STRENGTH AND DEFORMATION CHARACTERISTICS
OF REINFORCED BOTTOM ASH
A Thesis Submitted in Partial Fulfillment of the Requirements
For the Degree of
MASTER OF TECHNOLOGY
in
CIVIL ENGINEERING
(GEOTECHNICAL ENGINEERING)
by
YOGESH KUMAR SHARMA
(ROLL NUMBER: 17062056)
Under the Supervision of Dr. Supriya mohanty (Supervisor)
Department of Civil Engineering
Indian Institute of Technology (Banaras Hindu University)
Varanasi – 221005
July 2018
Department of Civil Engineering
Indian Institute of Technology (BHU)
Varanasi – 221005 (India)
CERTIFICATE
This is to certify that the thesis entitled, “Strength and Deformation Characteristics of
Reinforced Bottom Ash” submitted by yogesh kumar sharma in partial fulfillment of the
requirement for the award of Master of Technology Degree in Civil Engineering with
specialization in Geotechnical Engineering at the Indian Institute of Technology (BHU),
Varanasi is an authentic work carried out by him under our supervision and guidance.
To the best of our knowledge, the matter embodied in the thesis has not been submitted to any
other University/Institute for award of any Degree.
Dr. Supriya Mohanty
Assistant Professor
Professor Prabhat kumar singh
Head of the Department
Department of Civil Engineering
Department of Civil Engineering
Indian Institute of Technology (BHU)
Indian Institute of Technology (BHU)
Varanasi – 221005
India
Varanasi – 221005
India
DECLARATION BY THE CANDIDATE
I hereby certify that the work embodied in thesis is my own bona fide work and carried out by
me under the supervision of Dr. SUPRIYA MOHANTY from 2018 to 2019, at the Department
of Civil Engineering, Indian Institute of Technology (BHU), Varanasi. The matter presented in
the thesis has not been submitted for the award of any other degree/diploma. I declare that I have
faithfully acknowledged and given credits to the research workers wherever their works have
been cited in my work in this thesis. I further declare that I have not willfully copied any other’s
work, paragraphs, text, data, and results etc., reported in journals, books, magazines, reports
dissertations, and theses etc., or available at websites and have not included them in this thesis
and have not cited as my own work.
Date:
Place: Varanasi
Yogesh Kumar Sharma
CERTIFICATE BY THE SUPERVISORS
It is certified that the above statement made by student is correct to the best of our knowledge.
Dr. Supriya Mohanty
Assistant Professor
Department of Civil Engineering
Professor Prabhat kumar singh
Head of the Department
Department of Civil Engineering
Indian Institute of Technology (BHU)
Indian Institute of Technology (BHU)
Varanasi – 221005 (India)
Varanasi – 221005 (India)
COPYRIGHT TRANSFER CERTIFICATE
Title of the Thesis: STRENGTH AND DEFORMATION CHARACTERISTICS OF
REINFORCED BOTTOM ASH
Name of Student: YOGESH KUMAR SHARMA
Copyright Transfer
The undersigned hereby assigns to the Indian Institute of Technology (Banaras Hindu
University), Varanasi all rights under copyright that may exist in and for the above thesis
submitted for the award of the M.Tech in Civil Engineering (Geotechnical Engineering).
Date:
Place: Varanasi
YOGESH KUMAR SHARMA
Note: However, the author may reproduce or authorize others to reproduce material extracted
verbatim from the thesis or derivative of the thesis for author’s personal use provided that the
source and the institute’s copyright notice are indicated.
DEDICATED TO ALMIGHTY
ACKNOWLEDGEMENTS
I feel great pleasure in expressing my deep sense of gratitude to Dr. Supriya Mohanty,
Assistant Professor, Department of Civil Engineering, IIT (BHU) Varanasi for his invaluable
guidance, and suggestion regarding preparation of this dissertation. I am grateful to have her as a
mentor during this work and for her keen interest in the progress of the work despite her preoccupation with other responsibilities.
I would also like to thanks to the Head of the Civil Engineering Department Prof. Prabhat
kumar singh, Prof. P. K. Basudhar (Visiting Faculty), Prof. Arun Prasad, Dr. P. Bala
Ramudu, Mr. Suresh Kumar, Dr. Manash Chakraborty and other faculty members of
Department of Civil Engineering, IIT (BHU) Varanasi for their advices, assistance and
encouragement during this work.
I greatly appreciate the cooperation extended to me by staff members of geotechnical
engineering laboratory especially Mr. Basanta Prasad, pal ji, Deepak ji and others for their
assistance during my experimental work. I express my sincere regards to my friends and to all of
them who provided me direct or indirect assistance in completion of this work.
Finally I would like to comment that i am highly indebted to my family for their trust and
support during my tough times over the years.
Date:
Place: Varanasi
Yogesh Kumar Sharma
Roll No. - 17062056
M. Tech (Geotechnical Engineering)
IIT (BHU), Varanasi
ABSTRACT
According to the World Bank data, 39.20% of the total electricity production in world in year
2015 was from coal based sources (World Bank report 2015) while in 1978, the contribution of
coal constituted nearly 30.57%. This has led to rapid increase in generation of enormous quantity
of ash products. Waste Disposal of such a huge quantity of coal ash is costly and create
environmental hazard especially in urban areas. In India, the overall utilization of fly ash in
different sectors in year 2018 was approximately 60%, which means still huge amount has
unutilized. Therefore a productive utilization of ash material will not only offer a sustainable
solution by reducing potential solid waste disposal problems but also overcome the scarcity of
natural high quality granular material and provide an economical alternative geotechnical
material which will encourage economic benefits to both electricity producers and construction
agencies.
The practice of use of reinforcement in granular soils is quite popular as it has led to significant
improvement in response of soil against its use in retaining structures, foundations, embankments
and pavements. Reinforced earth is a composite material which is formed by the association of
frictional soil and tension resisting reinforcement elements. Provided reinforcement suppresses
the normal tensile strains in the soil mass through frictional and interlocking mechanism. There
are several experimental studies available on shear strength of reinforced soil in the literature,
however very scarce is available on reinforced bottom ash. Reinforcement of bottom ash results
in a composite material which can be used as an alternative construction material in the field of
geotechnical engineering in various applications such as retaining structures, construction
backfill, subbase material for pavements and foundation base material. In present study first the
physical, chemical and geotechnical properties of source material bottom ash were assessed and
then strength and deformation behavior of reinforced bottom ash has been analyzed.
Conventional triaxial compression tests under undrained conditions on samples of dry bottom
ash reinforced with geotextile and geogrid have been conducted through varying test parameters
like number of reinforcement layers, confining pressure, type of reinforcement and imposed
strain level. Dry samples are preferred due to some difficulties related to testing saturated
specimens. Effect of reinforcement on stress-strain behavior, shear strength parameters,
deformation behavior, Strength ratio, and failure pattern was studied. Test results are analyzed
and bottom ash had shown very much advantageous properties from geotechnical engineering
points of view which are comparable to natural conventional granular sands. The results obtained
from the study may not be truly representative of in situ performance but are expected to provide
useful and comparative information for understanding the behavior and mechanism of reinforced
bottom ash. Conclusions of this study can help in implementation of utilization of industrial
waste resource material bottom ash in various fields with improved engineering properties.
Keywords: Bottom ash, Index of Crushing, Geosynthetics, strength ratio, Influence Spacing.
CONTENTS
Page No.
CHAPTER 1
INTRODUCTION
1.1
Ash Material
1
1.2
Reinforced Soil
4
1.2.1 Basic Mechanism of Reinforced Soil
6
1.3
Objective of the Present Study
8
1.4
Scope of Work
9
1.5
Report Outline
10
CHAPTER 2
LITERATURE REVIEW
2.1
Introduction
11
2.2
Literature Studies on Coal Ashes
11
2.3
Literature Studies on Reinforced Soil
17
CHAPTER 3
DEVLOPMENT OF TEST PROGRAM
3.1
General
25
3.2
Materials Used
25
3.2.1 Bottom Ash
25
3.2.2 Reinforcement Used
25
Experimental Program for Material Used
25
3.3.1 Bottom Ash
25
3.3
3.3.1.1 Geotechnical Characteristics
26
3.3.1.1.1 Grain Size Analysis
26
3.3.1.1.2 Relative Density
27
3.3.1.1.3 Specific Gravity
27
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3.3.1.1.4 Compaction Characteristics
27
3.3.1.1.5 Permeability
27
3.3.1.1.6 Direct Shear Test
28
3.3.1.1.7 Triaxial Test
28
3.3.1.2 Chemical Characteristics
3.3.1.2.1 Scanning Electron Microscopy (SEM)
28
3.3.1.2.2 X- Ray Diffraction (XRD)
29
3.3.1.2.3 Energy Dispersive X-Ray (EDX)
29
3.3.2 Reinforcement Material
3.3.2.1 Mechanical Properties
29
29
3.3.2.1.1 Wide Width Tensile Strength Test
29
3.3.2.1.2 CBR Puncture Test
32
3.3.3 Development of Test Program on Composite Material
3.3.3.1 Triaxial Compression Tests
CHAPTER 4
28
33
33
REESULTS AMD DISCUSSIONS
4.1
General
37
4.2
Geotechnical Characteristics of Bottom Ash
37
4.3
Chemical Characteristics
43
4.4
Reinforcement Material
46
4.5
Triaxial Compression Test Results
47
4.5.1 Effect of Reinforcement on Stress-Strain Behavior
56
4.5.2 Strength Ratio and Strength Difference
69
4.5.3 Effect of Confining Pressure on Strength of Bottom Ash
79
4.5.4 Failure Pattern
82
Page | ii
CHAPTER 5
CONCLUSIONS
5.1
Epilogue
87
5.2
Conclusions
87
5.2
Contribution of Present Study to the Existing Studies and
91
Practical Applications
5.3
Limitations of the Present Study
91
5.4
Suggestions for Future Study
92
REFERENCES
93
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