elastic rebound

of concrete and is primarily used for estimation of concrete strength and for comparative investigations.

Fig. 5 Rebound Hammer

The rebound values R of the sample cubes were measured using the concrete test hammer. The compressive strength was then determined with the pressure testing machine. Limitations: Although, rebound hammer provides a quickinexpensive means of checking uniformity of concrete, it has serious limitations and these must be recognised. The results are effected by: Smoothness of surface under test Size, shape and rigidity of the specimen Age of specimen Surface and internal moisture conditions of the

concrete Type of coarse aggregate.

2) Ultrasonic Pulse Velocity Test The ultrasonic instrument is used for the non-

destructive test of concrete. In particular, the following properties can be determined: Uniformity of concrete Cavity, cracks detection Concrete strength.

Fig. 6 Ultrasonic Pulse Velocity Test Equipment

TABLE IV TEST RESULTS FOR REBOUND HAMMER AND ULTRA-SONIC PLUSE VELOCITY TEST EQUIPMENT

Sr.N0.

Trial Mix

Rebound No. (R) 7-Days

Compressive Strength 7-Days

in MPa

Velocity m/sec

1 C1 25 17.3 6233

2 C2 22 13.0 6180

3 C3 22.5 13.5 6076

4 E1 25.5 17.9 6013

5 E2 24.2 16.1 3596

6 E3 24.7 16.8 3563

Fig. 7 Comparative Test Results

IV. CONCLUSION

Taking into account of findings from this study, the following conclusions can be drawn: From the marsh cone test conducted for different

dosage of SP, it is observed that the optimum dosage of SP is 0.8% of Cementious material is the saturated point, and with further increase in the percentage of SP, their is no effect in the flowability is noted.

Further it is conclude from rebound hammer test that,trial mixes C1and E1 having higher Cementious material give higher compressive strength.

Ultrasonic pulse velocity test gives acceptable limits of Velocity having good conditions as per IS:13311-Part I ‘Velocity Criterion for Concrete Quality Grading’.

ACKNOWLEDGMENT

We sincerely thank our advisors Prof. Elizabeth George and Dr. Darshana R Bhatt (B.V.M Engg. College V.V.Nagar), for their guidance, suggestions, and continuous support throughout our research work. Our greatly thanks to Principal Dr. F.S.Umrigar Sir and Dr.A.K Verma H.O.D of Structure Dept. We also thankful for the sincere support given by the Engineering Experts at Ambuja Knowledge centre-Baroda. We greatly appreciate all the support that they had been given to us.

National Conference on Recent Trends in Engineering & Technology

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India

Page 5: Development of Self Compacting Concrete using Different ... · Development of Self Compacting Concrete using Different Range of Cement Content Prashant Bhuva, Anant Patel, Elizabeth

REFERENCES

[1] Ambuja Technical literature series 98, of Self Compacting Concrete at Ambuja knowledge City Baroda, 2006.

[2] Anant Patel, “Hardend Properties of Self Compacting Concrete”, Second National Conference on Emerging Vistas of Technology in 21st Century, pp. 37-44. 4-Dec (2010).

[3] Burak Felekoglu, Selc-ukTurkel, Bulent Baradan. “Effect of water/cement ratio on the fresh and hardened properties of self-compacting concrete”, Department of Civil Engineering magazine of Dokuz Eylul University, 35160 Izmir, Turkey, 23 January 2006.

[4] Erdogan Ozbay, Ahmet Oztas, Adil Baykasoglu, Hakan Ozbebek ” “Investigating mix proportions of high strength self compacting concrete by using Taguchi method”. Construction and Building Materials, p.694–702, 23 May 2009.

[5] Khayat K.H., Ghezal A.,” Utility of Statistical models in Proportioning Self-Compacting Concrete”, Proceedings, RILEM International symposium on Self-Compacting Concrete, Stockholm, p. 345-359.1999.

[6] M. R. Taylor, F. D. Lydon and B. I. G. Barr” Mix proportions for high strength concrete”, Cardiff School of Engineering, Division of Civil Engineering, University of Wales, Cardiff CF2 of, Vol.15,25 April 1996.

[7] Nagamoto N., Ozawa K., “Mixture properties of Self-Compacting, High-Performance Concrete, Proceedings”, Third CANMET/ACI International Conferences on Design and Materials and Recent Advances in Concrete Technology, SP-172, V. M. Malhotra, American Concrete Institute, Farmington Hills, , p. 623-637, March. 1997.

[8] Okamura H., Ozawa K., “Mix Design for Self-Compacting Concrete”, Concrete Library of Japanese Society of Civil Engineers, p. 107-120, June 25, 1995.

[9] Paratibha AGGARWAL, Rafat SIDDIQUE, Yogesh AGGARWAL, Surinder M GUPTA,” Self-CompactingConcrete - Procedure for Mix Design”, Leonardo Electronic Journal of Practices and Technologies ISSN 1583-1078Issue.p. 15-24, 12, January-June 2008.

[10] Patel, R., Hossain, K.M.A., Shehata, M., Bouzoubaa, N., and Lachemi, M., “Development of statistical models for mixture design of high-volume fly ash self consolidating concrete”, ACI Materials Journal, Vol. 101, No. 4, , pp. 294-302. July-August 2000.

[11] Pierre-Claude Aitcin,“Developments the application high-performance concretes “, University of Sherbrooke, Sherbrooke, Quebec, Construction and Building Materials, Vol. 9, No. 1, pp. 13-17, 1995.

[12] P.L. Domone,” Self-compacting concrete: An analysis of 11 years of case studies”, Cement & Concrete Composites 28 (2006).

[13] Prashant Bhuva, “Evaluation of Properties of Fresh Self Compacting Concrete”, Second National Conference on Emerging Vistas of Technology in 21st Century, pp. 27-36. 4-Dec (2010).

[14] Ratchayut Kasemchaisiri and Somnuk Tangtermsirikul, “Properties of Self-Compacting Concrete in Corpora ting Bottom Ash as a Partial Replacement of Fine Aggregate”. Concrete And material magazine, 21 Nov 2007.

[15] R. Sri Ravindrarajah, D. Siladyi and B. Adamopoulos“Development Of High-Strength Self-Compacting Concrete With Reduced Segregation Potential” 3rd International RILEM Symposium , Reykjavik, Iceland, Centre for Built Infrastructure Research, University of Technology, Sydney, Australia, , 17-20 August 2003.

[16] R. Sri Ravindrarajah, F. Farrokhzadi and A. Lahoud “Properties Of Flowing Concrete And Self-Compacting Concrete With High-Performance Superplasticizer ,Centre for Built Infrastructure Research, University of Technology, Sydney, Australia, vol. 24,p.550-565.April 2003.

[17] S.K. AgarwalU, Irshad Masood, S.K. Malhotra.” Compatibility of super plasticizers with different cements”, Central Building Research Institute, Construction and Building Materials’.p 253-259, 14 June 2000.

[18] Steen Rostam,” High performance concrete cover-why it is needed, and how to achieve it in practice” Consfrucfion und Building Materials, Vol. 10, No. 5, pp. 407-421, 1996.

[19] Surendra P. Shah & W. Jason Weiss , “High Performance Concrete: Strength, Permeability, And Shrinkage Cracking”. 6th International Congress, Global Construction, Ultimate Concrete Opportunities, Dundee, U.K. – 5-7 July 2005.

[20] Zhuguo Li “State of workability design technology for fresh concrete “,Cement and Concrete Research 37 1308–1320,2007.

National Conference on Recent Trends in Engineering & Technology

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India