A FINAL YEAR PROJECT REPORT PRESENTED BY:

NSENGIMANA Innocent 216144701

KUBWIMANA Delphine 216189357

TWAMBAJIMANA Adeline 216280184

Under the Guidance of: Dr. ABAHO G. Gershome

July 2019

COLLEGE OF SCIENCE AND TECHNOLOGY

SCHOOL OF ENGINEERINGDepartment of CEGE

“AN EXPERIMENTAL STUDY ON USE OF COW DUNG ASH AND RICE

HUSK ASH AS PARTIAL REPLACEMENT OF CEMENT IN CONCRETE”

OutlinesIntroduction

Objectives

Conclusions

References

Recommendations

Problem Statement

Literature Review

Methodology

Data collections

Data interpretations

Introduction

• The consumption of cement in concrete industries has been increasing day by day to fulfil

the needs of infrastructure due to growing population, industrialization and urbanization.

• The cement production in manufacturing industries leads to the negative effects to

the environment due to emitting of polluted gases like carbon dioxide (CO2) that

leads to the air pollution which has more effects on the climate change and global

warming.

• Supplementary binding materials such as cow dung ash, sawdust, fly ash, silica, rice husk

ash enable concrete technology to use millions of tons of byproducts materials that would

be waste disposal problems.

Problem Statement

• The population in developing countries like Rwanda are highly increasing day by day.

• They need infrastructures facilities such as buildings, highways, hydraulic structures,

airports, parking to accommodate them effectively.

• The cost of building materials especially plastering and cementitious materials in

Rwanda is very high.

• Environmentally, cement manufacturing industries produces fumes which lead to the air

pollutions.

• Additionally, large amount of agricultural wastes produced in agri-processing

industries like rice husk has been causing waste disposal problems.

Objectives • Main objective: The main objective of this work is an experimental study on

use of cow dung ash and rice husk ash as partial replacement of cement in

concrete.

• Specific objectives

• To examine the effectiveness of using CDA and RHA as partial replacement of

cement by studying strength parameters.

• To investigate the compressive strength and of concrete with CDA and RHA to

that of normal concrete.

• To use supplementary cementitious materials to produce concrete which is

affordable and structural light in weight.

Literature Review

• (MINAGRI, 2012) reported that Rwanda produces 81,908 metric tons of short grain rice a

year.

• Rice husk is agricultural waste which account for the 649.7 million tons of rice

produced worldwide annually (Habeeb & Mahmud, 2010)

• (Dabai & Muhammad, 2009) studied the effect of RHA as cement admixture by

testing the compressive strength of cement cubes produced by replacing cement

percentages with the RHA.

• (Pavithra, 2016) reported that dry cow dung is utilized as fuel energy for domestic

intention, which generates solid waste ash and observed that cow dung ash in cement

concrete is durable as compared to the normal concrete strength.

• (Kumar & Reddy, 2015) searched on cement replacement in concrete by CDA

and found that 5% of CDA replacement increases the compressive strength. It

observed that the 5% of CDA replace cement in mortar.

• The three constituents of hydraulic cement ae lime, silica and alumina. In addition,

other small oxides are added (Duggal, 2008)

• Aggregates make up about 75% of the volume of concrete, so their

properties have a large influence on other properties of the concrete ( Alexander

& Mindess, 2005)

• (SHETTY, 2005) discussed that RHA is obtained by burning rice husk in

controlled temperature with aim of protecting environmental pollution.

Methodology

Some taken Photos

Sieve Analysis

Cube weighing

CDA and RHA Consistency test Curing tank

Compressive testing machine

Data recording

Results Analysis and interpretations

0.29

0.33

0.36

0.41

0.43

0.25

0.27

0.29

0.31

0.33

0.35

0.37

0.39

0.41

0.43

0.45

0 5 10 15 20

Con

sist

ency

lim

it

RHA+CDA%

CONSISTENCY LIMIT

Consistency limt curve

This test is carried out to determine the

standard water required to produce workable

paste of cement .

The RHA and CDA are mixed with cement to

produce paste as a percentage of weight of

cement.

The test result show that the much water is

required to obtain the desired consistency as

the percentage of CDA and RHA increase.

Interpretations

Results Analysis and interpretations Cont’d

45

49

56

68

75

0

10

20

30

40

50

60

70

80

0 5 10 15 20

Slu

mp

RHA+CDA%

Slump Result

Workability implies the ease to

work with which concrete mix is

handled.

the figure shows the workability

of each mix of concrete varying

the % of RHA+CDA with the

highest workability value of 75mm

is obtained for 20% of RHA+CDA

Results Analysis and interpretations Cont’d

24

51

.83

23

69

.7

23

79

.8

23

46

.7

24

52

.73

23

71

.13

23

82

23

49

.07

24

52

.53

23

70

.8

23

80

23

48

.5

2300

2310

2320

2330

2340

2350

2360

2370

2380

2390

2400

2410

2420

2430

2440

2450

2460

0 5 10 15

Con

cret

e D

ensi

ty k

g/m

3

RHA+CDA %

Density of Concrete Results

7Days 14days 28days The Density of the cubes decreases as the

percentage content of CDA+RHA increases.

The lightness in weight of specimen is due to

the presence of CDA+RHA and the

higher the percentage of CDA+RHA the

lighter the specimen.

Also, the result reveals that the

Density of specimen increases with age. The

barchart represents that the highest densities

obtained on 14 curing days.

Interpretations

Results Analysis and interpretations Cont’d

37.75

31.25 31.25

25.25

0

5

10

15

20

25

30

35

40

0% 5% 10% 15%

Co

mp

ress

ive

Str

eng

th o

n 2

8 c

uri

ng

da

ys

RHA+CDA

Compressive strength of concrete

The bar chart shows the pattern of the Cube

Strength with different percentages of CDA+RHA

against curing time, the Cube Strength is highest

at 28 days with 37.75N/mm2 at 0% while the

lowest Cube Strength is recorded at 28 days with

25.25 N/mm2 at 15%. The compressive strength

of concrete deceases with increases percentages

of CDA+RHA.

The compressive strength of concrete remains

constant on replacement of 5% and 10%.

Conclusion and Recommendations

• Cow Dung Ash and Rice Husk Ash concrete can be made to perform well in certain floor and wall

applications when a ten percentage (10%) replacement is not exceeded.

• The Cow Dung Ash and Rice Husk Ash requires more quantity of water as the percentage increases in the

concrete, therefore it has a serious limitation that must be understood before it is put to use.

• The Cow Dung Ash and Rice Husk Ash have an advantage that offers lightness of weight that makes it useful

construction material.

• More water is required to achieve the standard consistency as the amount of CDA+RHA increases.

• Compressive strength decreases as the CDA+RHA content increases and increases as the curing period is

prolonged.

• With strength as a criterion, CDA+RHA of no more than 15% can be used to produce good and quality mortar

and concrete.

Thank You All for you Kind Attention!!!