Reduce of water in concrete

 
TOLANI FOUNDATION GANDHIDHAM POLYTECHNIC, ADIPUR - KUTCH

PROJECT
(3350609)
SEMESTER – V
BRANCH- CIVIL (GIA)

“REDUCE OF WATER IN CONCRETE”

GROUP MEMBERS
CHHANGA VIVEK – 166510306012
CHOTHANI HARIPRIY– 166510306014
DAVDA ANIKET – 166510306016
HADIYA HARSHIT – 166510306022
ZALAVADIYA BHARGAV– 176518306010

Project Incharge Head of department

Haresh Solanki Sir
Ravi Gurnani Sir
 CONTENT
CONCRETE
WATER
LITERATURE REVIEW
 NEED OF WATER FOR CONCRETE
WATER PROBLEMS
METHODS FOR REDUCING WATER IN
CONCRETE
EXPREIMENTAL SETUP
CONCLUSION AND REFRENCES
 CONCRETE
Concrete = Cement + Sand + Aggregates + Water +
Admixtures +Air.

 The mixture of cement and water is called paste .The

function of paste is to bind sand and aggregate particles by
the chemical process of hydration.

 It also fills the voids between sand and aggregate

particles. The strength of concrete depends upon the
properties of cement, sand, aggregates etc.
 WATER
• Source of water

The locations from where water can be available are called sources of water.

The distribution of water on the earth is as follows:

Seas and oceans...................... 97%
Ground water........................ ....2%
At poles as frozen ice............. 0.75%
Rivers and lakes..................... 0.25%
Total 100% Surface area occupied by land- 29% Surface area of earth
occupied by water 71%
 QUALITY OF WATER FOR CONCRETE

 Water used for mixing and curing shall be clean and free from injurious
amounts of oils, salts, acids, alkalis, sugar, organic materials. or other
deleterious materials.
 Average 28 days compressive strength of at least three 150 mm concrete
cubes prepared with water proposed to be used shall not be less than 90
percent of the average of strength of three similar concrete cubes prepared
with distilled water. The cubes shall be prepared, cured and tested in
accordance with the requirements of IS: 516.
 The initial setting time of test block made with the appropriate cement and
the water proposed to be used shall not be less than 30 min, and shall not
differ by +-30 min. from the initial setting time of control block prepared
with the same cement and distilled water
 WATER REQUIRMENTS FOR HYDRATION
 Amount of water required for chemical with Portland cement compounds is
given below.
Major compound % of water by weight of cement
C3S 24
C2S 21
C3A 40
C4AF 37

 It has been estimated that for C3S and C2S compounds , on an average 23 % of
water by weight of cement is required for chemical reaction. This 23% of water
chemically combines with cement and, therefore, it is called bound water. A certain
quantity of water is imbibed within gel-pores. This water is known as gel water. If
the quantity of water is inadequate to fill up the gel-pores, the formation of gel itself
will stop and if formation of gel stops there is no question of gel - pores being
present. Gel water of about 15 % by weight of cement is required. Therefore, a total
23 + 15= 38 % of water by weight of cement is required for complete hydration.
 If less than 38 % of water is used than complete hydration is not
possible as the volume available is insufficient to accommodate all
the products of hydration. Hence, strength of concrete will be
reduced.
 If more than 38 % of water is used, then the excess water will
cause undesirable capillary cavities and concrete becomes porous.
Therefore, greater the water above the minimum required is used
(38%), the more will be the undesirable capillary cavities. In all this it
is assumed that hydration takes place in a sealed container.
 LITERATURE REVIEW
 What is literature review

In the former two decades amount of research and development had been
done on Self Curing Concrete has led to a large and increasing number of
publications of all types. Those research papers are valuable for new
research in Self Curing Concrete. In this chapter those measured most
relevant to the existent study are reviewed and brief here.
(1)Mechanical properties of self-curing concrete (SCUC) Magda I.
Mousa,( Mohamed G. Mahdy,Ahmed H. Abdel-Reheem) 

 In this study, two materials were selected as self-curing agents with

different amounts,and the addition of silica fume was studied. The
self-curing agents were, pre-soaked lightweight aggregate (Leca);
0.0%, 10%, 15%, and 20% of volume of sand; or polyethylene-glycol
(Ch.); 1%, 2%, and 3% by weight of cement. To carry out this study
the cement content of 300, 400,500 kg/m water/cement ratio of 0.5,
0.4, 0.3 and 0.0%, 15% silica fume of weight of cement as an additive
were used in concrete mixes. The mechanical properties were
evaluated while the concrete specimens were subjected to air curing
regime (in the laboratory environment with 25 C, 65% R.H.) during
the experiment. The results show that, the use of self-curing agents in
concrete effectively improved the mechanical properties. The concrete
used polyethylene-glycol as self-curing agent, attained higher values
of mechanical properties than concrete with saturated Leca.
(2) Self Curing Concrete and Its Inherentproperties
(Stella Evangeline) 

 Proper curing of concrete structures is important to meet

performance and durability requirements. In conventional
curing this is achieved by external curing applied after
mixing, placing and finishing. Self-curing or internal curing
is a technique that can be used to provide additional moisture
in concrete for more effective hydration of cement and
reduced self desiccation It was found that water soluble
alcohols can be used as self curing agents in concrete. The
use of self-curing admixtures is very important from the
point of view that water resources are getting valuable every
day.
 NEED OF WATER FOR CONCRETE
 We needwater at two stages are following:

1. In mixing of concrete
2. In curing of concrete
 1. IN MIXING OF CONCRETE
 The aim of mixing of concrete is to produce homogenous,
consistent and uniform coloured concrete . This means that the
different constituents of concrete be uniformly distributed
throughout the concrete mass and the cement-water paste
should completely coat the aggregates.

 There are two methods of mixing concrete

(1) Hand mixing

(2) Machine mixing
 (1) Hand mixing

(2) Machine mixing

 2.IN CURING OF CONCRETE
 As discussed earlier, cement required a w/c ratio about 0.23 for
hydration and 0.15 for filling the gel pores. Hence, a w/e ratio of
0.38 would be required for complete hydration of hydration since
the concrete is open to atmosphere, the water used in the concrete
evaporates. However, it is seen that practically a higher w/c ratio of
about 0.5 is required for complete and the water available in the
concrete will not be sufficient for effective hydration.
PERIOD OF CURING
Specifications generally require that the concrete be kept moist for a period of at
least 7 days and preferably 14 days, when ordinary Portland cement is used. Rapid
hardening cements require less time (about half) and slow hardening cements
require more time, than ordinary Portland cement. When low heat cement is used,
the curing period must extend to 21 to 28 days.
 METHODS OF CURING
 The methods of curing to be adopted is depends upon the site
conditions, and the size, main shape and position of the
member to be cured.
1) WATER CURING:
 Water curing by far the easiest and most efficient of the
methods of curing and is extensively used.
 It consists in application water directly to the concrete or by
means of wet coverings of earth, sand, saw dust etc. Water
curing satisfies all the requirements of curing, namely
promotion of hydration, elimination of shrinkage and
absorption of the heat of hydration.
Water curing can be done in the following ways:

(1)Immersion (2)Ponding

(3)Spraying (4)Wet covering

2) MEMBRANE CURING:
 In case of membrane curing the surface of
concrete is covered by membrane or a sealing
compound. The idea is to obtain a continuous
impervious film to prevent moisture in the
concrete from escaping by evaporation.
3) CALCIUM CHLORIDE:

 Calcium chloride can be used either as a surface coating or as

an admixture. It is based on the affinity of salt for moisture. The
salt not only absorb moisture from the atmosphere but also aids in
retaining a part of the mixing water.

 It should not be used in hot, aired and semi- aired climate.

Calcium chloride is distributed at the rate of 0.8 to 0.9 kg per m 2
area. The concrete surface is sprinkled with water immediately
before application. The salt is not applied during rain, and if it
rains within two hours of application, the calcium chloride must be
replaced.
 WATER PROBLEMS
 Water problem or water scarcity
Water scarcity is the lack of sufficient available water resources to meet the
demands of water usage within a region. It already affects every continent
and around 2.8 billion people around the world at least one month out of
every year. More than 1.2 billion people lack access to clean drinking water.
Water scarcity involves water stress, water shortage or deficits, and water
crisis.
 Causes
The water sources are contaminated with both bio and chemical pollutants.
21% of the country's diseases are water-related with only 33% of the
country having access to traditional sanitation. Excessive use of
groundwater for agriculture has also caused a strain in the resource. As
India is one of the top agriculture producers in the world, the consumption
of water for land and crops is also one the highest. The results of the
widespread use of ineffective techniques used for irrigation aligned with
mismanagement are few of the reasons for the water deficit. 
 IMPACT ON CITITES
In 2016, the city of Latur experienced a great water shortage. Much of the
farming industry came to a halt and created both food insecurity and massive
unemployment. Much of the local economy and farming regions nearly
collapsed with the citizens having no choice but to use the polluted water.
METHODS FOR REDUCING WATER IN
CONCRETE
1. Overhead heat / heated table
 Another common way to quicken curing is to apply heat from
the outside. Arrange all your molds neatly on a table and either blast
them from above with a space heater or radiant heating lamps, or
install some custom heating mats onto a table specifically used for
casting. This type of custom table is commonly used by furniture
makers and concrete countertop makers who need to accelerate
curing times either for structural reasons or for efficiency reasons.
 If you can increase the ambient temperature of the air around the
molds, and concrete you will quickly begin to accelerate your curing
times. I would not recommend exceeding 150*F in this way. Even
temps of 100* will do a lot to get that concrete to dry faster.
2. Hot or Warm Water in Your Mix
 Water is the catalyst for the reaction that
occurs in your concrete. Cold water will have a
slow curing reaction. Hot water will allow the
curing action to happen much more rapidly.
You can use this to your advantage by using
warm or hot water in your mix.
 For example, if I use HOT tap water in
my mix as opposed to room-temp water, I will
usually see about a 30% decrease in curing
time. Using cold water in your mix could
increase curing times by 30% or more
 3.Using less water / Using a water-reducer
 Simply put, the more water in your mix, the longer it
takes to set. When varying your water content, you never want
to drop below the minimum amount of water required to
saturate the amount of dry mix you have. However, excess
water over this amount will give you more fluidity but it will
also increase your curing times.
 Try reducing the water by a few grams each time you
mix. Reducing too much water will make your concrete thick,
and this may not work for your workflow if you are used to
pouring more fluidly into your moulds.
 Sprinkle some water-reducer into your concrete
immediately after incorporating the water and all the dry mix.
Water-reducer will increase the fluidity of the mix without the
need
• 4. Steam curing
 EXPREIMENTAL SETUP

 Process of casting cube

Production of quality self -curing concrete requires greater carefulness at

every stage of manufacture of concrete. If precise care is not taken, and good
results are not observed, the resultant Self Curing Concrete is going to be of
bad quality. With the same material if intense care is taken to exercise
control at every stage, it will result in good Self Curing Concrete. The
various stages of manufacture of Self Curing Concrete are:
(a) Batching
(b) Mixing
(c) Transporting
(d) Placing
(f) Curing
 
 Batching:
The measurement of materials for making self-
curing concrete is known as batching. There are two
methods of batching:-
(I) Volume batching
(ii) Weight batching
 Mixing:
The aim of mixing of concrete is to produce a
homogenous and uniform colored SCC. This means
that the different constituted material of concrete be
uniformly distributed throughout the concrete mass.
There are two methods adopted for mixing concrete:
(i) Hand mixing (ii) Machine mixing
Casting:
It is not enough that a self-curing concrete
mix correctly designed, batched,
mixed and transported; it is also importance that
the concrete must be placed in
systematic manner to yield optimum results.

 Curing of concrete:
We will be using minimum water as possible
for curing. So after 28 days we have to get
desired strength of cement.
 TEST ON CONCRETE
 Test on fresh concrete
1. Slump test
Slump test is the most commonly used test of measuring
consistency of concrete. It can be employed either in laboratory or
site work. It is used conveniently as a control test and gives an
indication of the uniformity of concrete from batch to batch.
 Test on harden concrete

1. Compressive strength of concrete

The compressive strength test on hardened concrete was performed on a
2000 KN capacity compression testing machine. Compressive strength of
concrete is the most important characteristic of concrete, which is measured by
engineers in designing structures. The compression test measures concrete
strength in the hardened state.
Size of concrete cube specimen is 15 cm x 15 cm x 15 cm are used for
compression test
 CONCLUSION AND REFRENCES
 

 CONCLUSION
 
o Reduce of curing period
o Normally a large amount of water is needed for curing purpose
but performing this experiment reduce water quantity
o Increase in compressive strength of concrete
o The Compressive and tensile power of self-curing Concrete
for 7 and 28 days is discovered out and as compared with
traditional concrete of similar mix design
 REFRENCES
o Concrete technology by r.p rethaliya
o Water supply and sanitary engineering byr.prethaliya
o Wikipedia’s article
o Ijarest journal
o Google search engine
o www.research.net
 FUTURE SCOPE

o Conduct all required tests like slump test, compressive

strength of concrete with different grades of concrete mix of
Self Curing Concrete.
o Casting of different Self Curing Concrete cubes with different
proportions of mix design.
o Compare test results of Self Curing Concrete with
conventional concrete
THANK YOU