STUDY ON STRENGTH BEHAVIOUR OF CONCRETE BY PARTIAL

REPLACEMENT OF COARSE AGGREGATE BY RIVER PEBBLES AND FINE

AGGREGATE BY QUARRY DUST

M.DHIVYA

R.SUBBULAKSHMI

GUIDE NAME : Mr. V.THIRUMURUGAN

IFET COLLEGE OF ENGINEERING

VILLUPURAM

ABSTRACT:

Concrete is most widely and commonly used in construction. The raw material production of concrete has

certain harmfull effects on environmental. The aggregate element in concrete occupy 60-70% of the total volume. So

that the production of fine and coarse aggregate demand is increased now days. The aim of our project is to

overcome the demand of the raw materials. This is an urgent need to find alternative or green materials of concrete

to preserve and protect our natural resources for future, by replacing them partially or fully to achieve sustainable

development in concrete industry. This paper is mainly discusses the naturally available river pebbles, quarry dust

as partial replacement of coarse and fine aggregates. The study evaluates the strength of hardened concrete by

partially replacing coarse and fine aggregates by various percentages for M30 grade of concrete. Concrete mixes

with 0%, 10%, 20%, 30% replacement of river pebbles and quarry dust in our study. The mix proportion is done as

per IS: 10262-2009 and IS 456-2000. The properties of fresh and hardened concrete were studied on the mixes

considered. The results showed that strength properties and hence the use of river pebbles could be considered for

future concrete.

Keywords: River pebbles, Quarry dust, coarse aggregate, fine aggregate.

INTRODUCTION:

Concrete is one of the major construction

material being utilized worldwide. Concrete

is made usually by proper proportioned

mixer of cement, fine and coarse aggregate.

Continuous extraction of sand from river

causes environmental issues, along this

email issues the cost of the sand is

increased. To overcome these problems the

usage of an alternative material has required.

The place where the pebbles are largely

found must be identified and can be used to

replace the river sand since they give much

positive results when compared to other

alternative material. The reuse of the

pebbles will help to save cost conserve

limited resources and ultimately protect the

environment. Due to heavy increase in

construction activities, the crushed granite

stone which are the conventional coarse

aggregate is under depletion thus causing

shortage. The sand activities have resulted in

large number of environmental and social

problems. To meet the global demand of

concrete in the future, it is becoming a

challenging task to find suitable alternative

construction materials which can fully or

partially replace the natural aggregate

without affecting the property of concrete

make green concrete for sustainable future.

In India almost civil engineering

construction are carried out using coarse

aggregate. Due to heavy increase in the

construction activities, the crushed granite

stone which are the conventional coarse

aggregate is under depletion and also, now-

a-days on acute shortage of this material is

experienced. The strength of the concrete is

determined by replacing the main concrete

ingredients with alternative materials in

various percentages for M30 mix.

MATERIALS USED:

The cement used in Portland

Pozzalonic cement grade 43,specific gravity

was 3.15 and fineness was 4%. Locally

available river sand as fine aggregate size of

4.75mm to 75 micron was used. The sand is

free from organic impurities. The quarry

dust fine 4.75mm to 75 micron was used for

partial replacement to natural sand. Both

fine aggregate, natural and manufactured

sand were from zone II. The machine

crushed angular coarse aggregate of 20mm

and 10mm nominal size from the local

source of granite. It is free from dust clay

particles and organic matter. Rive pebbles

size varies from 10mm to 30mm were used.

The pebbles were found in natural sand after

sieving. The physical properties of raw

materials described followings.

FINE AGGREGATE

COARSE AGGREGATE

TABLE 1- Physical properties of aggregate

Description

of

materials

Specific

gravity

Water

absorption

Impact

value

Bulk

Density

(gm/cc)

CA,20mm

3.22

0.44

10.5

1.89

CA,20mm

3.16

0.29

10.7

1.95

River

pebbles

2.73

1.43

27.8

1.85

Coarse

2.84

1.77

-

2.05

Sand

quarry dust

2.79

1.9

-

2.33

METHODOLOGY:

1. INTRODUCTION:

The present investigation

and comparative studies on the strength

characteristics of river pebbles as coarse

aggregates and quarry dust as fine

aggregates in concrete with conventional

concrete was carried out. The standard test

of all materials has been carries out in the

laboratory as per the codes.

2. EQUIPMENT USED:

The following apparatus are used in the

present investigation.

1. Regular steel mould for cubes.

2. Table vibrator machine.

3. Compressive testing machine.

4. Slump cone apparatus.

5. Compacting factor apparatus.

6. Mixing tray, trowels, measuringjar,

weighing balance,etc.

MOULDS:

Cast iron moulds conforming to IS:

516-1959 were used to cast cube specimen

size of 150mm x 150mm x 150mm.

CONCRTE MIX:

M30 grade of concrete considered for this

study. Mix design was carried out according

to IS: 456:2000. The details of mix are

given in table 2. Various trial mixes are

considered for the study for the above grade

in table 3. The concrete was then placed in

standardcube moulds of size (150x150x150)

mm and thoroughly compacted using table

vibrator. The cube of each trial was then

kept for curing under water. The cubes of

each trial were tested for compression test

using compression testing machine after 7

days, 14days and 28 days of curing.

TABLE 2 MIX DETAILS:

TABLE 3 MIX DETAILS:

Trail Descriptions

1.

2.

3.

4.

Cement+FA+CA+Water

Cement+90% FA+90% CA+10% River

pebbles+10% Quarry dust+ Water

Cement+80% FA+80% CA+ 20% River

pebbles+20% Quarry dust+ Water

Cement+70% FA+70%CA+30% River

pebbles+30% Quarry dust + Water

Mix

Cement

Kg

Coarse

Aggregate

(Kg)

Sand

kg

River

pebbles

Quarry

dust

W/C

M30

385

1105

730

1085

700

0.5

TEST ON CONCRETE:

1. Test on fresh concrete: Slump test

Concrete mixes prepared where

tested for its fresh properties like

workability such as slump test. Slump test is

widely used to measuring the consistency of

the concrete. This test carried out by either

site or laboratory. The information of the

workability and quality of concrete can be

obtained by observing the manner in which

concrete slumps. The deformation

characteristics of the concrete with respect

to tendency and segregation.

2. Compacting factor test:

The compacting factor test is

designed primarily for use in the laboratory

but in can also be used in the field. In this

test is more sensitive then the slump test and

is useful for concrete mix of very low

workability as are normally used when

concrete is to be compacted by vibrations.

Such dry concrete are insensitive to slump

test.

3. Hardened concrete:

Testing of hardened concrete

plays on important role in controlling the

quality cement concrete work. The present

study the hardened properties such as

compressive strength are determined.

4. Compressive strength test:

The most common of all test is the

compressive strength test is the desirable

characteristics of the concrete are related to

the strength. The compressive test was

conducted on cubes at the age of 7 days, 28

days of curing respectively the conforming

to IS: 516-1959. The cubes are stored in

water were tested immediately on removal

from water in the damp condition. The

actual dimension and weight of the

specimen was noted. The specimen was

placed on the testing platform of the

compressive testing machine. In such way

the load was applied to the surface the cube

other than the top and bottom surface as

cast. The load was applied without shock

and increasesthe resistances of the specimen

to increasing the load broke down and no

greater load was sustained. The total load

applied at failure was recorded.

0

200

trail 1 trail 2 trail 3trail4

Slump cone test in

mm

60

130110 140

TABLE 4 –COMPRESSIVE STRENGTH

OF CONCRETE

The large amount of load applied by

crossessectional area giving the compressive

strength. They are taken the average of three

specimen, provided the individual variations.

CONCLUSION:

Based on these studies following

observations are made. The workability of

the concrete mix increase in the percentage

of river pebbles. This is mainly because of

the smooth surface and round shape of the

river pebbles. If the workability is constant,

the water content for some of the concrete

mixeshave been reduced. It is benefit to

improve the mechanical properties of

concrete.This help to reduce demand of fine

and coarse aggregate and also help to reduce

the environmental issues due to over

extraction of river sand.It also leads to

sustainable development of construction

industry in the most efficient way and also

addresses the high value of usage of such

alternatives.Even though the mechanical

properties of concrete is decreased using

river pebbles and quarry dust compared with

the standard aggregate concrete.Thus it can

be conclude that river pebbles and quarry

dust which is abundantly available locally

can be efficiently used as a coarse and fine

aggregate in concrete.

S.No

Trails

Compressive strength value

in N/mm2

7th

day

strength

28th

day

strength

1.

Nominal

20

35.8

2.

For 10%

23.4

34.5

3.

For 20%

38.7

42.5

4.

For 30%

21.3

38.6

REFFERENCE:

1.Chandra shekar.A, Maneeth. P.D Professor and HOD,

Department of Civil Engineering ,K.V.G College of Engineering-

Sully.

2. R.Sivakumar,Maduvanthi.D, Mohammed Yousuff.H,

Department of Civil Engineering- Coimbatore.

3.www.mineralzone.com

4. www.stonefinder.com

5. www.wikipedia.org

6. Akshy C. Sankh, “Recent trends in replacement of natual sand

with different Alternatives”, ISOR- JMCE.

7. IS: 2386-1963, (Part -I, III and IV)," Method of test for

aggregate test for Concrete", Bureau of Indian Standard, New

Delhi.

8. IS: 4031-1991, "Method of Physical Test for Hydraulic Cement"

9. IS: 1489 (PT1): 1991," Specification for PPC Part-I flyash'

10. Shetty M.S." Concrete Technology Theory and Practice

"Scand and company New Delhi.