Contents Introduction Basic concept & context of Work Objective of Work Literature Review Fly Ash Mix Design Compressive Strength of Concrete Experimental Work Cylinder Select Sample Preparation Used Materials Concreting Curing Laboratory Test Result and Analysis Conclusion

1. COMPARATIVE STUDY ON COMPRESSIVE
STRENGTH OF FLY ASH CONCRETE
Experiment on Compressive Strength of Concrete by Partial Replacement of Cement with Fly ash.
Members:
Md. Nasir Bin Arefin (150220002), Md. Afsar Ali (150220003),
Atanu Kumar Dhar (150220004), Sazib Halder (150220016), Md.Roni Miah (150220035)

2. ➢Introduction
▪Basic concept & context of Work
▪Objective of Work
➢Literature Review
▪Fly Ash
▪Mix Design
▪Compressive Strength of Concrete
➢Experimental Work
▪Cylinder Select
▪Sample Preparation
▪Used Materials
▪Concreting
▪Curing
▪Laboratory Test
➢Result and Analysis
➢Conclusion
Contents

3. Introduction

4. Basic concept & context of Work
1.Presently in Bangladesh, it is estimated that 1.3 million cubic feet
of fly ash is produced per annum for dumping from thermal
power plants alone, and is estimated to reach an alarming
crescendo of 9.5 million cubic feet by 2018. The environmental
degradation due
to dumping of fly ash aggravates the situation
2. The advantages of using fly ash far outweigh the disadvantages.
The most important benefit is reduced permeability to water and
aggressive chemicals. Properly cured concrete made with fly ash
creates a denser product because the size of the pores are reduced.
This increases strength and reduces permeability.
Now a days fly ash is widely used as replacement of cement which can
reduce the amount of fly ash and in that way the pollution of
environment with the great advantages in infrastructure sector.

5. ❖ To study of the impact of fly ash in environment.
❖ To evaluate of the importance of fly ash in concrete , ultimately in the sector of
infrastructure.
❖ To test the compressive strength of concrete where fly ash is using as
replacement of cement.
❖ To analysis the numerical value of load and compare the strength of concrete.
❖ To spread out and increasing the use of fly ash widely.
Objective of Work

6. Literature Review

7. Fly Ash:
Fly ash is one of the common residues produced from combustion of coal. In past, fly ash was unconditionally
released into the atmosphere. Recent concerns about environmental pollution led to prohibition of its atmospheric
release and mandated the use of various mechanisms to trap it before release. Subsequently, the storage and
recycling of this huge quantity of fly ash has become a new concern.
Fly ash is broadly classified into two categories, Class C fly ash and Class F fly ash. The main difference between
these two classes lies in their calcium content. While Class C fly ash generally contains more than 20% lime, Class
F contains less than 20%. The ash analysis of Fly ash ( Class F ) obtained from Barapukuria Power

8. Property ASTM C618 Requirements, %
SiO2 plus Al2O3 plus Fe2O3, min 70
SO3, max 5
Moisture content, max 3
Loss on Ignition, max 6
Class F fly ash Chemical Composition

9. Mix Design:
Concrete mix design is the process of finding the proportions of concrete mix in terms of ratios of cement,
sand and coarse aggregates. M10 M15 M20 etc. are all grades of concrete. It is designation of grades of concrete
mix. Letter M refers to the mix and number to specified characteristic compressive strength of 15 cm cube at 28
days expressed in N/square mm. we have selected M15 grade which ratio is 1:2:4 whereas if we take 1 part of
cement then 2 part of fine aggregate (sand), and 4 part of coarse aggregate (brick chips).

10. Compressive Strength of Concrete:
Compressive strength is the capacity of material or structure to resist or withstand under
compression. The Compressive strength of a material is determined by the ability of the
material to resist failure in the form cracks and fissure.
In this test, the push force applied on the both faces of concrete specimen and the maximum
compression that concrete bears without failure is noted.

11. The compressive strength of concrete tested by the
machine which name is UTM
(Universal Testing Machine)
As we all know that concrete
is a mixture of sand, cement, and
aggregate The strength of the
concrete depends upon many
factors like individual compressive
strength of its constituents (Cement,
Sand, aggregate), quality of
materials used, air entrainment mix
proportions, water-cement ratio,
curing methods and temperature
effects.
Figure: Universal Testing Machine

12. Experimental Work:
Cylinder Select: Usually Compressive Strength results are used to ensure that the
concrete mixtures as delivered meet the desire requirement. Strength test results used
for quality control, acceptance of concrete and estimating the strength of structure.
Cylindrical specimens are tested in accordance with ASTM39. Standard sizes of tests
specimens are 4×8 in. (100×200mm) or 6×12 in. (150×300mm) concrete cylinder. The
smaller specimens tend to be easier to make and handle in the field and the laboratory.
We have taken 4×8in. of size of cylinder.
Fig: 4in× 8in of size of cylinder.

13. Sample Preparation:
In this experimental study, a total of 8 numbers of concrete specimens were casted. The specified size of
Cylinder 200mm×100mm.The mix design of concrete was done according to M15 grades. Depending on the
quantities of ingredients in the mixes, the quantities of Fly ash of 10%,25% and 45% replacement by weight were
estimated and Cylinder were casted.The specimens were taken out of the curing tank just prior to the test. The
compressive test was performed using a Compression testing machine (UTM).
Number of
specimen
Fly Ash
(kg)
Cement
(kg)
Fine Aggregate (kg) Coarse Aggregate
(kg)
2 00 1.96 3.92 7.84
2 .196 1.764 3.92 7.84
2 .490 1.470 3.92 7.84
2 .882 1.078 3.92 7.84

14. Concreting :
➢ Mild Steel Cylinder mold was used for casting. Forms must be tight, rigid, and strong. If the forms are not tight
there will be excessive leakage at the time the concrete is placed.
➢ Concrete mixture was made using a 1:2:4 ratio of cement to sand to aggregate by volume
➢ A w/c ratio of 0.45 was used here. w/c ratio determines the strength, durability and workability of the concrete.
Fig:Adding Fly ash
Fig: mixing all materials

15. Concreting:
Fig: Mixed Concrete Fig: Mixing Materials

16. Fig: compacting with for reduce void
Concreting:

17. Curing:
Curing is the process of controlling the rate and extent of moisture loss from concrete during cement hydration
In order to strengthen concrete structure we kept the concrete cylinder for 28 days.
FIg: Curing procedure

18. Laboratory test:
After curing the test of cured cylinder is needed to identify the compressive strength of concrete. Laboratory
experiments includes experimental setup of structural models and UTM (Universal Testing Machine), tests and
data collection. The experiments were conducted in UTM in the Department of CE at European University Of
Bangladesh. The laboratory setup was developed with UTM and other machine and equipment of civil engineering.
Fig: UTM
Fig: Compressive Test process is going on UTM

19. Result and analysis:
Each set of 2 cylinder of M15 grade of concrete were tested in Compression Testing
Machine with 0%, 10%, 25% and 45% replacement of cement with fly ash to determine the
compressive strength after 28 days of curing. Average value of these 2 readings gives the
average compressive strength of concrete. The average compressive strength of cylinders at
the age of 28 days were found as 18.56N/mm² for normal concrete with no fly ash and it
reduced to 16.90N/mm² when 25 % of cement was replaced with fly ash. The decrease in
compressive strength of concrete after 28 days of curing was found to be 8.94%, when 25%
of cement was replaced with fly ash.

20. Mix Load (KN) Average Compressive
Strength (N/mm2)
0% of Fly ash 417.63 18.56
10% of Fly ash 402.09 17.87
25% of Fly ash 380.47 16.90
45% of Fly ash 360.29 16.01

21. Conclusion:
From the experimental work carried out for M15 grade of concrete by partial replacement of cement with
10%, 25% and 45% of fly ash, the following conclusions were drawn.
The compressive strength of concrete decreases with increase in fly ash content. The reduction in
compressive strength of concrete at the age of 28 days was found to be 3.71%, 8.94% and 13.73% for 10%,
25% and 45% replacement of cement with fly ash.
Fig: Set of cylinder in
UTM
Fig: Failure going for Extra load.

22. Future Recommend:
1.By providing fly ash a replacement of cement to
concrete strength improved significantly.For availability
and economical saving it can be use widely.
2. Use of fly ash should not be exceed over 25% and
not minimum rate is 10%.

23. Thank You For Your
Concern…!!!
Any Question?