INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING Volume 2, No 3, 2012

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1 INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING Volume 2, No 3, 2012 Copyright 2010 All right reerved Integrated Publihing ervice Reearch article ISSN Invetigation on fly ah concrete for pavement Vanita Aggarwal 1, Gupta S.M 2, Sachdeva S.N 3 1- Aociate Profeor, CED, MM Engineering College, Mullana (Deemed Univerity) 2- Profeor, Civil Engineering department, NIT, Kurukhetra 3- Profeor, Civil Engineering department, NIT, Kurukhetra aggarwal_vanita@rediffmail.com doi:10.088/ijcer ABSTRACT The work reported through thi paper i an experimental work conducted on High Performance concrete (HPC) with uper platicizer with the aim to report it uitability for concrete pavement. In thi tudy, the effect of varying proportion of fly ah (30% and 40%) on compreive trength of high performance concrete ha been evaluated. The mix deign tudied were- M30, M40 and M50 to compare the effect of fly ah addition on the propertie of thee concrete mixe. In all nine concrete mixe have been deigned, three a conventional concrete for three grade under dicuion and ix a HPC with fly ah with varying percentage of fly ah. The concrete mix deigning ha been done in accordance with Indian tandard recommended guideline i.e. IS: 1022:1982. All the concrete mixe have been tudied in term of compreive trength and flexural trength at, and. All the material ued have been kept ame throughout the tudy to get a perfect comparion of value of reult. Keyword: High performance concrete, Fly ah, Concrete mixe, Compreive trength, Flexural trength, Concrete pavement. 1. Introduction In the era of growth and development in all field, contruction indutry can not afford to be an exception. Infact, concrete indutry ha undergone challenging advance ince time immortal. High performance concrete (HPC) in that erie i quite young and i jut 20 year old. High performance concrete i generally confued with high trength concrete. However, HPC i one which eentially poee three characteritic namely high workability, high trength and high durability (Mehta and Gjorv, 1982). The miconception that high trength concrete will necearily be highly durable ha led to cracking and premature failure of many concrete tructure (Mehta and Burrow, 2001). Though field data available tell about the ucce tory of high performance concrete in many tructure, the preent tudy wa aimed at analyzing the uitability of HPC with fly ah for concrete pavement. The whole world i producing a big reerve of fly ah through it thermal power plant but the fraction of fly ah being ued for contructional purpoe i not ignificant. The ituation i even carier in India. Currently, only 40 million ton of fly ah i being ued in a variety of engineering work againt a generation of 125 million tone of fly ah annually in India (Rao and Kumar, 199). The ue of fly ah in high percentage a a replacement to cement will addre two global problem i.e. one, the problem of dipoal of bulky volume of fly ah in landfill and econd, the CO 2 emiion in atmophere cauing global warming from cement indutry (American Coal Ah Aociation, 1995). In hort, we can ay that the concrete indutry, due to it large ize, i the ideal home for economic and afe incorporation of million tone of indutrial by-product uch a fly ah. Therefore cement replacement in concrete by fly ah Received on December, 2011 Publihed on February

2 Invetigation on Fly ah Concrete for Pavement will be highly advantageou from the tandpoint of cot, economy, and durability, ecological and environmental benefit. The preent invetigation include the tudy of compreive and flexural trength of HVFC with two different proportion of fly ah content. Long term Compreive trength ( at age > ) and flexural trength of fly ah concrete ha been found more a compared to concrete without fly ah. Moreover the rate of gain of flexural trength of fly ah concrete i more when compared to the ame of compreive trength. 2. Reearch ignificance The topic choen for reearch i of importance epecially in Indian cenario, a very mall length of concrete pavement, here, i incorporating ue of fly ah in it. The reaon i either ignorance about the uitability of fly ah in HPC for concrete pavement or i lack of confidence in the tet reult available, a mot of the reearch in the aid area ha been carried out abroad. Moreover, there i no conitency in the propertie of fly ah available from different ource. So, the tet reult of one place can not be utilized a uch for other place. The aim of the preent reearch i to evaluate the performance of HPC with varying percentage of fly ah for concrete pavement. Compreive and flexural trength are the mot important propertie that affect the performance of concrete pavement (Kumar, Tike and Nanda, 200). Hence, thee propertie have been invetigated in the preent tudy for variou concrete mixe with different percentage of fly ah. The objective of uing fly ah a an admixture to concrete i to reduce heat of hydration, reduce cement content reulting in better economy, improved durability & workability and to afeguard environment from hazard of CO 2 emiion from cement indutry and landfill of fly ah dipoal. All fly ah mixture exhibited ubtantially higher rate of trength gain a compared with non- fly ah control mixe (Mullick, 200). 2.1 Experimental tet detail For achieving the objective of the preent reearch, an experimental program wa planned to invetigate the effect of varying percentage of fly ah i.e. 30% and 40% by weight of cement, on compreive and flexural trength of concrete. The invetigation for compreive and flexural trength on concrete with and without fly ah at different age were conducted. The ingredient for HVFA concrete are cement, fly ah, fine aggregate, coare aggregate and water. Laboratory tet were conducted on cement, fine aggregate, coare aggregate, wherea tet reult of fly ah were performed through a profeional laboratory. The effect of replacing cement with fly ah in varying percentage (0%, 30% and 40%) on compreive trength of high volume fly ah concrete at moit curing wa to be carried out by cube teting at the age of, and. However, the beam pecimen were cat, cured and teted for flexural trength by two point loading ytem at, and of age. The tet reult were ued for etimating the repective trength at the age of one year. 3. Experimental tet etup The pecimen were teted on ton capacity motorized UTM. Specimen were taken out from the curing tank at repective age of teting and teted immediately on removal from the water, while they were till in the wet condition. The poition of the cube when teted wa at right angle of that a cat. The axi of the pecimen wa carefully aligned with the centre 8

3 Mix deignation Water (liter) Cement (Kg) Fly ah (% of cementitiou content) Coare Aggregate (Kg) Invetigation on Fly ah Concrete for Pavement of thrut of the pherically eated plate. The load wa applied gradually and without hock and increaed continuouly at the rate of approximately 14N/mm 2 / minute till the failure of the pecimen and thu the compreive trength wa found out (Shetty, 2002). The flexural trength tet wa conducted on beam of tandard ize of 50cmX10cmX10cm by two point loading ytem (Neville and Brook, 2009). The load wa increaed at the rate of 35 N/mm 2 / minute till the failure of beam pecimen. 3.1 Material ued Cement Ordinary Portland cement of 43 grade conforming to IS 8112 (1989) wa ued. The cement wa teted in accordance with the method of tet pecified in IS: 8112 (1989) Fine Aggregate For preparation of concrete mix 4.5 mm (maximum) fine aggregate were ued Coare Aggregate 40:0 proportion of 10 mm and 20mm ize coare aggregate were adopted Fly ah Fly ah wa having bulk denity 1000 kg/mm 3 and pecific gravity Potable water Potable tap water wa ued for the preparation of all concrete pecimen Chemical ued Super platicizer baed on poly carboxylic technology wa ued for high trength concrete. 3.2 Concrete mix proportion Cement i replaced by an equal weight of fly ah by 30% and 40% and the mix deign were done in accordance with IS:1022:1982. Table 1: Mix Proportion for Different Specimen for M30 grade concrete (w/c=0.42) Compreive Flexural Fine Aggregat e (Kg) T

4 Mix deignation Water (liter) Cement (Kg) Fly ah (Kg) Fine Aggregate (Kg) Coare Aggregate (Kg) Invetigation on Fly ah Concrete for Pavement T % T % Mix deignation for M30 1. T 1--Reference Mix for M T 2--30% cement replaced by fly ah for M T 3--40% cement replaced by fly ah for M30. Table 2: Mix Proportion for Different Specimen for M40 grade concrete (w/c= 0.35) Compreive Flexural T T % T % Mix deignation for M40 1. T 4--Reference Mix for M T 5--30% cement replaced by fly ah for M T --40% cement replaced by fly ah for M40. 89

5 Mix deignation Water (liter) Cement (Kg) Fly ah (Kg) Fine Aggregate (Kg) Coare Aggregate (Kg) Invetigation on Fly ah Concrete for Pavement Table 3: Mix Proportion for Different Specimen for M50 grade concrete (w/c= 0.35) Compreive Flexural T T % T % Mix deignation for M50 1. T --Reference Mix for M T 8--30% cement replaced by fly ah for M T 9--40% cement replaced by fly ah for M Reult and dicuion Total number of 81cube were cat, cured and teted for compreive trength 11 of variou concrete mixe (IS: 45: 2000). Alo 5 beam were cat, cured and teted for variou concrete mixe for their repective flexural trength (ASTM C8 / C8M - 10). The following apect were tudied 1. The effect on compreive trength of concrete at age, and uing fly ah in varying percentage a a partial replacement of cement for three grade of high trength concrete. 2. The effect on flexural trength of concrete at age and uing fly ah in varying percentage a a partial replacement of cement for three grade of high trength concrete. 3. Projected compreive trength at age of for variou mix deign i compared with that of actual value at. 880

6 Invetigation on Fly ah Concrete for Pavement The following graph indicate the tet reult for compreive trength at and for M30, M40 and M50 grade of concrete. The tet reult of Flexural trength at have alo been repreented in form of a graph below. Figure 1: Comparion of percentage of Flyah with variou trength of concrete It i clear from the value and graph that the compreive trength at for fly ah concrete i le than that at. The compreive trength decreae with increae in fly ah content. The compreive trength at for fly ah concrete i alo le than that for concrete without fly ah for all replacement level. The reference mix achieve a compreive trength of 40.5 MPa at while the fly ah concrete with cement replacement of 30% and 40% attain trength of 3.9 MPa and 34.8 MPa repectively for M30 grade of concrete. Thu, the fly ah concrete with 30% and 40% replacement of the cement, gain 93.15% and 85.54% repectively in trength w.r.t. the trength of reference mix at the age of for M-30 grade of concrete. A imilar tet reult pattern i oberved for M40 and M50 grade of concrete. 881

7 Invetigation on Fly ah Concrete for Pavement The lower compreive trength at the initial age can be due to the reaon of reduction of the quantity of cement by the replacement with fly ah, reulting in weakening the coheion of the cement pate and adheion to the aggregate particle. A tated in literature, approximately 5% trength rendering primary mineralogical phae 13 i developed at the ultimate hydration of OPC. The balance Ca(OH) 2 hardly contribute for trength a the fly ah replaced for cement do not contribute for chemical reaction, becaue of the reaon that ufficient cementitiou action of fly ah i not activated at the initial tage and thu the non reactive quantity of fly ah, at thi tage, reflect inignificant effect on compreive trength. At the later age, improvement in the trength i oberved due to the reaon that the urplu lime releaed from OPC hydration become the ource for pozzolanic reaction, contributing for additional mineralogy a econdary hydrated mineralogy 13, majority contributing for additional trength. Thu, the non reactive portion of fly ah fill up the matrix to render packing effect i.e. phyical effect of improving the microtructure of the hydrated cement pate. 5. Concluion On the bai of the reult and dicuion of thi invetigation following concluion can be inferred: 1. In all the concrete mixe, the compreive trength decreae with the increae in replacement level of fly ah for cement in comparion to reference mixe at all the age. 2. The rate of development of compreive trength of fly ah concrete i more during the period from to than the correponding value for the initial period up to. 3. The rate of development of flexural trength i more a compared to that for compreive trength of fly ah concrete mixe. 4. The projected compreive trength of concrete with fly ah i quite comparable to targeted trength at. 5. High volume fly ah concrete mixe for all grade of concrete are much more economical than reference mixe.. Reference 1. Mehta, P.K. and Gjorv O. E., (1982), Propertie of Portland Cement Concrete containing Fly ah and Condened Silica Fume, Cement and Concrete Reearch Journal, Vol. 12, No. 5, pp Mehta,P.K.,and R.W.Burrow, (2001), Building Durable Structure in the 21 t Century, Concrete International 23(3), pp Rao, B.K. and Kumar Vimal, (199), Fly ah in high trength Concrete, Recent Advance in Civil Engineering, National Seminar, September, pp American Coal Ah Aociation, (1995), Fly Ah Fact for Highway Engineer, Federal Highway Adminitration, Report No. FHWA-SA , Wahington, DC, December. 882

8 Invetigation on Fly ah Concrete for Pavement 5. Kumar B., Tike G.K. and Nanda P.K., (200), Evaluation of propertie of high volume fly ah concrete for pavement, Journal of Material in Civil Engineering, Vol.19, No. 10, pp Mullick, A.K., (200), High Performance Concrete for Bridge and Highway Pavement, Proceeding of National Conference on Advance in Bridge Engineering, pp Shetty M.S., (2002), Concrete Technology- Theory and Practice, S.Chand & co. Ltd., New Delhi. 8. Neville A.M. and Brook J.J., (2009), Concrete Technology, 8 th edition, Pearon Education Ltd., Noida. 9. IS: 8112:1989, 43 Grade Ordinary Portland Cement Specification, Bureau of Indian Standard, New Delhi. 10. IS: 1022:1982, Recommended Guideline for Concrete Mix Deign Bureau of Indian Standard, New Delhi. 11. IS: 45:2000, Code of Practice for Plain and Reinforced Concrete, Bureau of Indian Standard, New Delhi. 12. ASTM C8 / C8M - 10 Standard Tet Method for Flexural of Concrete. 13. Bhanumathida N. and Kalida N., (2002), Prevention i better than cure Concrete i no exception, Mater Builder, 4(4), pp