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International Journal of Advanced Engineering Research and Technology (IJAERT)Volume 2 Issue 1, April 2014, ISSN No.: 2348 – 8190

www.ijaert.org

Studies on fatigue characteristics of cement concrete made with demolished

concrete wastes

Srikanth.M.Naik 1, Kamalakara G.K2, Suresh Kumar K.S3

1Professor, M.S.RamiahInstitute of Technology, Bangalore, Karnataka, India

2

Assistant professor, RajarajeswariCollege ofEngineering, Bangalore, Karnataka, India3Research Scholar, Department of Civil Engineering, Bangalore University, Bangalore, India

ABSTRACTThe interest in the utilization of concrete waste materials

such as aggregate and mortar is increasing, with the

prospect of becoming a widely diffused Product in the

near future. Therefore new researches on these materials

have raised the interest of the scientific medium and also

construction industry sector.Billions of tons of concrete

have been used to construct buildings, bridges, dams,roads and other structures. When the useful life of these

structures is over, the materials from which they were

built will find their way into the waste stream as rubble.

Landfills are becoming increasingly difficult to find. At

the same time sources of supply of suitable aggregate for

making concrete are continually being exhausted. The

recycling of building demolition waste materials into

new applications in civil engineering work can provide a

solution to these problems.In view of the above, an

attempt has been made to study the fatigue

characteristics of concrete made with waste mortar

aggregates as a replacement of fine and coarseaggregate.

 Keywords- Fatigue, flexure, demolished concrete waste,

aggregates, waste mortar 

I. INTRODUCTIONDemolition waste is the solid waste generated by the re-

modeling, renovation, repair, alteration or demolition of 

residential, commercial, government or institutional

buildings, industrial or commercial facilities, roadways

and other engineering structures. Waste generation is a

good indicator of the unsuitable practices associatedwith our lifestyle and development activities. Until

recently, the common way to manage waste was to bury

it without any processing. However, there is significant

room for improvements to waste management practices

to minimize the waste reaching the landfill sites.

 A. Research significance

Very little literature has been reported on research which

addresses the behavior of concrete made by demolished

waste concrete under static and flexural fatigue loadingIn this paper investigations are conducted on fly ash

concrete and concrete prepared by adding demolished

aggregates and mortar. Log-normal distribution is

generally considered for developing S- N curve to

determine the number of repetitions to failure undefatigue loading.

II. MIX PROPORTIONS AND

STRENGTHS OF CONCRETE MIXOrdinary Portland Cement- 43 grade and class- F fly ash

are used as binders, 20mm and downgraded crushed

granite stone coarse aggregates, recycled aggregates

mortar and river sand conforming to IS 383-1970 are the

materials used in this study. The mix proportions areshown in Table 1. Percentage of aggregates used is

shown in Table 2.Compressive and flexural strength

tests are carried out as per IS 516-1959. Cube specimen

of size 150mm X 150mm X 150 mm are cast and testedto determine compressive strength. Prisms of size100mm X 100mm X 500 mmare cast and static flexural

tests conducted to determine the static failure loads on

the specimen. Compressive and flexural strengths

obtained are shown in Table 3.

TABLE 1 MIX PROPORTIONS OF CONCRETE

MIXES

MixM1

kg/ m3M2

kg/ m3M 3

kg/ m3M 4

kg/ m3

M 5

kg/ 

m3

Cement 268 268 268 268 268Fly ash 30 30 30 30 30

Fine

aggregate765 825 844 804 786

Coarse

aggregate934 850 881 908 969

Water

content236 258 230 235 205

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International Journal of Advanced Engineering Research and Technology (IJAERT)Volume 2 Issue 1, April 2014, ISSN No.: 2348 – 8190

www.ijaert.org

TABLE 2. PERCENTAGES OF AGGREGATES USED

MIX M1 M2 M3 M4 M5

Natural

Aggregates (%)0 0 100 50 100

Recycled

Aggregates (%)100 100 0 50 0

Fine Aggregates

(sand) (%)100 0 0 50 100

Fine Aggregates(mortar) (%)

0 100 100 50 0

TABLE 3. COMPRESSIVE AND FLEXURAL

STRENGTHS

MIX M1 M2 M3 M4 M5

Compressive

strength(MPa)

25 21.51 23.25 26.74 31.10

Flexural

strength(MPa)

2.18 3.87 4.03 2.50 4.27

Prism specimen are loaded and tested in accordance withASTM test method C 78. The third point loading method

with forces applied perpendicular to the beam withou

eccentricity is adopted. Accelerated cyclic fatigue testing

equipment is used to conduct flexural fatigue test. The

schematic diagram of the test arrangement is showed inFigure 1and a snap shot of the test set up is shown in

Figure 2. To simulate realistic traffic loading half sine

wave form loading with a frequency of two cycles per

second is applied repetitively on the specimen.

From the experimental studies carried out using the

accelerated fatigue testing equipment, the numbers of

repetitions to failure are determined for each tes

specimen at three stress levels 0.65, 0.75 and 0.85 for al

the mixesM1, M2, M3, M4 and M5.

FIGURE 1FLEXURAL FATIGUE TEST ARRANGEMENT

FIGURE 2FLEXURAL FATIGUE TEST SET UP

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International Journal of Advanced Engineering Research and Technology (IJAERT)Volume 2 Issue 1, April 2014, ISSN No.: 2348 – 8190

www.ijaert.org

III. ANALYSIS OF FATIGUE TEST DATAFrom the fatigue test data obtained for the five concretes

under investigation S-N curves are developed using

linear regression models, considering log normal

distribution. The linear regression model is of the form(y = ax + c) in which stress ratio (S) is taken on Y-axis

and Log (N) values are taken on the X-axis. The scatter

diagram of the test results for M1, M2, M3, M4 and M5

concretes are shown in Figure 3. The linear relationship

obtained from the trend lines for M1, M2, M3, M4 and

M5 concretes along with the R2 values are shown in

equations 1, 2, 3, 4&5.

FIGURE 3 SCATTER DIAGRAM

Log (N) = M1……….1

R² = 0.21

Log (N) = M2……….2

R² = 0.24

Log (N) = M3……….3

R² = 0.56

Log (N) = M4……….4

R² = 0.23

Log (N) = M5……….5

R² = 0.55

IV. DISCUSSIONS AND CONCLUSIONSThe results presented in Table 2 show that the 28 day

cube compressive strengths decrease with increasing

percentages of waste aggregates and mortar. Howeve

the target mean strength is achieved in all the specimens

Thus cement concretes made with demolished concrete

aggregates can be used in infrastructures, which need

compressive strength upto 20MPa and also in pavements

as dry lean concrete in sub bases.

It can be observed from table 2 that the maximumflexural strength is obtained for mix M5 (i.e. natura

aggregates and sand). Table 2 also shows better flexura

strength in M2 and M3 mixes, whensandis replaced by

mortar.

Five fatigue models are also developed in this study

These fatigue models can be used for estimating the

cumulative fatigue life of cement concrete that are

madeusing demolished concrete.

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International Journal of Advanced Engineering Research and Technology (IJAERT)Volume 2 Issue 1, April 2014, ISSN No.: 2348 – 8190

www.ijaert.org

Thus it can be concluded that recycling waste from the

construction industry achieves the objective of 

sustainable development.

REFERENCES

[1]Yanagi K., Nakagawa. M, Hisaka Kasai.Y, “Effect of impurities in Recycled coarse aggregate upon A few

 properties of the concrete”, volume 2, reuse of 

demolition waste, proceedings of second international

symposium held by RILEM(1988).[2] Tarun R. Naik,.Malhotra V.M, Shiw S. Singh, and

Bruce W. Ramme.”Flexural Fatigue Strength of HVFAConcrete Systems” Report No. CBU-1997-25 November

1997.

[3] M. Heeralal, P. Rathish Kumar and Y.V. Rao

“Flexural Fatigue Charecteristics of Steel Fiber Reinforced Recycled Aggregate Concrete FACTA

UNIVERSITATIS Architecture and Civil EngineeringVol. 7, N, 2009, pp. 19 – 33.

[4] ACI 215R 74, 1997 Considerations for Design of Concrete Structures Subjected to Fatigue Loading.

[5] IRC 58 2011, Guidelines for the design of plain

 jointed rigid pavements for highways.