This laboratory report examines the properties of admixtures (super plasticizers) used in concrete, including solid content, rheological properties, and chloride content. Various tests were performed on the admixtures to determine these properties, such as marsh cone tests to evaluate rheological properties, ash content tests to determine solid content, and chloride content tests. The report summarizes the results of these tests, such as an average ash content of 4.95% and a chloride content of 0.0237% for the specific admixture tested. Compressive strength tests on concrete cubes yielded an average compressive strength of 205.2 kg/cm2.

1. Department of Civil Engineering
Laboratory report Cover
Plasticizers (solid content, expose chloride, etc.)
(CVP771)
Construction Technology laboratory
Submitted by: HAFIZULLAH SADAT Date Submitted: Jan.23, 2018
Instructor: PRO.SHASHANK BISHNOI

2. Executive Summary
This report examines the different things in admixtures (super plasticizers) such as solid
content, rheological properties and chloride content. Different test were conducted to
determine the above properties.
The tests were done in a controlled environment under the supervision of a lab instructor
and lab assistants.
For rheological properties of admixture marsh cone test was conducted and indicated
that the % of dosage of same plasticizer for same type of cement having same
w/c ratios different, ash content teat was done and shown that there was
4.95% ash in that specific admixture, and finally chloride content test was
performed and shows the result of 0.0237% chloride in admixture.

3. Introduction
Plasticizers are the organic or combination of organic and inorganic substances which
reduces water content for certain degree of workability, when added in mix. The basic
products consisting plasticizers are anionic surfactants (such as lignosulphonates, salts
of sulphonates hydrocarbon) nonionic surfactants (such as polyglycol esters,
hydroxylated carboxylic acid products) and others such as carbohydrates, etc. among
them calcium, sodium and ammonium lignosulphonates are commonly used. Plasticizers
are mixed from 0.1% to 0.4% by weight of cement used and it reduces 5% to 15% of
water with the increment of workability from 3 to 8cm slump. In the mix, the cement grains
absorbs the plasticizers molecules and results change in the surface charge of the same
sign which causes repulsive forces and makes the dispersion which increases plasticity
and workability. Some Plasticizer also entrails the air but a good plasticizer is that which
entrains air less than 2% only. The plasticizers are available in market in various brands
with specifications for composition, dosages etc.
Here are some of the tests which were conducted on plasticizers for; defining the quantity
of plasticizers or for evaluation of the optimum plasticizers dosage through Marshal Cone
test, determination of solid content and chloride exposition.

4. Marsh Cone Test
Test objectives
Marsh cone test is reliable and simple method to study the rheological properties of
cements and mortars, flow time of cement/mortar through marsh cone is indicator of
viscosity, which depends upon cement plasticizer compatibility.
It is widely used to study cement plasticizer compatibility and to determine optimum
plasticizer dosage of a specific cement- plasticizer combination.
Apparatus
The following apparatus are used in Mash Cone test:
 It’s consist of a conical brass vessel held on a wooden stand with an
orifice of 8mm at its bottom.
 A stop watch is needed to measure the time taken by 1 liter of cement
or mortar to pass through the vessel.
 A mortar mixer is also needed to prepare the cement paste with

5. Procedure
Material used;
Cement = 2 kg
Water = 600 gr
Super plasticizers = 0.2%- 0.6% (weight of cement)
W/c = 0.3
Cement paste is prepared in mortar mixer using 2 kg of cement and w/c ratio
of 0.3 .In this test Water/cement ratio 0.3 was considered. Water is added in
two steps- 70% of water is added in beginning of mixing and rest 30% of
water is mixed with super plasticizer, and added afterwards. Cement slurry is
prepared with the w/c ratio of 0.30 and admixture dosage of 0.2 %. Cement
slurry is made to flow through marsh cone, a glass biker is placed bellow the
cone and paste is allowed to flow freely through marsh cone into the glass
biker and time in seconds is measured until the past quantity is reached to
100mm, using a stopwatch. The procedure is repeated gradually increasing
the S.P. Dosage in steps of 0.2%. Similar tests are conducted for rest of super
plasticizers.
Observation table
No. Type of
cement
W/C
ratio
Qty of
Cement
Dosage of S.P
in
%
Qty
Of S.P
Marsh
time
1 OPC 0.3 2kg 0.2% 4gr Infinite
2 OPC 0.3 2kg 0.4% 8gr 27.26sec
3 OPC 0.3 2kg 0.5% 10gr 20.71sec
4 OPC 0.3 2kg 0.6% 12gr 20.17sec

6. Result
The optimum dosage of SPR Super plasticizer for OPC cement is between
0.425 to 0.45%. Different results have been recorded in above table.
Conclusion
As shown in previous table different values of time have been recorded for
different quantity of super plasticizer, it is indicated that the % of dosage
Of same plasticizer for same type of cement having same w/c ratios different.
Ash Content in S.plasticizers
Test objectives
The ash content gives an indication of organic constituents, is determined by
igniting the admixture at 600 Celsius to remove any organic material from the
Apparatus
Steel crucible
Scale

7. Procedure
For determination of solid content, particularly ash content at super
plasticizers the following procedure were conducted, this test was done for
two crucible separately.
In first sample 10gr of super plasticizer were placed in crucible, then place the
crucible over an air oven to at 90 C to remove the liquid part by evaporation.
Then transfer the crucible with solid contents to a muffle furnace and heat
them till temperature reach up to 300 Celsius during 1 hour, and continue till
get it up to 600 Celsius. Remain this sample for a while, about 1 h or more,
after that removed the crucible from furnace and leave it till it getting cold,
the same procedure was done for second crucible also,10gr of super
plasticizers were placed in crucible. After that, weight the crucible in two
steps: weighting the crucible plus lid and content and weighting the crucible
with lid and sample, the following is the calculation part of this test which we
have done during testing.

8. Calculation
This part is included three steps:
W1: the weight of crucible and lid (scale it before placing plasticizer into
crucible.
W2: this weight include crucible, lid and sample (after placing the plasticizer
in crucible)
W3: this is include the weight of crucible, lid and ash (after removing the
crucible from furnace)
Ash content in super plasticizer =
𝑊3−𝑊1
𝑊2−𝑊1
x100
Sample 1:
W1 = 25.99 gr
W2 = 36 gr
W3 = 26.53 gr
Ash content in super plasticizer (sample 1) =
26.53−25.99
36−25.99
𝑥100 = 5.39%
Sample 2:
W1 = 25.97 gr
W2 = 35.97 gr
W3 = 26.43 gr
Ash content in super plasticizer (sample 2) =
26.43−25.97
35.97−25.97
𝑥100 = 4.6%
Ash content in super plasticizer (Avg of samples) =
5.39+4.6
2
=4.95%
Conclusion
As two sample were taken, different no. of W were recorded for super
plasticizers. Ash content of super plasticizer was determined by formula, and
two results were recorded, as a result average of two result were taken and
final result was 4.95% of ash content in super plasticizers.

9. Chloride Content of S.Plasticizers
Test objectives
This test objective are to determine chloride content of chemical admixtures
which are needed to assist mix design in concretes that require a limited
chloride content. Chloride results can exhibit if an admixture does not contain
chlorides. Some admixtures have calcium chloride, the results can be used to
provide quality control of chloride content.
Apparatus
 Beaker
 Scale
 Magnetic stirrer

10. Procedure
For chloride determination, 3 gr of super plasticizer and 100gr of water were
mixed and placed in a beaker, then the beaker was transferred to magnetic
stirrer which had about 700 rpm speed for better mixing, and to gain
uniformity and homogeneity and stir until dissolution is complete. Mix
temperature was 100 Celsius. After that the mix was transferred to chloride
indicator machine to determine chloride percentage.
Conclusion
Chloride (Cl-), determined by potentiometric titration reported as weight
percentage of the sample.
Test result was recorded from chloride indicator machine, which was 0.0237%
the chloride content in that solution.

11. Compressive Strength Test of Concrete Cubes
Test objectives
An idea about all the characteristics of concrete. By this single test one judge
that whether Concreting has been done properly or not.
Compressive strength of concrete depends on many factors such as water-
cement ratio, cement strength, quality of concrete material, and quality
control during production of concrete etc.
Test for compressive strength is carried out either on cube or cylinder.
Apparatus
Steel cubes
Compression testing machine
Procedure
Prepare concrete mix for compressive test, after that place concrete in 150
mm Cube Moulds, and place the cubes for 24 hour in water after curing time
transfer the cubes to compressive machine for testing.

12. Conclusion
The following observations were recorded from compressive test of cubes:
Details Samples
Specimen 1 Specimen 2 Specimen3
Compressive
load (ton)
45.5 48 45
Compressive
strength
(kg/cm2
)
(45.5x1000)/225
=202.22
(48x1000)/225
=213.33
(45x1000)/225
=200
Average
compressive
strength
(kg/cm2
)
[202.22+213.33+200]/3 =205.2 kg/cm2
The average strength of concrete samples was 205.2 kg/cm2