BEHAVIOUR OF RECYCLED CONCRETE IN M30 AND M35 GRADES

WITH NANOSILICA
A dissertation submitted in partial fulfillment of the requirements for the award of the degree of

MASTER OF TECHNOLOGY
IN
CIVIL ENGINEERING

With specialization in
STRUCTURAL ENGINEERING
Submitted by

AVINASH PANIGRAHI
Regd. No. 313506301004

Under the esteemed guidance of

Prof. D.S.R MURTY, PhD
Professor of Civil Engineering

DEPARTMENT OF CIVIL ENGINEERING

ANDHRA UNIVERSITY COLLEGE
OF ENGINEERING (A)
VISAKHAPATNAM - 530003
(2017-2019)

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 DEPARTMENT OF CIVIL ENGINEERING

ANDHRA UNIVERSITY COLLEGE OF ENGINEERING (A)

VISAKHAPATNAM

CERTIFICATE
This is to certify that the dissertation entitled “BEHAVIOUR OF RECYCLED CONCRETE
IN M30 AND M35 GRADES WITH NANOSILICA” submitted by AVINASH PANIGRAHI
with Regd. No. 313506301004 of 2017- 2019 batch in partial fulfillment of the requirement for
the award of the degree of MASTER OF TECHNOLOGY in CIVIL ENGINEERING with
specialization in STRUCTURAL ENGINEERING , Andhra University College of
Engineering(A), Visakhapatnam is a record of bonafide research work carried out by him
under my guidance and supervision.

Place: Visakhapatnam Prof. D.S.R.MURTY

Date: (Dissertation Guide)

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 DEPARTMENT OF CIVIL ENGINEERING

ANDHRA UNIVERSITYCOLLEGE OF ENGINEERING (A)

VISAKHAPATNAM - 530003

DISSERTATION EVALUATION REPORT

This dissertation entitled “BEHAVIOUR OF RECYCLED CONCRETE IN M30 AND M35
GRADES WITH NANOSILICA” has been submitted by Mr. AVINASH PANIGRAHI with
Register No - 313506301004 of 2017-2019 batch in partial fulfillment of the requirements for
the award of the degree of MASTER OF TECHNOLOGY in CIVIL ENGINEERING with
specialization in STRUCTURAL ENGINEERING .

EXAMINERS:

1. ___________________ Dissertation Guide

Prof. D.S.R.Murty

2. ___________________ External Examiner

3. ___________________ Chairman, Board of studies

Prof. K. Rambabu (Dept. of Civil Engineering)

4. ___________________ Head of the Department

Prof. T.V. Praveen (Dept. of Civil Engineering)

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 ACKNOWLEDGEMENTS

First I would like to thank God for being with me all the way from the beginning to the
end of this project thesis. I am highly indebted to my dissertation guide Prof. D.S.R.Murty,
Department of Civil Engineering, Andhra University College of Engineering (A),
Visakhapatnam, for his precious time explaining to me including guidance and his valuable
suggestions for completion of my dissertation.

I am also grateful to the help and support I got from my scholar ICCR (Indian Cultural Council for
Relation) all the way from the beginning of the class to the writing of the project.

It is also my wish to express my gratitude and appreciations to Prof.T.V.Praveen, Head of Civil

Engineering Department, Andhra University college of Engineering (A), Visakhapatnam, for providing the
necessary facilities in the department throughout our course of study.

I gratefully express my sincere thanks to Prof. D.S.R.Murty, Chairman, Board of

studies, Civil Engineering Department, Andhra University College of engineering(A),
Visakhapatnam, for his help during the period of work.

Last but not least I would like to thank to the staff members of S.M Laboratory for their
kind help and co-operation during my work.

EPHREM DANIEL HAILU

(318206307018)

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 ABSTRACT
The use of recycled concrete aggregate (RCA) in concrete as partial and full
replacements of natural coarse aggregate is growing interest in the construction industry, as
it reduces the demand for virgin aggregate. In addition, the use of RCA leads to a possible
solution to the environmental problem caused by concrete waste and reduces the negative
environmental impact of the aggregate extraction from natural resources. This paper
presents a comprehensive review on the use of RCA in concrete based on the experimental
data. The most important physical, mechanical, and chemical properties of RCA are
discussed in this paper. However, more emphasis has been given to discuss the effects of
RCA on the fresh and hardened properties and durability of concrete.

This project, however, shows that the recycled aggregates that are obtained from concrete
specimen make good quality concrete. Concrete waste from demolished cubes has been
collected and coarse aggregate of 20% natural and 60% recycled aggregate is used for
preparing fresh concrete of M35. In this study, for the 28th day cube compressive strength
using PPC; the strength for 60% RCA mixes were 16%, 21.% 75%, and 100% results, FOR
3 days, 7days and 28 days respectively.

In this work mechanical properties of recycled coarse aggregate were studied and
Nanosilica is used as partial replacement to Portland pozzolana cement by 1.5% of total
cement weight and M-Sand as a fine aggregate. Strength studies such as compression
strength, split tensile strength and flexural strength were conducted on M35 grades of
concrete with 60% RAC. Durability studies such as permeability test and acid attack on
concrete cubes. To study the microstructure of the concrete XRD analysis and SEM
analysis were conducted. This paper also identifies the gaps existing in the present state of
knowledge on RCA and RCA concrete and provides some recommendations for future
research.

Key words: Recycled aggregate concrete, M-Sand, Nanosilica, SEM, XRD,

Acid exposure, Permeability

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 CONTENTS

DESCRIPTION PAGE NO.

TITLE SHEET I
CERTIFICATE II
DISSERTATION EVALUATION REPORT III
ACKNOWLEDGEMENT IV
ABSTRACT V
CONTENTS VI
LIST OF TABLES IX
LIST OF FIGURES X
NOTATION XII
CHAPTER 1: INTRODUCTION 01
1 General 01
1.1 Cement 02
1.2 Nanotechnology in concrete 03
1.3 Nanosilica 03
1.4 Recycled aggregates 06
1.5 Manufactured sand 09
1.6 Necessity of present study 11
1.7 Objectives 12
1.8 Organization of project 13

CHAPTER 2: LITERATURE REVIEW 14

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CHAPTER 3: METHODOLOGY AND EXPERIMENTAL INVESTIGATION 18
3.1 General 18
3.2 Materials used and test 19
3.2.1 Cement 20
3.3 Aggregates 23
3.3.1 Tests conducted on aggregates 26
3.4 water 31
3.5 Nanosilica 33

CHAPTER 4: TESTS ON CONCRETE 34

4.1 Tests on fresh concrete 34
4.1.1 Workability 34
4.1.2 Slump cone test 34
4.1.3 Compaction factor test 35
4.1.4 Mixing of concrete 36
4.1.5 Casting of specimens 36
4.1.6 Curing of specimen 38
4.2 Tests on hardened concrete 39
4.2.1 Compressive strength test 39
4.2.2 Split tensile strength test 40
4.2.3 Flexural strength test 41
4.3 Tests on durability of concrete 42
4.3.1 Acid attack 42
4.3.1.1 Procedure for volumetric analysis 43
4.3.2 Permeability test on concrete 43
4.3.2.1 Test Specimens 44
4.3.2.2 Test Procedure 44
4.4 x-ray diffraction test (XRD) 44
4.4.1 Procedure of conducting the XRD Analysis 47
4.5. Scanning Electron Microscope (SEM) 49

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CHAPTER 5: RESULTS AND DISCUSSIONS 53
5.1 Compressive strength of RAC M30 53
5.2 Split tensile strength of RAC M30 54

5.3 Flexural strength of RAC M30 55

5.4 Compressive strength of RAC M35 56
5.5 Split tensile strength of RAC M35 57
5.6 Flexural strength of RAC M35 58
5.7 Acid attacks 59
5.7.1 Acid attack of RAC M30 grade concrete of 0.1% H2SO4 59
5.7.2 Acid attack of RAC M30 grade concrete of 0.3% H2SO4 61
5.7.3 Acid attack of RAC M35 grade concrete of 0.1% H2SO4 63
5.7.4 Acid attack of RAC M35 grade concrete of 0.3% H2SO4 65
5.8 Permeability Test on concrete of RAC M30 67
5.8.1 Permeability Test on concrete of RAC M35 67
5.9 X-ray diffraction analysis 69
5.9.1 X-ray diffraction analysis RAC M30 69
5.9.2 X-ray diffraction analysis RAC M35 72
5.10 Scanning Electron Microscope images 77
5.10.1 SEM RAC M30 77
5.10.2 SEM RAC M35 78
CHAPTER 6: CONCLUSIONS AND SCOPE FOR FURTHER STUDY 79
6.1 Conclusions 79
6.2 Scope for further study 80
REFERENCES 81
IS CODES 82
APPENDIX – I 83
APPENDIX – II 87
APPENDIX – III 89
APPENDIX – IV 91
APPENDIX – V 93
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 LIST OF TABLES
Table Description Page No.
No.

3.1 Specimens cast for strength and durability tests 19

3.2 Physical properties of cement (PPC)(IS 1489(Part-1) : 1991) 27
3.3 Physical properties of fine aggregate – M-sand 28
3.4 Sieve analysis of Fine aggregate – M-sand 28
3.5 Sieve Analysis of Recycled Coarse Aggregate 29
3.6 Physical properties of Recycled coarse aggregate 29
3.7 Sieve Analysis of Coarse Aggregate 30
3.8 Physical properties of Coarse aggregate 30
3.9 Properties of Nanosilica 32
4.1 Slump cone and compaction factor values 36
5.1 Compressive Strength of Concrete of RAC M30 53

5.2 Split Tensile Strength of Concrete of RAC M30 54

5.3 Flexural Strength of Concrete of RAC M30 55
5.4 Compressive Strength of Concrete of RAC M35 56
5.5 Split Tensile Strength of Concrete of RAC M35 57
5.6 Flexural Strength of Concrete of RAC M35 58
5.7 Acid attack of RAC M30 grade concrete of 0.1% H2S04 59
5.7.1 Acid attack of RAC M30 grade concrete of 0.3% H2S04 61

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5.7.3 Acid attack of RAC M35 grade concrete of 0.1% H2S04 63
5.7.4 Acid attack of RAC M35 grade concrete of 0.3% H2S04 65
5.8 Permeability of Concrete RAC M30 67
5.8.1 Permeability of Concrete RAC M35 67
5.8.2 Standard classification of concrete (GWT): 68
5.9 Compounds and its 2θ degree for RAC M30 70
5.9.1 Compounds and its crystallite size for RCA 30 71
5.9.2 Compounds and its 2θ degree for RAC M35 73
5.9.3 Compounds and its crystallite size for RCA 35 74
5.9.4 Compound matrix for RAC M30 and RACM35 75

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 LIST OF FIGURES
Figure Description Page No.
No.

1 Pie chart for solid waste 1

1.1 Hydration of cement 3

1.2 Particle size and specific surface area related to concrete particles 4

1.3 Hydration of pure cement and hydration of cement with Nanosilica 5

cement

1.4 Recycling process of RCA 6

3.1 Nanosilica 33

4.1 Slump cone test 35

4.2 Casting of specimens 36

4.3 Casting of cubes 37

4.4 Casting of cylinders 38

4.5 Casting of prisms 38

4.6 Compressive strength test 39

4.7 Split tensile strength test 41

4.8 Flexural strength test 42

4.9 Permeability apparatus 43

4.10 Bragg ‘s law image 45

4.11 schematic of x-ray diffractometer 46

4.12 XRD instrument IIT Madras 48

4.13 Scanning Electron Microscopy instrument IIT Madras 50

4.14 Diagrammatic representation of tests on hardened concrete 52

5.1 Compressive strength of RAC M30 53

5.2 Split tensile strength of RAC M30 54

5.3 Flexural strength of RAC M30 55

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 5.4 Compressive strength of RAC M35 56

5.5 Split tensile strength of RAC M35 57

5.6 Flexural strength of RAC M35 58

5.7 weight loss due to 0.1% of H2SO4 solution on RAC M30 60

5.8 Residual compressive strength of 0.1% H2SO4 solution RAC M30 60

5.9 weight loss due to 0.3% of H2SO4 solution on RAC M30 62

5.10 Residual compressive strength of 0.3% H2SO4 solution RAC M30 62

5.11 weight loss due to 0.1% of H2SO4 solution on RAC M35 64

5.12 Residual compressive strength of 0.1% H2SO4 solution RAC M35 64

5.13 weight loss due to 0.3% of H2SO4 solution on RAC M35 66

5.14 Residual compressive strength of 0.3% H2SO4 solution RAC M35 66

5.15 Graph obtained from Xpert high score software for RAC M30 69

5.16 Graph 2θ degree vs. heights RAC M30 70

5.17 Graph obtained from Xpert high score software for RAC M35 72

5.18 Graph 2θ degree vs. heights RAC M35 73

5.19 Scanning electron microscopy of RAC M30 at 5 µm 77

5.20 Scanning electron microscopy of RAC M30 at 3 µm 77

5.21 Scanning electron microscopy of RAC M35 at 5 µm 78

5.22 Scanning electron microscopy of RAC M35 at 10 µm 78

NOTATION

ASTM - American society for testing and material

BIS - Bureau of Indian Standard

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OPC - Ordinary Portland cement

PPC - Portland Pozzolona Cement

RCA - Recycled concrete aggregate

NS - Nanosilica

IS - Indian standard

fck - Characteristic Compressive Strength of concrete

ftarget - Target mean strength at the age of 28 days

S - Standard deviation

C-S-H - Calcium Silicate Hydrate gel

CH - Calcium Hydroxide

C2S - Di-Calcium Silicate

C3S - Tri- Calcium Silicate

C3A - Tri-calcium Aluminates

C4AF - Tetra-calcium Alumino Ferrite

fb - Modulus of rupture

fct - Split tensile strength

SEM - Scanning Electron microscope

H2SO4 - Sulphuric Acid

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