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EFFECT OF W/C RATIO ON SELF COMPACTING CONCRETE OF M70 GRADE WITH FLY ASH AND MICRO SILICA AS FILLER MATERIAL. – PowerPoint PPT presentation

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Title: self compacting concrete


1
EFFECT OF W/C RATIO ON SELF COMPACTING CONCRETE
OF M70 GRADE WITH FLY ASH AND MICRO SILICA AS
FILLER MATERIAL
  • By
  • E. SRINIVASA RAO
  • Under the Guidance of
  • Smt. P. SRI LAKSHMI
  • Associate Professor
  • JNTUH College of Engineering
  • Hyderabad

2
INTRODUCTION
  • What is Self Compacting Concrete (SCC) ?
  • Defined as Concrete that is able to flow and
    consolidate under its own weight, completely fill
    the formwork even in the presence of dense
    reinforcement, whilst maintaining homogeneity and
    without the need for any additional compaction.
  • Why it is needed ?
  • Concrete is a versatile material extensively used
    in construction applications throughout the
    world.
  • Properly placed and cured concrete exhibits
    excellent compressive-force-resisting
    characteristics and engineers rely on it to
    perform in a myriad of situations.

3
  • However, if proper consolidation is not provided,
    its strength and durability could be
    questionable.
  • The growing use of concrete in special
    architectural configurations and closely spaced
    reinforcing bars have made it very important to
    produce concrete that ensures proper filling
    ability, good structural performance and adequate
    durability.
  • To help alleviate these concerns, Japanese
    researchers in the late 1980s developed a
    concrete mixture that deformed under its own
    weight, thus filling around and encapsulating
    reinforcing steel without any mechanical
    consolidation.

4
  • Self-Compacting Concrete offers new possibilities
    and prospects in the context of durability and
    strength of concrete.
  • As a result of the mix design, some properties of
    the hardened concrete can be different for SCC in
    comparison to normal vibrated concrete.
  • Mix design criterions are mostly focused on the
    type and mixture proportions of the constituents.
  • Adjustment of the water/cement ratio and
    superplasticizer dosage is one of the main key
    properties in proportioning of SCC mixtures.

5
  • Therefore, it is important to verify the
    mechanical properties of SCC before using it for
    practical applications, especially if the present
    design rules are applicable or if they need some
    modifications.
  • Recently, a great native interest had been
    derived towards self-compacting concrete.

6
  • Objective
  • The aim of the present dissertation is to study
    the effect of water-cement ratio (referred also
    as water-binder ratio) on workability and
    mechanical properties of self-compacting concrete
    of M70 grade with fly ash and micro silica as
    filler material.

7
  • Discussion Includes
  • Basic Concepts of SCC
  • Review of Literature
  • Test Methods on SCC
  • Experimental Investigations
  • Results and Discussions
  • Conclusions

8
Basic Concepts of SCC
  • Functional Requirement of SCC
  • Filling ability The ability of SCC to flow
    under its own weight into and fill completely all
    spaces within intricate formwork, containing
    obstacles, such as reinforcement.
  • Passing ability The ability of SCC to flow
    through openings approaching the size of the mix
    coarse aggregate, such as the spaces between
    steel reinforcing bars, without segregation.
  • Resistance to segregation The ability of SCC to
    remain homogeneous during transport, placing, and
    after placement.

9
  • Constituents of SCC
  • With regard to its composition, SCC consists of
    the same components as conventionally vibrated
    concrete, which are
  • Cement
  • Aggregates
  • Water
  • Chemical Admixtures i.e. Superplasticisers and
    Viscosity Modifying Agents
  • Mineral Admixtures i.e., Fly ash, Silica Fume,
    GGBFS etc.

10
  • Physical and Chemical Process of SCC
  • The physical process is due to the particles
    fineness of the supplementary cementing materials
    that are much smaller than that of the cement,
    thereby providing densely packed particles
    between fine aggregates and cement grains, and,
    hence, the reduction in porosity.
  • The chemical process is due to the activation of
    the non-crystalline silica, by the calcium
    hydroxide produced from the hydrating cement to
    form secondary calcium silicate hydrate that also
    fills the pore spaces and further reduces the
    porosity.

11
  • Advantages of SCC
  • Elimination of problems associated with
    vibration.
  • Ease of placement results in cost savings
    through reduced equipment and labour requirement.
  • Improves the quality, durability, and reliability
    of concrete structures due to better compaction
    and homogeneity of concrete.
  • Faster construction
  • Improves working conditions and productivity in
    construction industry.
  • Greater freedom in design.

12
  • Disadvantages of SCC
  • More stringent requirements on the selection of
    materials .
  • More precise measurement and monitoring of the
    constituent materials.
  • Requires more trial batches at laboratory as well
    as at ready-mixed concrete plants.
  • Costlier than conventional concrete based on
    concrete material cost (exception to placement
    cost).
  • Lack of globally accepted test standards and mix
    designs

13
REVIEW OF LITERATURE
  • Hajime Okamura et al. (2003) 4
  • In early 1980s, the problem of the durability of
    concrete structures was a major topic of interest
    in Japan.
  • The creation of durable concrete structures
    requires adequate compaction by skilled workers.
  • Lack of uniform and complete compaction as the
    primary factor responsible for poor performance
    of concrete structures.
  • Okamura solved the issue of degrading quality of
    concrete construction due to lack of compaction
    by the employment of SCC which is independent of
    the quality of construction work.

14
  • Introduced SCC in the late 1980s.
  • Early 1990s limited public knowledge about SCC,
    mainly in the Japanese language.
  • The prototype of SCC was completed in 1988 with
    available materials in the market and is shown
    below.

Self Compacting Concrete (Admixture Superplasticizer) Self Compacting Concrete (Admixture Superplasticizer) Self Compacting Concrete (Admixture Superplasticizer) Self Compacting Concrete (Admixture Superplasticizer) Self Compacting Concrete (Admixture Superplasticizer) Self Compacting Concrete (Admixture Superplasticizer) Self Compacting Concrete (Admixture Superplasticizer)
Air W Powder Powder S S G

Air W C S S G G
Conventional Concrete Conventional Concrete Conventional Concrete Conventional Concrete Conventional Concrete Conventional Concrete Conventional Concrete
15
Mechanism for achieving Self Compactability
(Okamura Ozawa)
16
  • Okamura and Ozawa proposed simple mix design
    method.
  • The coarse aggregate content in concrete is fixed
    at 50 of solid volume.
  • The fine aggregate content is fixed at 40 of
    mortar volume.
  • The water-powder ratio in volume is assumed as
    0.9 to 1.0, depending on the properties of the
    powder.
  • The SP dosage and the final w/b ratio are
    determined so as to ensure self compactability.
  • Nan Su et al. (2001) 14
  • Proposed new Mix design method based on
    experimental investigation carried out in Taiwan.
  • Packing Factor is used to determine the aggregate
    contents.
  • The volume of fine aggregate is more than coarse
    aggregate.

17
  • Simpler, easier for implementation and less-time
    consuming, requires smaller amount of binders and
    saves cost as compared to the method developed
    by JRMCA (Japanese Ready-Mixed Concrete
    Association).
  • Soo-Duck Hwang et al. (2006) 24
  • Studied the suitability of various test methods
    for workability assessment and proposed
    performance specifications.
  • 70 SCC mixes with w/c ranges of 0.35 and 0.42.
  • For structural applications slump flow ranges of
    620 to 720mm, L-box ratio (h2/h1)0.7, J-Ring
    flow of 600 to 700mm, V-Funnel Flow time 8 sec.

18
  • Paratibha Aggarwal et al. (2008) 20
  • Presented the experimental procedure to obtain
    the SCC mixes based on Japanese Method of mix
    design.
  • Initially trial mixes, CA 50 by volume of
    concrete, FA - 40 by volume of mortar with a w/c
    ratio of 0.90.
  • Later on by reducing the coarse aggregate from
    45 to 37 and increasing fine aggregate contents
    from 40 to 47.5 to attain the required results
    in all the tests i.e., slump flow, V-funnel and
    L-Box.
  • Dr. Hemant Sood et al. (2009) 2
  • Presented the experimental investigation of SCC
    using Flyash and Rice husk ash as mineral
    admixtures and testing rheological properties as
    per European Standards.

19
  • S. Venkateswara Rao et al. (2010) 25
  • Aims at developing standard and high strength SCC
    with different sizes of aggregate based on
    Nan-sus mix design procedure.
  • The variables involved in the study are size of
    aggregate, dosage of fly ash and grade of
    concrete.
  • SCC can be developed with all sizes of graded
    aggregate satisfying the SCC characteristics.
  • Noticed that the fresh properties improved with
    increase in fly ash percentages.
  • This study illustrated that the optimum dosages
    of fly ash were 52 addition in case of standard
    grade SCC and it is 31 addition in case of high
    strength Self Compacting Concrete.

20
  • C. Selvamony et al. (2010) 1
  • Studied the effectiveness of various percentages
    of mineral admixtures in producing SCC.
  • Okamura's method, based on EFNARC specifications,
    was adopted for mixed design.
  • In this study, the effect of replacing the
    cement, coarse aggregate and fine aggregate by
    limestone powder (LP) with silica fume (SF),
    quarry dust (QD) and clinkers respectively.
  • At the same constant SP dosage (08) and mineral
    additives content (30), LP showed the better
    workability.
  • More than 8 replacement of cement by lime stone
    powder with silica fume showed very significant
    reduction in the compressive strength.

21
  • N R Gaywala et al. (2011) 15
  • Studied the strength properties of SCC when
    cement is replaced by different proportions of
    fly ash ranging from 15 to 55 and are compared
    with M25 concrete.
  • The experimental result shows that the 15 fly
    ash mix gives the better strength characteristics
    as compared to the other fly ash mixes.
  • Prof. Shriram H. Mahure et al. (2013) 22
  • Aimed to develop Self Compacting Concrete using
    two industry wastes cement kiln dust (CKD) and
    fly ash (FA).
  • CKD was used to replace the cement content by
    three various percentages (5, 10 and 15) and fly
    ash was kept as constant (20).

22
  • The fresh properties of SCC follow direct
    relations with the CKD contents for all grades of
    concrete.
  • The compressive strength flexural strengths
    increases with increase in CKD contents up to
    10.
  • The mechanical properties of SCC follow direct
    relations with the CKD contents for all grades of
    concrete.

23
REVIEW OF LITERATURE Contd..
  • Summary
  • The literature review clearly indicates that the
    SCC having wider research scope and advantages in
    regard of performance, strength, quality and
    durability, etc.
  • Proper selection of materials, mix proportions
    based on various mix design methods, type of
    mineral and chemical admixtures, test methods and
    workability specifications are key concerns in
    the optimization and control testing of self
    compacting concrete.
  • In most of the test data evaluated that the
    design methods developed to predict the
    characteristics of SCC is based on different mix
    proportions, materials and on experimental work.

24
  • Therefore investigations are still to be required
    for making the self compacting concrete as a
    standard practice concrete from the economical
    and conventional applications point of view.
  • In this literature Nan Su mix design shows that
    it is a simpler, easier for implementation and
    less time consuming and cost effective method.
    This method is based on the investigation work
    carried out in Taiwan.
  • Hence in the present investigation work, Nan Su
    mix design was adopted for Indian conditions and
    examines the workability characteristics of SCC
    for different water binder ratios.

25
TEST METHODS ON SCC
  • Tests on Fresh Concrete
  • Slump-Flow Test
  • The slump-flow and T500 time is the easiest and
    most familiar test to evaluate the flowability
    and the flow rate of self-compacting concrete in
    the absence of obstructions. The diameter of the
    concrete circle is a measure of the filling
    ability of concrete.
  • The higher the slump flow value, the greater its
    ability to fill formwork under its own weight.

26
  • V-Funnel Test and V-Funnel at 5 minutes
  • This test is used to determine the filling
    ability (flowability) of the concrete. The funnel
    is filled with about 12 litres of concrete and
    the time taken for it to flow through the
    apparatus measured. After this the funnel can be
    refilled concrete and left for 5 minutes to
    settle.
  • This test measured the ease of flow of the
    concrete shorter flow times indicate greater
    flowability. After 5 minutes of setting,
    segregation of concrete will show a less
    continuous flow with an increase in flow time.

27
  • L-Box Test
  • This test is used to evaluate the fluidity of
    self-compacting concrete and its ability to pass
    through steel bars. The L-box consists of a
    chimney section and a channel section as
    described by Wu et al. With the L-box, the
    height of concrete in chimney, h1, the height of
    concrete in the channel section, h2, and the time
    for self-compacting concrete to reach 400 mm from
    three steel bars, T400, can be measured.
  • According to EFNARC , when the ratio of h2 to h1
    is larger than 0.8, self compacting concrete has
    good passing ability.

28
  • U-Box Test
  • This test is used to evaluate to the fluidity of
    self-compacting concrete and its ability to pass
    through steel bars. The U-box consists of a
    vessel that is divided by a middle wall in to two
    compartments. An opening with a sliding gate is
    fitted between the two sections. Reinforcing bars
    with nominal diameter of 13mm are installed at
    the gate with centre to centre spacing of 50mm.
    This creates a clear spacing of 35mm between the
    bars.

29
  • Tests on Hardened Concrete
  • Compressive Strength Test
  • Split Tensile Strength Test
  • Flexural Strength Test

30
EXPERIMENTAL INVESTIGATIONS
  • The present experimental investigations are
    focused to study the effect of water-cement
    ratios on fresh and hardened properties of self
    compacting concrete of M70 Grade.
  • The Concrete mixes contains different proportions
    of Fly Ash, Super plasticizers, water binder
    ratios and constant proportions of Cement, Micro
    Silica, VMA, Coarse aggregate and Fine aggregate.
  • A total of 5 concrete mixes with different
    combinations of water/cement ratios i.e., 0.23,
    0.24, 0.25, 0.26 and 0.27 were evaluated.

31
  • Materials Used
  • Cement
  • Ordinary Portland Cement 53 grade (OPC 53-Grade)
    was used throughout the experimental work.
  • Cement used has been tested for various
    proportions as per IS 4031-1988 and found to be
    confirming to various specifications of IS
    12269-1987.
  • The physical properties of the cement are shown
    in Table 1.

32
Table 1 Testing of Ordinary Portland Cement as per IS 4031 - 1988 Table 1 Testing of Ordinary Portland Cement as per IS 4031 - 1988 Table 1 Testing of Ordinary Portland Cement as per IS 4031 - 1988
Test Parameter Test Value IS 12269 1987 Recommendation
Specific Gravity 3.01 -----
Standard Consistency ( of cement by weight) 30.0 -----
Setting Time ( Minutes ) (1) Initial (2) Final 96 207 30 (Min.) 600 (Max.)
Compressive Strength ( MPa ) (1) 3 day (2) 7 day (3) 28 day 29.4 38.9 54.6 27 (Min.) 37 (Min.) 53 (Min.)
Soundness ( mm ) 2.0 10 (Max.)
33
  • Fine Aggregate
  • The sand used for the experimental program was
    locally available river sand.
  • The physical properties of the fine aggregate are
    shown in Table 2.
  • Coarse Aggregate
  • A locally available crushed stone aggregate of
    maximum nominal size 10 mm was used as coarse
    aggregate.
  • The physical properties of the coarse aggregate
    are shown in Table 3.

34
  • Water
  • Tap water free from deleterious materials is used
    for casting as well as curing of the specimens.
  • Fly Ash
  • Procured from ACC RMC Limited, Bachupally,
    Hyderabad, Andhra Pradesh, India.
  • Typical oxide composition of Indian fly ash is
    shown in Table 4.

35
  • Micro Silica
  • Obtained from Oriental Trexim Pvt. Ltd, Navi
    Mumbai, India.
  • The typical oxide composition details of micro
    silica are shown in Table 5.
  • Superplasticizer
  • GLENIUM B233 conforming to IS 9103-1999 and ASTM
    C494 Types F was used.
  • The details of the superplasticizer used are
    shown in Table 6.

36
  • Viscosity Modifying Agent (VMA)
  • The VMA used in this investigation was GLENIUM
    STREAM-2 which is a product of BASF construction
    chemicals.
  • The typical composition details of VMA are shown
    in Table 7.

37
  • MIX PROPORTIONING OF SCC
  • In the present investigations, Nan Su method of
    mix design was adopted to design the SCC mix.
  • The parameters that influence the mix proportions
    are packing factor, fine aggregate-total
    aggregate ratio and powder content.
  • The packing factor of aggregate is defined as the
    ratio of mass of aggregate of tightly packed
    state to that of loosely packed state.
  • The amount of fine aggregates will be more as
    compared to coarse aggregate from this method of
    mix which enhances the passing ability through
    gaps of reinforcement.

38
  • This method is simpler, easier for implementation
    and less time-consuming, requires a smaller
    amount of binders due to the increased sand
    content as compared to other mix design methods
    and hence saves cost.
  • The concrete mix was prepared for different
    water-binder ratios i.e., 0.23, 0.24, 0.25, 0.26
    and 0.27, with a packing factor of 1.12 by
    maintaining the constant proportions of Cement,
    Micro Silica, VMA, Coarse aggregate and Fine
    aggregate.
  • The mix proportions of the concrete used in this
    study are shown in Table 8.
  • The typical mix design calculation is shown in
    Table 8A.

39
Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios Table 8.0 Mix proportions of concrete containing different water-binder ratios
Mix Constituents Mix Designation Mix Designation Mix Designation Mix Designation Mix Designation Mix Designation Mix Designation Mix Designation Mix Designation Mix Designation
Mix Constituents M1 (W/C0.23) M1 (W/C0.23) M2 (W/C0.24) M2 (W/C0.24) M3 (W/C0.25) M3 (W/C0.25) M4 (W/C0.26) M4 (W/C0.26) M5 (W/C0.27) M5 (W/C0.27)
Mix Constituents Qty. (kg/m3) Prop. Qty. (kg/m3) Prop. Qty. (kg/m3) Prop. Qty. (kg/m3) Prop. Qty. (kg/m3) Prop.
Cement 574 1 574 1 574 1 574 1 574 1
Fly Ash 41.00 0.071 34.30 0.06 27.60 0.05 20.90 0.04 14.20 0.02
Micro Silica 40.18 0.07 40.18 0.07 40.18 0.07 40.18 0.07 40.18 0.07
Fine Aggregate 844.48 1.47 844.48 1.47 844.48 1.47 844.48 1.47 844.48 1.47
Coarse Aggregate 805.32 1.4 805.32 1.4 805.32 1.4 805.32 1.4 805.32 1.4
Water to Binder ratio 140.68 0.229 143.82 0.236 146.97 0.244 151.18 0.254 153.25 0.261
Super Plasticizers 11.07 0.018 10.95 0.018 10.83 0.018 10.71 0.018 10.59 0.018
VMA 1.722 0.003 1.722 0.003 1.722 0.003 1.722 0.003 1.722 0.003
40
  • PREPARATION OF TEST SPECIMENS
  • A total of five batches for each mix based on the
    above mix proportions have been prepared.
  • The mixing process is done in electrically
    operated concrete mixer.
  • The predetermined quantities of fine and coarse
    aggregates are added to the mixer and mixed for
    thirty seconds.
  • After that the cement, fly ash and micro silica
    were added to the mixer and mixed together with
    the aggregates for one minute.

41
  • The various amounts of water, superplasticizer
    and viscosity admixture were added and mixed
    thoroughly.
  • This process of production was adopted for the
    whole quantum of work.
  • The mixes immediately after the preparation were
    used for carrying out the fresh concrete tests
    i.e., slump flow, V-funnel, L-box, U-box etc.
  • Sufficient number of cubes, cylinders and prisms
    were casted, cured and tested after the
    recognized ages to evaluate the properties of
    hardened concrete.

42
RESULTS AND DISCUSSIONS
  • TEST RESULTS ON FRESH CONCRETE
  • The workability tests i.e., Slump flow test,
    V-Funnel test, L-Box test and U-Box test results
    obtained for different water-cement ratios are
    presented in Table 9.
  • The graphical representations of water-cement
    ratio vs each of the workability tests are shown
    in Fig. 1 to Fig. 6.

43
Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC Table 9.0 Test Results on Fresh Concrete and Acceptance Criteria for SCC
S. No Method Unit Water/Cement Ratio Water/Cement Ratio Water/Cement Ratio Water/Cement Ratio Water/Cement Ratio EFNARC3 Specification Remarks
S. No Method Unit 0.23 0.24 0.25 0.26 0.27 EFNARC3 Specification Remarks
1 Slump Flow Test mm 655 660 665 680 700 SF1 550-650 SF2 660-750 SF3 760-850 SF2
2 T500 sec 3.94 3.88 3.82 3.32 2.50 VS1 T500 2 VS2 T500 gt 2 VS2
3 V-Funnel sec 8.50 8.35 8.10 7.95 6.89 VF1 8 VF2 9-25 VF2
4 T5min sec 11.89 10.92 10.66 10.23 9.95 VF1 8 VF2 9-25 VF2
5 L-Box h2/h1 0.950 0.959 0.969 0.975 0.980 PA1 gt 0.8 (2 rebars) PA2 gt 0.8 (3 rebars) PA2
6 U-Box mm 9 7 6 5 4 0-30 23 OK
44
Fig. 1. W/C Ratio vs Slump Flow
45
Fig. 2. W/C Ratio vs T500
46
Fig. 3. W/C Ratio vs V-Funnel
47
Fig. 4. W/C Ratio vs T5
48
Fig. 5. W/C Ratio vs L-Box Ratio
49
Fig. 6. W/C Ratio vs U-Box
50
  • TEST RESULTS ON HARDENED CONCRETE
  • The strength tests i.e., compressive strength,
    split tensile strength and flexural strength test
    results on hardened concrete at the age of 7 days
    and 28 days obtained for different water-cement
    ratios are presented in Table 10.
  • The graphical representations of water-cement
    ratio vs each of the strength tests are shown in
    Fig. 7 to Fig. 9.

51
Table 10.0 Test Results on Hardened Concrete Table 10.0 Test Results on Hardened Concrete Table 10.0 Test Results on Hardened Concrete Table 10.0 Test Results on Hardened Concrete Table 10.0 Test Results on Hardened Concrete Table 10.0 Test Results on Hardened Concrete Table 10.0 Test Results on Hardened Concrete
Concrete Mix Compressive Strength (N/mm2) Compressive Strength (N/mm2) Split tensile Strength (N/mm2) Split tensile Strength (N/mm2) Flexural Strength (N/mm2) Flexural Strength (N/mm2)
Concrete Mix 7days 28days 7days 28days 7days 28days
M1 (W/C0.23) 61.64 82.22 3.72 4.09 5.92 6.76
M2 (W/C0.24) 59.73 82.07 3.63 4.08 5.84 6.52
M3 (W/C0.25) 53.11 81.62 3.43 4.05 5.72 6.20
M4 (W/C0.26) 52.53 81.29 3.40 3.99 5.46 5.86
M5 (W/C0.27) 52.48 80.53 3.37 3.89 5.18 5.69
52
Fig. 7. W/C Ratio vs Compressive Strength
53
Fig. 8. W/C Ratio vs Split Tensile Strength
54
Fig. 9. W/C Ratio vs Flexural Strength
55
  • DISCUSSION ON TEST RESULTS
  • Based on the above experimental results, the
    observations are as follows
  • Slump flow increases with the increase of
    water/cement ratio.
  • T500 time, V-funnel time, T5 time and U-box
    values are decreases with the increase of w/c
    ratio.
  • L-box value increases with the w/c ratio.
  • All the workability test results are well in
    comply with the EFNARC specifications of SCC and
    acceptance criteria are shown in Table 9.

56
  • Compressive strength, tensile strength and
    flexural strengths are decreasing as the w/c
    ratio increases.
  • Marginal increase in the compressive strength at
    28 days of concrete as the w/c ratio decreases.
  • Compressive strength and split tensile strength
    decreases at higher rate for 7 days strength when
    compared to 28 days strength, whereas it is also
    observed that flexural strength value decreases
    at higher rate for 28 days strength when compared
    to 7 days strength.
  • The variation of decrease in strengths at 7
    days and 28 days with w/c ratios are shown Fig.
    10 to Fig. 11.

57
Fig. 10. W/C Ratio vs Decrease in Strength at 7
days
58
Fig. 11. W/C Ratio vs Decrease in Strength at
28 days
59
CONCLUSIONS
  • All the mixes used in this study exhibits the
    good workability characteristics, in accordance
    with the EFNARC specifications.
  • Workability characteristics i.e., passing
    ability, filling ability and segregation
    resistance of the SCC mixes are linearly
    increasing with the increase of water-cement
    ratio.
  • It is observed that the w/c ratio increases, the
    compressive strength decreases by 14.9, split
    tensile strength decreases by 9.4 and flexural
    strength decreases by 12.5 at 7 days age of
    concrete.

60
  • It is observed that as the w/c ratio increases,
    the compressive strength decreases by 2.1, split
    tensile strength decreases by 4.9 and flexural
    strength decreases by 15.8 at 28 days age of
    concrete.
  • It is observed that compressive strength and
    split tensile strength decreases at higher rate
    for 7 days strength when compared to 28 days
    strength, whereas it is also observed that
    flexural strength value decreases at higher rate
    for 28 days strength when compared to 7 days
    strength.

61
  • Therefore from the experimental results, the
    compressive strength, split tensile strength and
    flexural strength decreases as the w/c ratio
    increases.
  • With these experimental results, all the mixes
    were able to develop a higher strength concrete
    without any vibration, with complies all the
    workability requirements of SCC.
  • The relation between the strengths and water
    cement ratios, flow values and water cement
    ratios are almost linear.

62
  • Scope of Future Work
  • The present investigation will be extended to the
    more number of concrete strength ranges and also
    on the structural elements i.e., beams and slabs
    etc..
  • The investigation may be extended to the alkaline
    and thermal effects.
  • The investigations may be extended with different
    proportions and different types of mineral
    admixtures apart from fly ash and silica fume.

63
  • PHOTOGRAPHS

64
SPECIMENS DURING CASTING
65
SPECIMENS DURING CASTING
66
SPECIMENS DURING CURING
67
SPECIMENS DURING TESTING
68
SPECIMENS DURING TESTING
69
SLUMP FLOW TEST
70
V FUNNEL TEST
71
L-BOX TEST
72
REFERENCES
1. C. Selvamony, M. S. Ravikumar, S. U. Kannan and S. Basil Gnanappa, Development of High Strength Self Compacting Self Curing Concrete using Lime Stone Powder and Clinkers, ARPN Journal of Engineering and Applied Sciences, Vol. 5, No. 3, March 2010.
2. Dr. Hemant Sood, Dr.R.K.Khitoliya and S. S. Pathak, Incorporating European Standards for Testing Self Compacting Concrete in Indian Conditions, International Journal of Recent Trends in Engineering, Vol. 1, No. 6, May 2009, pp. 41-45.
3. EFNARC (The European Federation of Specialist Construction Chemicals and Concrete Systems), The European Guidelines for Self Compacting Concrete Specification, Production and Use, SCC 028, May 2005.
4. Hajime Okamura, Masahiro Ouchi, Self-Compacting Concrete, Journal of Advanced Technology, Vol. 1, No. 1, April 2003, pp. 5-15.
5. IS 383-1970, Specification for Coarse and Fine Aggregate from Natural Sources for Concrete, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
IS 456-2000, Plain and Reinforced Concrete-Code of Practice, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
7. IS 516-1959, Methods of Test for Strength of Concrete, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
8. IS 2386 (Part-I)-1963, Methods of Test for Aggregate for Concrete, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
9. IS 3812-1981, Specification for Fly Ash for Use as Pozzolana and Admixture, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
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10. IS 5816-1999, Method of Test for Splitting Tensile Strength of Concrete Cylinders, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
11. IS 9103-1989, Concrete Admixtures-Specification, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
12. IS 12269-1987, Ordinary Portland Cement 53 Grade-Specification, Bureau of Indian Standards, Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi-110 002.
13. Kazim Turk, Mehmet Karatas, and Tahir Gonen, Effect of Fly Ash and Silica Fume on Compressive Strength, Sorptivity and Carbonation of SCC, KSCE (Korean Society of Civil Engineers) Journal of Civil Engineering, Vol. 17, No. 1/January 2013, pp 202-209.
14. Nan Su, Kung-Chung Hsu, His-Wen Chai A simple mix design method for self-compacting concrete, Cement and Concrete Research 31 (2001), pp. 17991807.
15. N. R. Gaywala and D. B. Raijiwala, Self Compacting Concrete A Concrete of Decade, Journal of Engineering Research and Studies, JERS/Vol. II/ Issue IV/October-December, 2011/213-218.
16. Nguyen, T.L.H., Roussel, N. and Coussot, P. Correlation between L-box test and rheological parameters of a homogeneous yield stress fluid, Cement and Concrete Research, 36, 2006, pp. 1789-1796.
17. Okamura, H., Self Compacting High Performance Concrete, ACI Concrete International, Vol. 19, No. 7, July 1997, pp. 50-54.
18. P. A. Ganeshwaran, Suji, S. Deepashri, Evaluation of Mechanical Properties of Self Compacting Concrete with Manufactured Sand and Fly Ash, International Journal of Civil Engineering and Technology (IJCIET), Volume 3, Issue 2, July- December (2012), pp. 60-69.
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19. PCI (Precast/Prestressed Concrete Institute), Interim Guidelines for the use of Self Consolidation Concrete in Precast/Prestressed Member Plants, TR-6-03, April 2003.
20. Paratibha Aggarwal, Rafat Siddique,Yogesh Aggarwal, Surinder M Gupta Self-Compacting Concrete- Procedure for Mix Design, Leonardo Electronic Journal of Practices and Technologies, Issue 12, January-June 2008, pp. 15-24.
21. Prof. Kishor S. Sable, Prof. Madhuri K. Rathi, Comparison of Self Compacted Concrete with Normal Concrete by Using Different Type of Steel Fibres, International Journal of Engineering Research Technology (IJERT), Vol. 1, Issue 6, August 2012.
22. Prof. Shriram H. Mahure, Mayur B. Vanjare, Experimental Investigation On Self Compacting Concrete Using Cement Kiln Dust, International Journal of Engineering Research Technology (IJERT) Vol. 2 Issue 1, January- 2013.
23. Shetty, M.S., (2002), Concrete Technology, Theory and Practice, Chand, S. and Company Limited, Ramnagar, New Delhi 110 055.
24. Soo-Duck Hwang, Kamal H. Khayat, and Olivier Bonneau, Performance-Based Specifications of Self-Consolidating Concrete Used in Structural Applications, ACI Materials Journal/March-April 2006, pp. 121-129.
25. S. Venkateswara Rao, M. V. Seshagiri Rao and P. Ratihish Kumar, Effect of size of aggregate and fines on standard and high strength self-compacting concrete, Journal of Applied Science Research, 2010, 6(5) 433-442.
26. Wu, Z., Zhang, Y., Zheng, J. and Ding, Y., An experimental study on the workability of self-compacting lightweight concrete, Construction and Building Materials, 23, 2009, pp. 2087-2092.
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