International Journal of Scientific & Engineering Research, Volume 6, Issue 4, April-2015 199

ISSN 2229-5518

An Experimental Study on Compressive Strength of Various Cement Concrete Under Sea Water

Swati Maniyal, Ashutosh Patil

Abstract— Potable water is becoming a scarce commodity on this planet Earth with time. Hence, we need to find alternatives for potable water as billons of liters of water is used in construction industry. This research work seeks to investigate the use of sea water as mixing and curing of concrete as 97% of the water on Earth surface is sea water. For this concrete cubes were cast for a design mix of M-20,

1:1.777:2.826 by weight and 0.47 water cement ratio and M-25, 1:1.432:2.472 by weight and 0.414 water cement ratio using OPC 43

grade, OPC 53 grade and PPC cement as per guidelines for concrete mix proportioning with a slump of 75 mm to 100 mm. Half of the cubes were cast and cured with potable water and half with sea water. The cubes were cast and cured for 7, 14, 21, 28 days and was tested for compressive strength. From the results it was found that compressive strength increases during initial days of curing when cubes are cast and cured in sea water but finally characteristic strength decreases by about 5% as compared to cubes cast and cured with potable water.

Keywords—Compressive strength, concrete cubes, curing, design mix, mixing, potable water, sea water.

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1 INTRODUCTION

Concrete is one of the most common and widely used construction materials due to its strength and durability properties. It is all most impossible to find an alternative for concrete. It is an artificial material made from the mixture of cement, aggregate, sand, admixtures and water to form a uniform plastic material which sets gradually and gains strength with time.
The strength of concrete depends on the concrete mix, method of curing, water cement ratio, aggregates and cement types. Water is an important ingredient of concrete as it participates in the chemical reaction with cement. According to the literatures available, it is said that in 2025, the half of the world will not have water even for daily necessities. Globally, billon of tons of water is used for concreting. In order to save water we are trying to investigate the usage of sea water as mixing and curing for concrete. It is important to investigate the possibility of usage of sea water in construction industry as
97% of the total water on Earth is sea water. Also, United Nations (UN) and World Metrological Organization (WHO) have predicted that 5 billion people will be in short of even drinking water. So, there is a need to explore alternative for potable water in construction industry. A large number of structures are exposed to seawater either directly or indirectly. Thus, possibility of usage of sea water in concrete is studied.
In the present study, concrete with various types of cement
viz; Ordinary Portland Cement (OPC) 43 Grade, Ordinary
Portland Cement (OPC) 53 Grade, Pollozona Portland cement
(PPC), is adopted. Concrete grades of M-20 and M-25 design
mix with a slump in between 75 to 100 mm were considered in
the study. The exposure conditions of “Concrete mixing and
curing with potable water ” and “Concrete mixing and curing
with sea water” are adopted.

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• Swati Maniyal is currently pursuing Master’s Degree program in Structural Engineering in N.B.N.S.C.O.E; Solapur University, India, PH-9890323027. E-mail: swati.maniyal@gmail.com

• Ashutosh Patil is currently working as an Assistant Professor in in

N.B.N.S.C.O.E; Solapur University, India, PH-9403688721. E-mail:

er.ashutoshpatil@gmail.com

2 NECESSITY OF PROJECT

Predications say that in near future there will be shortage of drinking water. Hence, fresh water will not be available for concreting purpose. We use bore water for mixing as well as curing of concrete instead of fresh water. The bore water available is neither free from impurities nor is considered as soft water. There are number of salts presents in bore water which results in hardness. Here in this research work we are working on the effect of sea water as mixing and curing on concrete. We test the concrete for extreme case i.e. sea water case.

3 LITERATURE REVIEW

According to Water Encyclopaedia (2012), great bodies of water covers about five seventh of the earths’ surface about 71 percent in some places to depth more than ten kilometres. Adebakin, H. I. (2003) describes fresh water as purified water which is free from impurities. Akinkurolere O.O et.al (2007) said sea water is a complex solution of many salts containing living matter, suspended silt, dissolved gases and decaying organic material. The average salt concentration of sea water is about 3.5% depending upon its location. The primary chemical constituents of seawater are the ions of chloride, sodium, magnesium, calcium and potassium. The concentration of major salt constituents of seawater we are given in weight % of salt as 78%NaCl, 10.5% MgCl2 , 5% MgsSO4 , 3.9% CaSO4 ,
2.3% K2SO4 and 0.3% KBr.
Studies were conducted during past on effect of mixing and
curing of sea water in concrete. Falah M. Wegian (2010)
investigated the effects of mixing and curing concrete with sea
water on the compressive, tensile, flexural and bond strengths
and reported that there are increases of strengths of concrete
mixed and cured in sea water at early ages and a definite
decrease for ages more than 28 days and up to 90 days.

Donald F. Griffin et.al (1964) concluded that a small amount

of sea-water salts may be to concrete if rigid controls are
exercised. Maximum compressive strength occurs between
salinities of 18 and 36 gm/kg for concrete incorporating NaCl

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International Journal of Scientific & Engineering Research, Volume 6, Issue 4, April-2015 200

ISSN 2229-5518

in the mixing water. Depending upon the age of concrete, relatively high salinities of NaCl can occur before strengths become less than those for zero salinity. Natural sea water does not deteriorate plain concrete; strength is generally increased with salinities up to nearly three times that of natural sea water. Nobuaki Otsuki et.al (2011) concluded from the test results and discussions and are confident to safely use sea water as mixing water. P. Krishnam Raju et.al (2014) concluded that there is no reduction in compressive strength due to mixing and curing of sea water, whereas the average compressive strength arrived for designated concretes are more than the target strength. O.O. Akinkurolere et.al (2007) concluded that concrete cast with sea water and cured with sea water increases the 28 days compressive strength dramatically and linearly beyond that obtained when cast in fresh water and cured in fresh water. Preeti Tiwari et.al (2014) performed series of experiments on M-30 grade and said that there is marginal increase in the strength of cubes cast and cured in salt water as compared to those of cast and cured in fresh water at all ages of curing and concluded that there is no reduction in the strength if we use salt water casting and curing the concrete. K. J. Kucche et.al (2015) quoted that from stream, river and even sea is also suitable, if it not contain brackish matter. Tarek Uddin Mohammed et.al said that seawater-mixed concrete shows earlier strength gain compared to the tap water-mixed concrete. However, after a long-term of exposure, no significant difference in compressive strength is observed.

4 MATERIALS AND METHODOLOGY

4.1 Materials

The detail of various materials used in the experimental investigation will be:
• Coarse Aggregate:-Crushed granite stone aggregate of maximum size 20 mm confirming to IS 383-1970 was used. The specific gravity was found to be 2.925.
• Sand (Fine Aggregate):- The fine aggregate used was sand passing through 4.75 mm sieve. The specific gravity was found to be 2.83. The grading zone of fine aggregate was zone I as per IS specification.
• Cement:- OPC 43 grade, OPC 53 grade, PPC (Ultratech Cement) was used.
• Water:- Ordinary clean potable water free from suspended particles and chemicals was used for mixing and curing of concrete.
• Sea water:-Seawater is water from a sea or ocean.
Here sea water from Arabian Sea was used.

4.2 Methodology

Experimental Procedure: To investigate the effect of sea water on compressive strength of concrete, half of the concrete cubes were cast and cured with potable water and half of the concrete cubes were cast and cured with sea water.

The concrete cube size measuring 150×150×150 mm in dimension will be used. The batching of the concrete was carried out by weight. The mix proportion was calculated for characteristic compressive strength of 20 N/mm^2 and M-25
N/mm^2. The concrete was properly mixed using the sea
water and potable water respectively, the concrete cubes mould were filled in three layers. In each of the layer, the concrete cubes will be compacted 25 times respectively. The concrete cubes were cast and cured for 7, 14, 21 and 28 days and will be tested for compressive strength.

Workability: Workability of cubes mixed with sea water and potable water are measured separately before casting of cubes. The workability maintained was medium i.e. slump was maintained between 75 mm to 100 mm for mass concrete.

Compressive Strength: The compressive strength is taken as maximum compressive load resisted by per unit area. The test specimens for the determination of compressive strength of concrete were prepared using the standard metallic cube mould. The concrete cube mould were lubricated with oil before the mixed concrete was placed inside it, in order to reduce friction between the concrete and the cubes.

The cubes are demoulded after 24 hour of casting, and cured in water having similar quality as used in the preparation of mix. For each of the curing period of 7, 14, 21 and 28 days, cubes were tested and the average compressive strength recorded.

Test Results: After casting and demoulding, the sea water concrete cubes has a darker surface than the reference concrete cubes, when cured in sea water a deposit of salt formed on a specimens. The concrete cubes were tested in “Compression Testing Machine of Technical and Scientific Sales Instruments” which has a capacity 200 tones. The tests were carried out at “Vidya Vikas Pratishthan (VVP) Polytechnic, Solapur”.

Results indicate that, that compressive strength increases during initial days of curing when cubes are cast and cured in sea water but finally characteristic strength decreases by about
5% as compared to cubes cast and cured with potable water.

TABLE 1

QUANTITIES FOR 12 CUBES, M-20

TABLE 2

QUANTITIES FOR 12 CUBES, M-25

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TABLE 3

TEST RESULTS FOR M-20 (OPC 43 GRADE)

(Laboratory: VVP Polytechnic, Solapur)

TABLE 4

TEST RESULTS FOR M-20 (OPC 53 GRADE)

(Laboratory: VVP Polytechnic, Solapur)

TABLE 5

TEST RESULTS FOR M-20 (PPC)

(Laboratory: VVP Polytechnic, Solapur)

TABLE 6

TEST RESULTS FOR M-25 (OPC 43 GRADE)

(Laboratory: VVP Polytechnic, Solapur)

TABLE 7

TEST RESULTS FOR M-25 (OPC 53 GRADE)

(Laboratory: VVP Polytechnic, Solapur)

TABLE 8

TEST RESULTS FOR M-25 (PPC)

(Laboratory: VVP Polytechnic, Solapur)

Fig. 1. Average Compressive Strength of M-20 Concrete

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Fig. 2. Average Compressive Strength of M-25 Concrete

Fig. 4. Graphical Representation of Average Compressive Strength of

M-20 and M-25 Concrete Using OPC 53 Grade

Fig. 3. Graphical Representation of Average Compressive Strength of M-20 and M-25 Concrete Using OPC 43 Grade

Fig. 5. Graphical Representation of Average Compressive Strength of

M-20 and M-25 Concrete Using PPC

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5 CONCLUSIONS

1. Series of experiments were conducted on M-20 and

M-25 grade of concrete using OPC 43 grade, OPC

53 grade and PPC. From the results it can be said

that, there is an increase in the of compressive

strength of concrete cubes at early ages which were

cast and cured with sea water as compared with

the concrete cubes cast and cured with potable

water. The strength increases by 4-8% at 7 days and

9-13% at 14 days.

2. There is no remarkable reduction in compressive

strength due to mixing and curing of sea water, the

strength decreases by about 1-5% at 28 days when

concrete is mixed and cured with sea water as

compared to characteristic target strength when

concrete mixed and cured with potable water.

3. The reduction of strength percentage is most for

PPC and least for OPC 53 grade for both M-20 and

M-25 grade of concrete.

4. Studies may be carried out for higher grades of

concrete i.e. M-30 and above and other types of

cements, other types of admixtures and ground

granulated blast furnace slag cements etc.

From the above finding we can conclude that there is

no remarkable variation in the compressive strength if

sea water is used for casting and curing the concrete.

This concrete can be safely used for mass concreting

without any alteration in strength properties.

6 REFERENCES

[1] Swati Maniyal, Ashutosh Patil, “An Experimental Review of Effect of Sea Water on Compressive Strength of Concrete”, International Journal of Emerging Technology and Advance Engineering (IJETAE), Vol. 5, Issue 3, pp 155-159.
[2] IS 10262-2009, “IS 10262-2009, “Concrete Mix
Proportioning”
[3] P. Kumar Mehta & Paulo J.M. Monteiro. “Concrete in
Sea Water ”, Concrete Microstructure, Properties and
Materials.
[4] Building research Station (1956). “Analysis of water encountered in construction”, Digest No. 90, London, H.M.S.O.
[5] Donald F. Griffin and Robert L. Henry (1964). “The Effect of Salt in Concrete on Compressive Strength, Water Vapour Transmission and Corrosion of Reinforcing Steel”, U.S. Civil Engineering Laboratory, California,
[6] Osei, Y. A. (2000). “Neutralization, New School
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[7] Adebakin, H. I. (2003). “Effect of Salinity on
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[8] Akinkurolere O.O. et.al. (2007). “The Influence of Salt
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[9] Water Encyclopaedia (2012). “Earth: The water
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[10] Falah M. Wegian (2010). “Effects of sea water for
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[11] P. Krishnam Raju, V. Ravindra and M. Bhanusingh
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[12] Preeti Tiwari, Rajiv Chandak, R.K. Yadav (2014),

“Effect Of Salt Water On Compressive Strength Of
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[13]Takahiro Nishida1, Nobuaki Otsuki, Hiroki Ohara,

Zoulkanel Moussa Garba and Tomohiro Nagata,
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