DURABILITY PROPERTIES OF RECYCLED AGGREGATE CONCRETE
Jong Ho Sing
Bachelor of Engineering with Honours
'fA
(Civil Engineering)
441 2010
J19
2010
UNIVERSITI MALAYSIA SARA W AK
BORANG PENGESAHAN STATUS TESIS
ludul: DURABILITY PROPERTIES OF RECYCLED AGGREGATE CONCRETE
SESI PENGAJlAN: 2006 - 2010
Saya JONG HO SING(16393)
(HURUF BESAR)
mengaku membenarkan tesis * ini disimpan di Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dcngan syarat-syarat kcgunaan seperti berikut:
I. Tesis adalah hakmilik Universiti Malaysia Sarawak.
2. Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dibenarkan membuat salinan untuk tujuan pcngajian sahaja.
3. Membuat pendigitan untuk membangunkan Pangkalan Data Kandungan Tempatan.
4. Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dibenarkan membuat salinan tesis ini sebagai bahan pertukaran an tara institllsi pengajian tinggi.
5. .. Sila tandakan ( ., ) di kotak yang berkenaan
D
SULITo
TERHAD[~J TIDAK TERHAD
(Mengandungi makilimat yang berdarjah keselamatan atau kepcntingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972).
(Mcngandungi maklumat TERHAD yang telah ditentukan olch organisasi/
badan di mana penyclidikan dijalankan).
Disahkan oleh
Alamat tetap: LOT 6859, TMN DA SING, TMN TUNKU 98000, MIRI, SARA W AK
- Tarikh:
CATATAN
•
••
DR. DELSYE TEO CHING LEE (Nama Penyelia)
12 MAY 2010 Tarikh:
Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah, Sarjana dan Sarjana Muda.
lika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasalorganisasi berkenaan dengan mcnyatakan sekali sebab dan tcmpoh tesis ini perlu dikelaskan sebagai SULIT dan TERHAD.
The Following Final Year Project:
Title Durability Properties of Recycled Aggregate Concrete
Author Jong Ho Sing
Matric number: 16393
has been read and certified by:
Dr. Delsye Teo Ching Lee Date
(Supervisor)
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DURABILITY PROPERTIES OF RECYCLED AGGREGATE CONCRETE
,...
JONG HO SING
This project is submitted in partial fulfillment of
the requirements for the Degree of Bachelor of Engineering with Honours (Civil Engineering) 2010
,...
To my beloved family and friends
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I
ACKNOWLEDGEMENTS
First and foremost, I would to express my heartfelt gratitude towards my supervisor, Dr. Delsye Teo Ching Lee. Her constant guidance and supports keep me working on the right track throughout this whole project. Besides that, I am also grateful to all my friends that helped me during the period of laboratory works.
Apart from that, gratitude and acknowledgement is forwarded to the Paragon Concrete Sdn. Bhd for their support and cooperation in making this project possible.
Last but not least, my sincerest thanks to my family members, especially my parents for their encouraging words, continuous support and cares throughout my pursuit of degree in UNIMAS.
III
ABSTRACT
DURABILITY PROPERTIES OF RECYCLED AGGREGATE CONCRETE
JONG HO SING
In recent years, there are many studies been done on the recycled aggregate obtained from demolished concrete structures. Recycled aggregate concrete produced from recycled aggregate that obtained from demolished concrete structures has been studied and explored by the researches and engineers. The durability of the concrete is one of the most important factors to be considered in the design of new structures and when assessing the condition of existing structures. Construction of concrete is becoming increasingly complex and the importance of producing structures that are both cost effective and durable is highly emphasized during the construction process.
An understanding of concrete durability is fundamental as it is the basis that constructs the service life of new or existing structures. The objective of this research is to perform an experimental study to compare the durability properties of Natural Aggregate concrete (NAC) and recycled aggregate concrete (RAC). This includes comparison between the fresh and hardened properties of RAC with the NAC.
IV
ABSTRAK
SIFAT DURABILITAS KONKRIT AGREGAT KITAR SEMULA
JONG HO SING
Sejak kebelakangan ini, banyak kajian tentang agregat kitar semula yang diperolehi daripada "demolished concrete structures" telah dijalankan. Konkrit agregat kitar semula yang diperbuat daripada "demolished concrete structures" telah ban yak dikaji oleh para pengkaji dan jurutera. Oaya tahan konkrit merupakan salah satu faktor penting yang perlu dipertimbangkan dalam process reka cipta struktur baru dan memahami cirri-ciri struktur yang sedia ada. Pembinaan konkrit menjadi semakin kompleks dan kepentingan untuk menghasilkan struktur yang menjimat kos dan juga mempunyai daya tahan yang tinggi amat diutamakan. Kefahaman tentang daya tahan konkrit adalah dasar untuk membina struktur lama dan baru yang mempunyai tahun penggunaan yang panjang (Sandberg, 2010). Objektif kajian ini adalah menjalankan satu eksperimen untuk membandingkan ciri-ciri daya tahan bagi
"Natural Aggregate Concrete" (NAC) dan "Recycled Aggregate Concrete" (RAC).
Kajian ini juga termasuk perbandingan antara ciri-ciri "fresh" dan "hardened" bagi RACdanNAC.
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UNIVERSITI MALAYSiA SARAWAK
CONTENTS
DEDICATION
PAGES
11
ACKNOWLEDGEMENT
LIST OF ABBREVIATIONS AND NOTATIONS Xll
III
ABSTRACT IV
ABSTRAK V
CONTENTS VI
LIST OF FIGURES x
LIST OF TABLES XI
CHAPTER 1 INTRODUCTION
1.1 Background
1.2 Significance of Study 3
1.3 Sources of Recycled Concrete Aggregate (RCA) 5
1.4 Objectives 6
1.5 Scope of Work 6
1.6 Thesis Organization 7
VI
,.
CHAPTER 2 LITERA TURE REVIEW
2.1 Introduction 8
2.2 Waste material based concrete 8
2.2.1 Industrial Wastes 9
2.2.1.1 Fly Ash 9
2.2.1.2 Recycled Glass 11
2.2.1.3 Ground granulated blast furnace slag
(GGBS) 12
2.2.1.3 Recycled Concrete Aggregate (RCA) 13 2.3 Properties of Recycled Concrete Aggregate (RCA) 15
2.3.1 Specific Gravity 15
2.3.2 Moisture Content 16
2.3.3 Bulk Density 16
2.3.4 Void and Porosity 16
2.3 .5 Gradation 17
2.4 Recycled Aggregate Concrete (RAC) 17
2.4.1 Properties of Fresh Concrete 18
2.4.2 Properties of Recycled Aggregate
Concrete (RAC) 19
VII
,..
CHAPTER 3
CHAPTER 4
METHODOLOGY AND MATERIALS USED
3.1 General 20
3.2 Preparation of Materials 20
3.2.1 Recycled Concrete Aggregate (RCA) 21
3.2.2 Natural Coarse Aggregate (NCA) 23
3.2.3 Fine Aggregate 24
3.2.4 Water 26
3.2.5 Portland Cement 26
3.3 Concrete Mix design 26
3.4 Specimen testing 26
3.4.1 Properties of Fresh Concrete 28 3.4.1.1 Wet Density of Concrete 28
3.4.1.2 Slump Test 29
3.4.2 Durability Properties Tests 29 3.4.2.1 Water Absorption Test 30
3.4.2.2 Sorptivity Test 31
3.4.2.3 Concrete Impermeability Test 32
RESULTS, ANAL YSIS AND DISCUSSIONS
4.1 General 33
4.2 Recycled Concrete Aggregate (RCA) 33
4.3 Properties of Fresh Concrete 34
4.3.1 Slump Test 34
4.3.2 Concrete Wet Density 35
VIII
CHAPTERS
REFERENCES
APPENDIX
4.4
Properties of Hardened Concrete4.4.1
Compressive Strength Test4.4.2
Water Absorption Test4.4.3
Sorptivity Test4.4.4
Concrete Impermeability TestCONCLUSIONS AND RECOMMENDATIONS 5.1
5.2 5.3
General Conclusions Recommendations
36 37 39 41 43
45
46 47
48
54
IX
LISTS OF FIGURES
FIGURE PAGES
3.1 Grading Curve for Recycled Concrete Aggregate
22 3.2
Grading Curve of Natural Coarse Aggregate24
3.3
Grading Curve for Fine Aggregate25
3.4
Slump Cone29
4.1
Recycled concrete aggregate (RCA)33
4.2
Slump test of different mix35
4.3 Wet density of different mix
36
4.4
Compressive strength of hardened concrete for different mix38
4.5 Water absorption of hardened concrete for different mix40 4.6
Sorptivity index of hardened concrete for different mix42 4.7
Penetration depth of hardened concrete for different mix44
x
l
LISTS OF TABLE
TABLE PAGES
3.1
Sieve Analysis of Recycled Concrete Aggregate2l
3.2
Sieve Analysis of Natural Coarse Aggregate23
3.3
Sieve Analysis of Fine Aggregate25
3.4
Mix proportion trials27
3.5
Compressive strength and slump of mix proportion trials27
Xl
LISTS OF ABBREVIATIONS AND NOTATIONS
RCA - Recycled Concrete Aggregate RAC - Recycled Aggregate Concrete NAC - Natural Aggregate Concrete NCA - Natural Coarse Aggregate FA Fine Aggregate
SSD - Saturated Surface Dry
Xll
CHAPTER!
INTRODUCTION
1.1 Background
Recycled aggregate concrete (RAC) is the concrete produced by recycled concrete aggregate (RCA). It consists of sand, cement and RCA. RCA is defined as recycled aggregate principally comprising crushed concrete. In the recent years, the generation of construction and demolition waste has been on the rise around the world. For example, in Australia, about 40% of construction and demolition waste is produced annually. Out of the various types of construction and demolition waste produced, concrete constitutes about 80% of the total waste (Tam, 2008).
As stated in the Ninth Malaysian Plan, the government will promote the use
of recycled and reuse materials in construction industry. However, the reuse of RCA is not being practiced widely in Ma~aysian construction industry currently because there is no depletion of natural aggregates (Diah and Majid, 1998). It will be more common in the country when the sources of natural aggregate decrease (Rahman, 2009).
In the recent years, there are many studies being done on the recycled aggregate obtained from demolished concrete structures. At the same time, there is an increasing awareness in the construction industry and among the concrete manufacturer about the benefits of using available aggregate instead of wasting time
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to search for the perfect aggregate to make an ideal concrete that is suitable for all purposes (Day, 1999).
There are many researches being carried out in order to prove that RCA could be a reliable alternative as aggregate in production of concrete and most of them reported that RCA are suitable for non-structural concrete application (Sagoe,
1999).
RCA are widely applied in constructions for roadways, sidewalks, curbs, bridge substructures and superstructures, concrete shoulders, median barriers, residential driveways, erosion control, and general and structural fills. It is also being used in subbase as it can support layers such as cement-treated bases, unstabilized bases, and permeable bases. For oversized material, it can be applied at entrances of construction sites to help remove mud from truck tires (Environmental Council of Concrete Organization, 1997).
In general, limestone and granite aggregate shows higher compressive strength compared to other type of aggregate. Therefore, it is necessary to know the characteristic of RCA and the effects of using RCA in concrete. Besides that, more researches on utilization of RCA should be carried out as there are limited reliable data on the use of RCA in concrete. This research focuses on the durability properties of the RAC.
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1.2 Significance of Study
This project studies the durability properties of RAC. The precast concrete aggregate made from selected RAC can significantly contribute to an increase in concrete recycling, and the reuse of concrete recycling products in infrastructure projects. As a result, it will allow hundreds of tonnes of concrete waste to diverted from landfill sites to recycling plants, as well as reducing raw material extraction and use (Krezel, 2006).
Recycling concrete from demolition projects can result in considerable savings as it saves the cost of transporting concrete to the landfill and eliminates the cost of disposal. Due to the continuous rise in the landfill costs for construction, demolition, and land-clearing debris and the landfills become more heavily regulated, it makes the RCA an economical alternative approach in dealing the disposal of concrete from construction and demolition operations. As a consequence, there are more disposal sites are opening up and contractors are incorporating recycling into their operations to decrease disposal costs (ConcreteNetwork.com, 2009).
According to the American Concrete Pavement Association, recycling of
concrete pavement is a relatively simple process which involves breaking, removing and crushing concrete from an existing pavement into a material with a specified size and quality. In recent years, a few innovative approaches have made recycling more economical for all types of concrete pavements in recent years. The advances are development of equipment for breaking concrete pavements be they pfain, mesh
and-dowel or continuously reinforced, development of methods to remove steel that
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minImizes hand labor, and the application of crushing equipment that can accommodate steel reinforcement (ConcreteNetwork.com, 2009).
From a concrete technology viewpoint, this research contributes to the knowledge in the study of durability of RAC. This research presents a practical account and contributes to the knowledge of the design of concrete mixes using RAC, as well as on the production, placement and curing ofRAC (Krezel, 2006).
The production of concrete for construction material uses large quantity of raw materials and subsequently resulted in the depletion of natural resources available. The availability of RCA in construction industry avoid the abuse of natural resources and also fully utilize the wastes instead of going to reclamation and landfill sites. Besides that, it eliminates the development of waste piles of concrete and also decreases energy consumption in production and transportation which subsequently improves the air quality through reduced mobile source emissions (United States Department of Transportation, 2006).
Therefore, this research is focused on the durability properties of the RAC as the durability of the concrete is one of the most important factors to be considered in the design of new structures and when assessing the condition of existing structures.
Construction of concrete is becoming increasingly complex and the importance of producing structures that are both cost effective and durable is highly emphasized during the construction process. An understanding of concrete durability is fundamental as it is the basis that constructs the service life of new or existing structures (Sandberg, 2010).
4
1.3 Sources of Recycled Concrete Aggregate (RCA)
RCA involves breaking, remOVing, and crushing existing concrete into a material in specified size and quality (Portland Cement Organization, 2009). RCA could be produced from recycled precast elements and cubes after testing. From this source, the RCA is considerably clean with cement paste adhering to it. Other than precast elements and cubes, RCA could be obtained from demolition waste which is contaminated by ceramic, wood, plastics, paper and iron etc (Rao, 2005). RCA should be free from these contaminations in the production of concrete.
For this study, the RCA were produced from crushing cubes that were previously tested to compressive strength. These cubes can be crushed and screened through portable, mobile or stationary recycle plants instead of being discarded after testing and increase disposal in landfill.
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1.4 Objectives
The objectives of this study are:
i) To investigate the durability properties of RAC.
ii) To compare the durability properties between RAC with Natural aggregate concrete (NAC).
1.5 Scope of Work
In this study, RCA is used as coarse aggregate for production of concrete.
RAC consisted of RCA, sand, water and cement. In order to produce a mix design, physical and mechanical properties for RCA, conventional coarse aggregate and natural fine aggregate are determined. Various tests are carried out to investigate the properties of Natural coarse aggregate (NCA), RCA and natural fine aggregate. The properties are specific gravity; absorption; bulk density; moisture content and sieve analysis. The concrete produced with NCA are taken as control mix. A comparison between concrete made by 50% and 100% replacement of RCA as well as 100%
replacement of saturated surface dry (SSD) RCA with the control mix are made.
The curing method for both hardened RAC and hardened NAC is water bath curing. The durability tests such as water absorption test, sorptivity test and concrete impermeability test are carried out to determine the durability properties of the RAC and NAC at 3-day, 7-day, 28-day and 56-day. Next, slump test is carried out to determine the slump of fresh concrete. Water absorption test is the test that measures water absorbed by an immersed core sample into the water.
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1.6 Thesis Organization
There are five chapters in this thesis including:
1. Chapter 1: Introduction
11. Chapter 2: Literature Review
lll. Chapter 3: Methodology
IV. Chapter 4: Results, Analysis and Discussions v. Chapter 5: Conclusion and Recommendations
Chapter 1 introduces the project as a whole. Chapter 2 discussed about related topics or researches on this project. These topics are mainly definition and properties of aggregate and concrete. Chapter 3 elaborates on the source of material and the steps involved in implementation. Results from the laboratory tests in table, graphical form and discussion on the results are presented in Chapter 4. Lastly, the overall findings with recommendations for future researches are discussed in Chapter 5.
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CHAPTER 2
LITERATURE REVIEW
2.1 Introduction
The literature review provides the necessary background information on RCA and also presents the knowledge and examples of successful uses of waste materials in concrete technology with a strong focus on RCA. The characteristic of RCA are reviewed in term of their properties. It also presents a review of available literature between conventional coarse aggregate and RCA properties including particle size distribution, specific weight, bulk density and the water absorption.
2.2 Waste Material Based Concrete
Nowadays, many investigations have been done to develop concrete using agricultural and industrial waste materials due to the lower cost that only made up of processing, handling and transportation. The most important issues are the stability and durability of products made of concrete using waste materials over expected life span.
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2.2.1 Industrial Wastes
An industrial waste is a type of waste produced by industrial activity, such as that factories, mills and mines. It has existed since the outset of the industrial revolution. Types of industrial waste are fly ash, recycled grass, ground granulated blast furnace slag (aaBS) and RCA.
2.2.1.1 Fly ash
Fly ash is the most well known cement replacement material. Fly ash consists of the non-combustible mineral portion of the coal. They are usually found in power plants powered by coal. It is created from the combustion of coal. It is most commonly found in huge amount at coal power plants. Fly ash mainly consists of Silicon Dioxide (Si02) and Calcium Oxide (CaO).
Fly ash is generally a waste materia} that is reused as partial cement replacement material because of its pozzolanic properties. When combined with lime Calcium Hydroxide (Ca(OH)2), they will form a cementitious material together.
Concrete containing fly ash are stronger, more durable and more resistant to chemical attacks. The usual type of fly ash used is Class F. Class F fly ash contains less than 10% lime. Therefore Class F fly ash requires to be mixed with Portland --cement and water in order to react and form cementitious compounds. It can be used
to replace up to 30% of the Portland cement (Headwaters, n.d.).
Usage of fly ash as partial cement replacement enables conservation of natural resources as well as protecting the land because normally fly ash will be
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