i

UTILIZATION OF GEOPOLYMER FLY ASH AS CONCRETE BINDER

A Thesis Outline Submitted to

the faculty of Department of
Civil Engineering
College of Engineering and Information Technology
Cavite State University
Indang, Cavite

In partial fulfillment
of the requirement for the degree of
Bachelor of Science in Civil Engineering

RONALD JOSHUA B. PANALIGAN

MARK JASPER O. VILLANUEVA
June 2020
 ii

BIOGRAPHICAL DATA

The author, Ronald Joshua B. Panaligan, was born on February 16, 1997 in

Naic, Cavite. He is the eldest child among the three children of Mr. Rodelito B.

Panaligan and Mrs. Amalia N. Baltazar.

He completed his elementary education in 2009 at Naic Elementary School in

Naic, Cavite and her secondary education at Cavite National Science High School in

2013. In 2015, he took and passed the entrance examination at Cavite State

University (CvSU) and studied under the Bachelor of Science in Civil Engineering

program. He was a member of the Philippine Institute of Civil Engineers, Inc., Cavite

State University – Student Chapter (PICE CvSU - SC).

 iii

BIOGRAPHICAL DATA

The author, Mark Jasper O. Villanueva, was born on May 26, 1997 in UMC

Dasmariñas, Cavite. He is recently residing at Langkaan II Dasmariñas City, Cavite.

He is the second child among the three children of Mr. Manolo C. Villanueva and

Mrs. Jocelyn O. Villanueva

He completed his elementary education in 2010 at Francisco E. Barzaga

Memorial School in Dasmariñas City, Cavite and his secondary education at

Langkaan II National High School in City Homes Resortville, Langkaan II,

Dasmariñas City, Cavite in 2014. In the same year, he took and passed the entrance

examination at Cavite State University (CvSU) and studied under the Bachelor of

Science in Civil Engineering program. He was a member of the Philippine Institute of

Civil Engineers, Inc., Cavite State University – Student Chapter (PICE CvSU - SC).
 iv

PERSONAL ACKNOWLEDGEMENT

This design project became a reality with the kind support, patience,

knowledge faith, time and effort of many individuals. The author would like to express

their sincere and endless gratitude to the following individuals whom in their own way

contributed to the completion of this design project:

Foremost, the author wants to offer this endeavor to our GOD Almighty for the

wisdom He bestowed upon him, the strength, peace of mind and good health in order

to finish this study.

ANONG POSITION NI MAM BAGO SA STUDY
Engr. Cene M. Bago, for her support, encouragement, advices, and for her

patience and time to answer questions regarding the geopolymer concrete;

Engr. Marcus Ceazar V. Austria, technical critic, for his support and

recommendations regarding the study as well as his shared knowledge on the

related studies;

Engr. Roslyn P. Peña, unit research coordinator, for her advices and support

given to accomplish this project;

Engr. Rosly P. Peña, college research coordinator, and Dr. David L. Cero,

college dean, for making the title and manuscript possible;

Engr. Roxcell J. Gloriani, for sharing her knowledge and support that helped

the author to fully understand and accomplish the study.

Team Geopolymer (Mark Jasper, Edmon and Raphael), and Maechie, for

sharing their time, resources, and encouragement for the completion of this project.

His classmates; most especially the Chicken Feet Gang, Arc, Patrick, Danly,

Ichan, Richmond, and Rhenzel for the friendship, effort to share their knowledge,

encouragement and support for the authors to complete this project;

His co-author, Mark Jasper, for his time, support, patience and for being kind

and understanding partner;

 v

His family, Mama, Papa, Ate Ivy, Ate Menmen, Aileen Joy, and Bryan James

for their heartfelt support, encouragement and unconditional love, and for serving as

an inspiration for him to pursue this course;

Mrs. Adea and her family, for feeding, keeping him safe and letting him stay

to conduct the experiment in their place in Silang, Cavite.

HIS
Their CE family, Civil Engineering Students Batch 2019-2020 especially

Lance Millennard Q. Bernal, for the friendship and bonding, and their seniors for

sharing their knowledge and support to accomplish this project;

Above all, to Almighty God for His never-ending love and for providing him

strength, knowledge, guidance, and immeasurable support for the completion of this
INULIT MO ACKNOWLEDGEMENT MO KAY GOD, MERON KA NA SA UNA
design project.

The author would like to thank everybody who played an important role for

the successful realization of this study.

RONALD JOSHUA PANALIGAN

 vi

PERSONAL ACKNOWLEDGEMENT

The research project has come to its accomplishment with the efforts,

support, time and faith of many individuals. The author would like to express its

gratitude to the following individuals for their contributions to the completion of the

research project.

Engr. Cene M. Bago, research project adviser, for her advices, guidance, and

the knowledge that she shared to the researchers regarding to geopolymer concrete

and different things about a research project.

Engr. Marcus Ceazar V. Austria, technical critic, to his support and

recommendations regarding the research project and boosting the confidence of the

researchers to the accomplishment of the project.

Engr. Ralph T. Crucillo for supporting the researchers for additional

knowledge about the research topic, for his supports and prayers during the

development of the project and for the advices as their professor and as their former

Pice Cvsu-SC president.

Engr. Roslyn P. Peña, college research coordinator, and Dr. David L. Cero

college dean, form making the title, manuscript and final defense possible.

To the Adea‟s family for giving them a place to work and for the different

support they had given to authors.

His co-author Ronald Joshua B. Panaligan, for his supports and cooperation

for the accomplishment of the research project.

His mother Jocelyn O. Villanueva for always supporting him in his challenges

in life and for financial support.

His brothers, Mark Jigger O. Villanueva and Mark Lester O. Villanueva for

also supporting him in his entire college life.

Above all, to God for giving him his life, for supporting everyone including him

on their dreams, for the skills and talents that are given to him, and for the
 vii

knowledge, determination and courage he has given to accomplish this research

project.

MARK JASPER VILLANUEVA

 viii

ABSTRACT

PANALIGAN, RONALD JOSHUA B. and VILLANUEVA, MARK JASPER O.

Comparative Study of Portland Cement Concrete and Geopolymer Fly Ash
Concrete. Undergraduate.Thesis. Bachelor of Science in Civil Engineering. Cavite
State University, Indang, Cavite. May 2020. Adviser: Engr. Cene M. Bago

Geopolymer concrete is a type of concrete that is made by reacting aluminate

and silicate bearing materials with a caustic activator. Commonly, waste materials

such as fly ash or slag from iron and metal production are used, which helps lead to

a cleaner environment. Owing to its pozzolanic properties, fly ash is used as a

replacement for Portland cement in concrete in this study.

The purpose of this study is to determine, compare and investigate the

different advantages and disadvantages of using Fly Ash Geopolymer Concrete in

terms of its mechanical properties specifically its compressive strength and its

economic impact compared to Conventional Portland Cement Concrete. Also, this

study aims to know what proportion of Fly Ash to caustic activator is best suitable to

obtain the highest strength of Geopolymer Concrete.

The proportions made were the following: Fly Ash 61%: Alkali Activators 39%,

Fly Ash 73%: Alkali Activators 27%, Fly Ash 67%: Alkali Activators 33%. Slump
CYLINDRICAL MOLD?
results were measured and then the samples were placed in a cylinder. Samples
MOLD
were removed from the cylinder after a day and were cured underwater.

Compressive strength of every proportion was tested at Cavite Testing Center every

7th, 14th, and 28th day.

Test results showed that the Geopolymer Concrete with the proportion of 73%

Fly Ash: 27% Alkali Activators gained the highest strength. The results of the study

demonstrated that there is a significant relationship between the proportions of the

alkali activators and fly ash. During specimen preparation, it was observed that

maximum proportion (73% Fly Ash, 27% Alkali Activators) produced a watery mixture

due to higher content of Alkali activators but has the lowest amount of fly ash.
 ix

Minimum proportion (61% Fly Ash, 39% Alkali Activators) has the highest content of

fly ash and lowest amount of alkali activators, producing a mixture of low

consistency. From the three mixtures tested, the average proportion (67%, 33%)

develops the highest compressive strength. Maximum proportion ranks second, then

the minimum proportion in strength. It can be inferred from the result that alkali

activators, as a binding agent, works best with proper amount of fly ash. Too much fly

ash may not be mixed properly with the binder, and too much alkali activator may just

produce water-like mixture. Just like the conventional PCC wherein proper water

cement ratio must be observed, right proportion of fly ash and alkali activator must be

made to attain the desired strength of concrete.

PASINGIT AKO NUNG ECONOMIC EVALUATION NG STUDY NYO.

 x

TABLE OF CONTENTS

Page

BIOGRAPHICAL DATA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

PERSONAL ACKNOWLEDGMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . iv

ABSTRACT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii

INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Statement of the Problem.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Objectives of the Study. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Significance of the Study. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 HMM, BAKA

MAY IGAGANDA
PA NG
Scope and Limitation of the Study. . . . . . . . . . . . . . . . . . . . . . 3 FORMAT TO
MAY BUILT
Time and Place of the Study. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 IN WORD
NETO
Definition of Terms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

REVIEW OF RELATED LITERATURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

METHODOLOGY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

RESULTS AND DISCUSSION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

SUMMARY, CONCLUSIONS AND RECOMMENDATIONS. . . . . . . . . . . . . . . 37

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

REFERENCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NASAN TO

APPENDICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
 1

UTILIZATION OF GEOPOLYMER FLY ASH AS CONCRETE BINDER

Ronald Joshua B. Panaligan

Mark Jasper O. Villanueva

An undergraduate design project manuscript submitted to the faculty of Department

of Civil Engineering, College of Engineering and Information Technology, Cavite
State University, Indang, Cavite in partial fulfillment of the requirements for the
degree of Bachelor of Science in Civil Engineering with Contribution No. ________.
Prepared under the supervision of Engr. Cene M. Bago.
___________________________________________________________________

INTRODUCTION

Concrete is the world‟s most versatile, durable and reliable construction

material. Next to water, concrete is the most used material, which required large

quantities of Portland Cement. Ordinary Portland Cement production is the second

only to the automobile as the major generator of carbon di oxide, which polluted the

atmosphere. In addition to that large amount energy was also consumed for the

cement production.

Portland cement and fly ash can both be key ingredients in concrete mixes. Although
INDENTED ATA TO
concrete is sometimes use interchangeable with cement, concrete is actually a

mixture of a base with larger aggregate materials. The aggregates are typically

different types of stone, but the base is most often Portland cement, a mixture of

clays, metallic elements and minerals like calcium and silica. While Portland cement

can have fly ash in it, fly ash concrete is typically made with a base of full fly ash

instead of any Portland cement.

Fly ash is a fine powder that is a byproduct of burning pulverized coal in

electric generation power plants. Fly ash is a pozzolan, a substance containing

aluminous and siliceous material that forms cement in the presence of water. When

mixed with lime and water, fly ash forms a compound similar to Portland cement.
 2

This makes fly ash suitable as a prime material in blended cement, mosaic tiles, and

hollow blocks, among other building materials. When used in concrete mixes, fly ash

improves the strength and segregation of the concrete and makes it easier to pump.

The Cement production generated carbon dioxide, which pollutes the

atmosphere. The Thermal Industry produces a waste called fly ash which is simply

dumped on the earth, occupies larges areas. The waste water from the Chemical

Industries is discharged into the ground which contaminates ground water. By

producing Geopolymer Concrete all the above-mentioned issues shall be solved by

rearranging them.

Waste Fly Ash from Thermal Industry + Waste water from Chemical

Refineries = Geopolymer concrete. Since Geopolymer concrete does not use any

cement, the production of cement shall be reduced and hence the pollution of

atmosphere by the emission of carbon di oxide shall also be minimized.

Therefore, the study of the potential of making geopolymer binder is expected

to be one solution to lessen the release of Carbon Dioxide in the process of

producing conventional Portland cement in order to be more easily accepted and

applied by the public.

WALA BANG SPACE DITO PATI DUN SA IBA
Statement of the Problem
EFFECTIVENESS AND EFFICIENCY OF (SUGGESTION LANG 'TO)
This study aspires to know the utilization of geopolymer fly ash as substitute
PARANG NAKAHANG UNG UNANG SENTENCE.
to cement as binder (PERIOD) PAVERIFY NA DIN.
"ASPIRES TO KNOW" WHAT?
This study answered the following questions:

1. What is the best proportion of fly ash to alkali activating solution as

geopolymer binder?

2. What are the advantages and disadvantages of using geopolymer binder?

Objectives of the Study

The main objective of the study is to compare the compressive strength and

the slump test result of Fly Ash Geopolymer Concrete with conventional Portland
HINDI BA DAPAT IN LINE ANG OBJECTIVES OF THE STUDY
Cement Concrete. SA STATEMENT OF THE PROBLEM
 3

Specifically, this study aimed to:

1. determine the most suitable proportion of fly ash to alkali activators as

geopolymer binder.

2. identify the differences between the compressive strength and the slump test
SAME NG MAIN
OBJECTIVE NYO?
result of Portland Cement Concrete and Fly Ash Geopolymer Concrete.

3. know the advantages and disadvantages of using Geopolymer concrete.

Significance of the Study

Next to water, concrete is the most used material, which required large

quantities of Portland Cement. Ordinary Portland Cement production is the second

only to the automobile as the major generator of carbon dioxide, which polluted the

atmosphere. In addition to that, large amount energy was also consumed for the

cement production. Hence, it is inevitable to find an alternative material to the

existing most expensive, most resource consuming Portland Cement. The Thermal

Industry produces a waste called fly ash which is simply dumped on the earth,
I DONT THINK
NA KAILANGANG NAKA
CAPITALIZE UNG occupies larges areas. The waste water from the Chemical Industries is discharged
IBA NYONG NOUN DITO
into the ground which contaminates ground water. By producing Geopolymer

Concrete all the above-mentioned issues shall be solved by rearranging them.

Scope and Limitation

The main focus of the study is to produce a concrete which does not use

Portland Cement as a binder. The focal point will be on the technical evaluation and

analysis of the properties of geopolymer concrete. Class F fly ash from coal which is

activated using chemicals such as sodium hydroxide and sodium silicate will be

used. The following tests will be conducted: Slump Test, Compressive Strength Test

and Unit Weight Test.

Time and Place of the Study

The study was conducted at Cavite State University - Indang Cavite under

supervision of Engr. Cene M. Bago from December 2019 to May 2020. The fly ash
 4
PAST TENSE

was given by the Pozzolanic Philippines Inc. and is obtain from Calaca, Batangas

while the sodium hydroxide and sodium silicate were bought from Alyson‟s Chemical

Enterprises Inc. located in G. Araneta Quezon City, Manila. The samples were mixed

at Adea‟s residence at Barangay Biga II Silang, Cavite and the cylinder samples

were cured at the same location for 7 days, 14 days, and 28 days. The concrete

cylinders were test under compression in Cavite Testing Center (Material Testing

Laboratory) at Barangay Lalaan II Silang, Cavite.

Definition of Terms

Aggregate. It is a granular material, such as sand, gravel, crushed stone,

crushed hydraulic-cement concrete, or iron blast-furnace slag, used with a hydraulic

cementing medium to produce either concrete or mortar.

Cement. It is an adhesive or glue, which when set binds particles of fine

aggregate together to produce mortar.

Cementitious Materials. Any of various building materials which may be

mixed with a liquid, such as water, to form cement base substance, and to which an

aggregate may be added; includes cements, limes, and mortar

Compressive strength. It is the capacity of a material or structure to

withstand loads tending to reduce size, as opposed to tensile strength, which

withstands loads tending to elongate.

Concrete. It is a mixture of Portland cement or any other hydraulic cement,

fine aggregate, coarse aggregate, and water, with or without admixtures.

Geopolymer Concrete. a type of concrete that is made by reacting aluminate

and silicate bearing materials with a caustic activator. Commonly, waste materials

such as fly ash or slag from iron and metal production are used, which helps lead to

a cleaner environment.
 5

Sand. It is a naturally occurring granular material composed of finely

divided rock and mineral particles. It is defined by size, being finer than gravel and

coarser than silt.

Silica. It is also known as Silicon dioxide (SiO2) and usually present in

cement to the extent of about 30 percent.

 6

REVIEW OF RELATED LITERATURE

Use of concrete is globally accepted due to ease in operation, mechanical

properties and low cost of production as compared to other construction materials.

Unimportant ingredient in the conventional concrete is the Portland cement.

Production of Portland cement is increasing due to the increasing demand of

construction industries. Therefore, the rate of production of carbon dioxide released

to the atmosphere during the production of Portland cement is also increasing.

Generally, for each ton of Portland cement production, releases a ton of carbon

dioxide in the atmosphere. The greenhouse gas emission from the production of

Portland cement is about 1.35 billion tons annually, which is about 7 % of the total

greenhouse gas emissions. Moreover, cement production also consumes significant

amount of natural resources. Therefore, to reduce the pollution, it is necessary to

reduce or replace the cement from concrete by other cementitious materials like fly

ash, blast furnace slag, rice husk ash, etc.

Fly ash is a by-product of pulverized coal blown into a fire furnace of an

electricity generating thermal power plant. According to the survey, the total fly ash

production in the world is about 780 million tons per year but utilization is only about

17–20 % [2, 3]. In India more than 220 million tons of Fly ash is produced annually.

Out of this, only 35–50 % fly ash is utilized either in the production of Portland

pozzolana cement, workability improving admixture in concrete or in stabilization of

soil. Most of the fly ash is disposed off as a waste material that covers several

hectares of valuable land. The importance of using fly ash as a cement replacing

material is beyond doubt. Malhotra, recommended replacing cement by fly ash up to

60 % known as high volume fly ash concrete. But it was observed that the pozzolanic

action of fly ash with calcium hydroxide formed during the hydration of cement is very

slow. The particles of size less than 45 μmare responsible for pozzolanic reaction.

Higher size particles present in fly ash acts as filler.

 7

Therefore, for complete replacement of cement by fly ash and to achieve the

higher strength within a short period of curing, Davidovits, suggested the activation

process of pozzolanic material that are rich in silica and alumina like fly ash with

alkaline elements at certain elevated temperature. Fly ash when comes in contact

with highly alkaline solutions forms inorganic alumino–silicate polymer product

WALA BA TALAGANG YEAR
UNG IBANG
REFERENCES NYO? yielding polymeric Si–O–Al–O bonds known as Geopolymer.
PACHECK NA LANG SGURO
NUNG MGA CITATIONS. To produce concrete of desired strength, various mix proportioning methods
KAHIT AFTER NA
MAHCECKAN NINA MAM BAGO
are used on the basis of type of work, types, availability and properties of material,

field conditions and workability and durability requirements. Rangan have proposed

the mix design procedure for production of fly ash based geopolymer concrete

whereas Anuradha et al. have presented modified guidelines for mix design of

geopolymer concrete using Indian standard code.

As geopolymer concrete is a new material in which cement is totally replaced

by ash and activated by alkaline solutions. Chemical composition, fineness and

density of fly ashes are different from cement. Similarly, in cement concrete, water

plays main role during hydration process while water come out during polymerization

process as in case of geopolymer concrete. Therefore, it is necessary to develop a

new mix design procedure for geopolymer concrete to achieve desired strength at

required workability. (Subhash v. Pantakar,2015)

Geopolymer cement

From a terminological point of view, geopolymer cement is a binding system

that hardens at room temperature, like regular Portland cement. If a geopolymer

compound requires heat setting, it may not be called geopolymer cement but rather

geopolymer binder. Geopolymer cement is an innovative material and a real

alternative to conventional Portland cement for use in transportation infrastructure,

construction and offshore applications. It relies on minimally processed natural

materials or industrial byproducts to significantly reduce its carbon footprint, while

 8

also being very resistant to many of the durability issues that can plague

conventional concretes.

Creating geopolymer cement requires an alumina silicate material, a user-

friendly alkaline reagent (sodium or potassium soluble silicates with a molar ratio MR

SiO2:M2O>1,65, M being Na or K) and water. Room temperature hardening relies on

the addition of calcium cations, essentially iron blast furnace slag.

Geopolymer cements cure more rapidly than Portland-based cements. They

gain most of their strength within 24 hours. However, they set slowly enough that

they can be mixed at a batch plant and delivered in a concrete mixer. Geopolymer

cement also has the ability to form a strong chemical bond with all kind of rock-based

aggregates. On March 2010, the US Department of Transportation Federal Highway

Administration released a TechBrief titled Geopolymer Concrete that states: The

production of versatile, cost-effective geopolymer cements that can be mixed and

hardened essentially like Portland cement represents a game changing

advancement, revolutionizing the construction of transportation infrastructure and the

building industry.

There is often confusion between the meanings of the two terms 'geopolymer

cement' and 'geopolymer concrete'. A cement is a binder whereas concrete is the

composite material resulting from the addition of cement to stone aggregates. In

other words, to produce concrete one purchases cement (generally Portland cement

or Geopolymer cement) and adds it to the concrete batch. Geopolymer chemistry

was from the start aimed at manufacturing binders and cements for various types of

applications.

Alkali-activated materials vs Geopolymer cements

 9

Geopolymerization chemistry requires appropriate terminologies and notions

that are evidently different from those in use by Portland cement experts. Numerous

publications on Geopolymer summarize how geopolymer cements belong to the

category of Inorganic polymer. On this matter, the Australian Geopolymer Alliance

outlines on his web site the following statement: " Joseph Davidovits developed the

notion of a geopolymer (a Si/Al inorganic polymer) to better explain these chemical

processes and the resultant material properties. To do so required a major shift in

perspective, away from the classical crystalline hydration chemistry of conventional

cement chemistry. To date this shift has not been well accepted by practitioners in

the field of alkali activated cements who still tend to explain such reaction chemistry

in Portland cement terminology. Indeed, geopolymer cement is sometimes mixed up

with alkali-activated cement and concrete. They were originally known under the

names "soil silicate concretes" and "soil cements". Because Portland cement

concretes can be affected by the deleterious Alkali-aggregate reaction (AAR) or

Alkali-silica reaction (ASR). Nevertheless, several cement scientists continue to

promote the idea of alkali-activated materials or alkali-activated geopolymers. These

alkali-activated materials cements encompass the specific fields of alkali-activated

slags, alkali-activated coal fly ashes, blended cements. However, it is interesting to

mention the fact that geopolymer cements do not generate any of these deleterious.

Geopolymer cement categories

The categories comprise:

 Slag-based geopolymer cement.

 Rock-based geopolymer cement.

 Fly ash-based geopolymer cement

a. type 1: alkali-activated fly ash geopolymer.

b. type 2: slag/fly ash-based geopolymer cement.

 Ferro-sialate-based geopolymer cement.

 10

Fly ash-based geopolymer cements

Later on, in 1997, building on the works conducted on slag-based

geopolymeric cements, on the one hand and on the synthesis of zeolites from fly

ashes on the other hand, Silverstrim et al. and van Jaarsveld and van Deventer

developed geopolymeric fly ash-based cements. Silverstrim et al. US Patent

5,601,643 was titled 'Fly ash cementitious material and method of making a product'.

Type 2: slag/fly ash-based geopolymer cement (user-friendly):

Room-temperature cement hardening. User-friendly silicate solution + blast

furnace slag + fly ash: fly ash particles embedded in a geopolymeric matrix with

Si:Al= 2, (Ca,K)-poly(sialate-siloxo).

Carbon dioxide emission during manufacture of Portland cement clinker

CITATIONS, PLS. Ordinary cement, often called by its formal name of Portland cement, is a

serious atmospheric pollutant. Indeed, the manufacture of Portland cement clinker

involves the calcination of calcium carbonate according to the reaction:

5CaCO3 + 2SiO2 → (3CaO,SiO2)(2CaO,SiO2) + 5CO2

The production of 1 ton of Portland clinker directly generates 0.55 tons of chemical-

CO2 and requires the combustion of carbon-fuel to yield an additional 0.40 tons of

carbon dioxide.

To simplify: 1 T of Portland cement = 0.95 T of carbon dioxide

The only exceptions are so-called „blended cements‟, using such ingredients as coal

fly ash, where the CO2 emissions are slightly suppressed, by a maximum of 10%-

15%. There is no known technology to reduce carbon dioxide emissions of Portland

cement any further. On the opposite, Geopolymer cements do not rely on calcium

carbonate and generate much less carbon dioxide during manufacture, i.e. a

reduction in the range of 40% to 80-90%. The Portland cement industry reacted

strongly by lobbying the legal institutions so that they delivered carbon dioxide

emission numbers, which did not include the part related to calcium carbonate

decomposition, focusing only on combustion emission. It is calculated that world

 11

cement production of 1.4 billion tons a year produces 7 % of the world‟s current

carbon dioxide emissions. Fifteen years later (2012), the situation has worsened with

Portland cement carbon dioxide emissions approaching 3 billion tons a year. The fact

that the dangers to the world‟s ecological system from the manufacture of Portland

cement is so little known by politicians and public makes the problem all the more

urgent: when nothing is known, nothing is done. This situation clearly cannot

continue if the world is going to survive.

Properties of geopolymer cements

According to the reaction process, two factors have a direct effect on the final

product, namely, the aluminosilicate and activator. Properties of the solid

aluminosilicate will directly affect the dissolution process and the subsequent

reaction, while the liquid activator will partially or completely dissolve the solid raw

material and determine break and recombination of the aluminosilicate structure,

polycondensation and charge balance in the reaction system.

The properties of the hydration products of geopolymers are strongly affected

by the type of activator; the activator anion plays an important role in microstructural

development. The sodium hydroxide, silicate, carbonate and sulphate, sodium

hydroxide and sodium silicate

are the more commonly used alkaline activating agents. A few studies have also

been carried out with potassium hydroxide or sodium carbonate as the activating

agent.

Geopolymers have also been shown to exhibit superior mechanical properties

to those of Ordinary Portland Cement. They are the results of the hardening of the

alkali activated aluminosilicate constituent of the binding system and the action of the

technologic conditions of the hardening.

Geopolymers exhibit a wide range of properties and characteristics that make

them suitable for diverse applications, depending on the raw materials used in
 12

polymer synthesis. In fact, the starting raw materials play a vital role in the

geopolymerisation reactions and control the chemical composition and microstructure

of the final geopolymeric products.

Geopolymers have received considerable attention because of their low cost,

excellent mechanical and physical properties, low energy consumption and reduced

“greenhouse emissions” during the elaboration process.

CITATIONS PLS
Processing factors

A considerable number of variables are involved in alkaline activation, most

prominently the composition of the prime materials (particle size, vitreous phase

content, silica and reactive BAT MAY SPACE

alumina content); type and concentration of the alkaline activator; liquid/solid ratio;

curing

temperature and time; and moisture conditions during initial curing. These variables

have been amply studied in the literature because they affect the degree of reaction,

the mineralogical composition and microstructure of the reaction products and

ultimately the physical-mechanical properties of the material.

Materials

Most waste materials such as fly ash, blast furnace slag and mine tailings

contain sufficient amounts of reactive alumina and silica that can be used as source

materials for in situ geopolymerisation reactions. Nevertheless, the most studies

have used the source materials on an arbitrary basis without consideration of the

mineralogy or paragenesis of the individual minerals. It is important to note that the

interrelationship between mineralogy and reactivity of individual minerals is extremely

complex, and so further research on the ability of a wide variety of different materials

to undergo geopolymerisation is required in order to elucidate the underlying

chemical mechanisms. It is reasonable to assume that the type and nature of the

starting materials used will directly affect the final physical and chemical properties of
 13

a geopolymer derived from waste materials. The current work therefore investigates

the effect of various compositions of fly ash and kaolinite mixes on the physical and

chemical properties of geopolymers.

It was shown that the water content, curing as well as calcining conditions

affect the final properties of a geopolymer.

Parameters Considered for Mix Proportioning of Geopolymer Concrete

INDENTION PLS For the development of fly ash based geopolymer concrete mix design method,

detailed investigations have been carried out and following parameters were selected

on the basis of workability and compressive strength.

A. Fly ash
REQUIRED BANG MAY SPACE DITO?
Quantity and fineness of fly ash plays an important role in the

activation processor geopolymer. It was already pointed out that the strength

of geopolymer concrete increases with increase in quantity and fineness of fly

ash. Similarly, higher fineness shows higher workability and strength with

early duration of heating. So, the main emphasis is given on quantity and

fineness of fly ash in the development of mix proportioning procedure of

geopolymer concrete.

B. Alkaline Activators

In the present investigation, sodium based alkaline activators are

used. Single activator either sodium hydroxide or sodium silicate alone is not

much effective as clearly seen from past investigation. So, the combination of

sodium hydroxide and sodium silicate solutions are used for the activation of

fly ash based geopolymer concrete. It is observed that the compressive

strength ofgeopolymer concrete increases with increase in concentration of

sodium hydroxide solution and or sodium silicate solution with increased

viscosity of fresh mix. Due to increase in concentration of sodium hydroxide

 14

solution in terms of molarity (M) makes the concrete more brittle with

increased compressive strength. Secondly, the cost of sodium hydroxide solid

is high and preparation is very caustic. Similarly, to achieve desired degree of

workability, extra water is required which ultimately reduce the concentration

of sodium hydroxide solution. So, the concentration of sodium hydroxide was

maintained at 13 M while concentration of sodium silicate solution contains

Na2Oof16.37 %, SiO2of 34.35 % and H2O of 49.72 % is used as alkaline

solutions. Similarly, sodium silicate-to-sodium hydroxide ratio by mass was

maintained at1 which set cubes within 24 h after casting and gives fairly good

results of compressive strength.

C. Water

From the chemical reaction, it was observed that the water comes out

from the mix during the polymerization process. The role of water in the

geopolymer mix is to make workable concrete in plastic state and do not

contribute towards the strength in hardened state. Similarly, the demand of

water increases with increase in fineness of source material for same degree

of workability. So, the minimum quantity of water required to achieve desired

workability is selected on the basis of degree of workability, fineness of fly ash

and grading of fine aggregate.

D. Aggregates

Aggregates are inert mineral material used as filler in concrete which

occupies70–85 % volume. So, in the preparation of geopolymer concrete, fine

and coarse aggregates are mixed in such a way that it gives least voids in the

concrete mass. This was done by grading of fine aggregate and selecting

suitable fine-to-total aggregate ratio. Workability of geopolymer concrete is

also affected by grading of fine aggregate similar to cement concrete.

 15

E. Degree of Heating

For the development of geopolymer concrete, temperature and

duration of heating plays an important role in the activation process. In the

present investigation, cubes were demolded after 24 h of casting and then

place in an oven for heating at 60 °C for a period of 24 h. After specified

degree of heating, oven is switched off and cubes are allowed to cool down to

room temperature in an oven itself. Then compression test is carried out on

geopolymer concrete cubes after a test period of 7 days. Test period is the

period considered in between testing cubes for compressive strength and

placing it in normal room temperature after heating. Table 1 shows the effect

of duration of heating and test period on compressive strength of geopolymer

concrete. It is observed that the compressive strength of geopolymer concrete

increases with increase in duration and test period. From the design point of

view, 24 h of oven curing at 60 °C and tested after a period of 7 days was

fixed as per past research.

F. Water-to-geopolymer binder ratio

The ratio of total water (i.e. water present in solution and extra water if

required) to material involve in polymerization process (i.e. fly ash and sodium

silicate and sodium hydroxide solutions) plays an important role in the

activation process. Rangan suggested the water-to-geopolymer solid ratio in

which only solid content in solution and fly ash is considered. But the

calculation is tedious and water present in solution indicates the concentration

of solution itself. So, in the present investigation, water-to-geopolymer binder

ratio is considered. From the investigation, it is observed that the compressive

strength reduces with increase in water-to-geopolymer binder ratio similar to

water-to-cement ratio in cement concrete. At water-to-geopolymer binder ratio

of 0.25, the mix was very stiff and at 0.40, the mix was segregated. Similarly,
 16

water come out during polymerization process and does not contribute

anything to the strength. So, water-to-geopolymer binder ratio is maintained

at 0.35which gives better results of workability and compressive strength.

G. Solution to fly ash ratio

As solution (i.e. sodium silicate + sodium hydroxide) to fly ash ratio

increases, strength is also increases. But the rate of gain of strength is not

much significantbeyond solution to fly ash ratio of 0.35. Similarly, the mix was

more and more viscous with higher ratios and unit cost is also increases. So,

in the present mix design method, solution-to-fly ash ratio was maintained at

0.35. (Subhash v. Pantakar,2015)

Preparation of Geopolymer Concrete Mixes

Preparation of geopolymer concrete is similar to that of cement concrete. Two

COARSE?
types of coarse aggregates, sand and fly ash were mixed in dry state. Then add THE

prepared mixture solution of sodium hydroxide and sodium silicate along with extra

water based on water-to-geopolymer binder ratio and mix thoroughly for 3–4 min so

as to give homogeneous mix.

It was found that the fresh fly ash based geopolymer concrete was viscous,

cohesive and dark in color. After making the homogeneous mix, workability of fresh

geopolymer concrete was measured by flow table apparatus as per IS 5512-1983

and IS 1727-1967. Concrete cubes of side 150 mm are casted in three layers. Each

layer is well compacted by tamping rod of diameter 16 mm. All cubes were place on

table vibrator and vibrated for 2 min for proper compaction of concrete. After

compaction of concrete, the top surface was leveled by using trowel.

24 HOURS
After 24 h of casting, all cubes were demolded and then placed in an oven for

thermal curing (heating). To avoid the sudden variation in temperature, the concrete

cubes were allowed to cool down up to room temperature in an oven. Three cubes
 17

were cast and tested for compressive strength for each curing period. (Subhash v.

Pantakar,2015)

Curing conditions

The temperature and curing time enhance mechanical strength, particularly

early age strength, improves durability, and limits product fluctuations and

efflorescence. Increasing the temperature during initial curing accelerates the

reaction rate of these materials. As in the case of Portland cement, higher

temperatures may have both beneficial and adverse effects on mechanical strength

development in geopolymer cements. The hydration products formed are generally

amorphous, although rising temperatures may on occasion lead to the formation of

BAWAL TO, PABUO AKO
crystalline products. NG MGA WORDS NA YAN

A curing temperature is the most important factor. As the curing temperature

increases, the setting time decreases, and compressive strength increases. The

curing temperature within 60 – 90 °C range, curing time in range of 24 h – 72 h and

compressive strength between SANA ALL40 – 50 MPa seem to be optimal. Mild curing
MAY SPACE

seems to improve physical properties while curing under higher humidity is not

usually beneficial. Rapid curing and/or curing at too high temperatures will result in

cracking and thus have a negative effect on physical properties. The current work

has therefore shown that the manufacture of a geopolymer product for specific

applications requires careful consideration of process conditions such as curing

temperature and humidity, in addition to the initial mix design.

Importance of Using Geopolymer Concrete IS THIS NAKABOLD

This type of concrete is starting to revolutionize concrete. It is being used more and

more in highway construction projects and offshore applications. It is still a little too

pricey for the do-it-yourself projects that abound, but contractors are starting to use it

more and more in other construction projects.

Advantages of Geopolymer Concrete

 18

1. High Strength – it has a high compressive strength that showed higher

compressive strength than that of ordinary concrete. It also has rapid strength

gain and cures very quickly, making it an excellent option for quick builds.

Geopolymer concrete has high tensile strength. It is less brittle than Portland

concrete and can withstand more movement. It is not completely earthquake

proof, but does withstand the earth moving better than traditional concrete.

2. Very Low Creep and Shrinkage – shrinkage can cause severe and even

dangerous cracks in the concrete from the drying and heating of the concrete

or even the evaporation of water from the concrete. Geopolymer concrete

does not hydrate; it is not as permeable and will not experience significant

shrinkage.

The creep of geopolymer concrete is very low. When speaking of creep in

concrete terms it means the tendency of the concrete to become permanently

deformed due to the constant forces being applied against it.

3. Resistant to Heat and Cold – It has the ability to stay stable even at

temperatures of more than 2200 degrees Fahrenheit. Excessive heat can

reduce the stability of concrete causing it to spall or have layers break off.

Geopolymer concrete does not experience spalling unless it reaches over

2200 degrees Fahrenheit.

As for cold temperatures, it is resistant to freezing. The pores are very small

but water can still enter cured concrete. When temperatures dip to below

freezing that water freezes and then expands this will cause cracks to form.

Geopolymer concrete will not freeze.

4. Chemical Resistance – it has a very strong chemical resistance. Acids, toxic

waste and salt water will not have an effect on geopolymer concrete.

Corrosion is not likely to occur with this concrete as it is with traditional

Portland concrete.
 19

Disadvantages of Geopolymer Concrete

While geopolymer concrete appears to be the super concrete to take the place of

traditional Portland concrete, there are some disadvantages such as:

1. Difficult to Create – geopolymer concrete requires special handling needs and

is extremely difficult to create. It requires the use of chemicals, such as

sodium hydroxide, that can be harmful to humans.

2. Pre-Mix Only – geopolymer concrete is sold only as a pre-cast or pre-mix

material due to the dangers associated with creating it.

3. Geopolymerization Process is Sensitive – this field of study has been proven

inconclusive and extremely volatile. Uniformity is

lacking.(civilengineersforum.com)
 20

METHODOLOGY

Conceptual Framework

•Alkaline Activating •Collection of Materials •Alkaline Solution mixed

Solution to be Used with water and Fly Ash
•Clean Water •Geopolymerization •Geopolymer Concrete
•Fine Aggregates •Producing of Specimen
•Coarse Aggregates •Curing (7, 14, 28)
•Testing of Samples
•Statistical Analysis

INPUT PROCESS OUTPUT

Flow Chart

GATHERING PREPARATION OF
SLUMP TEST
OF MATERIALS SPECIMEN

MOLDING OF CURING COMPRESSIVE

CONCRETE (7, 14, 28) STRENGTH TEST

STATISTICAL
ANALYSIS
 21

Data gathering
GATHERED
The data needed in this study were generated from the following:

1. Engineering books for general information about aggregates, cement, sand,

related topics;

2. Compilation of student thesis for information in proportioning, mixing and

testing of concrete; and

3. Internet for most recent findings that were related to the study, particularly

about the properties of coal fly ash.

Materials and apparatus

The following materials used in making concrete sample are fly ash, sodium

hydroxide and sodium silicate, water, gravel, and sand.

TOOLS
The following materials that were used for determining the unit weight of

coconut shell ash are metal volumetric measure, tamping rod, steel, 5/8 inches in

diameter, 24 inches long and balance and weights.

TOOLS
The following materials that were used for slump test are mixing board, slump

mold, metal ruler or meter stick, tamping rod, pointing trowel and container

The following materials and equipment that were used to determine the

compressive strength of the concrete samples are compression cylindrical mold, 6

inches in diameter, 12 inches in height, capping materials and facilities, curing

materials and facilities, pointing trowel, shovel container for mixing sample and

universal testing machine.

Proportioning of Geopolymer Cement

In this study, the researchers prepared three (3) different mixtures and
D
produce geopolymer cement.
 22

Table 1. Mixing proportions of fly ash and alkali activating solution

Treatment No. Fly Ash (%) Alkaline Activating

Solution(%)

1 73 27

2 67 33

3 61 39

Making Geopolymer Cement

For the development of fly ash based geopolymer concrete mix design

method, detailed investigations were carried out and following parameters were

selected on the basis of workability and compressive strength. In the investigation,

sodium based alkaline activators are used. The combination of sodium hydroxide

and sodium silicate are used for the activation of fly ash based geopolymer concrete.

Wet mixing method was used in mixing the fly ash and the activators. A
THIS IS BITIN
mixture with 70% fly ash and 30% activators. Alkali activator is composed of 30%

Sodium Hydroxide (12M) and 70% Sodium Silicate are combined. All proportions

were all based on mass. NAGULUHAN ATA AKO

SA SENTENCE CONSTR
Mixing concrete

Correct proportioning of the ingredients to produce concrete also provides a

balance between the requirements of economy, workability, strength, durability and

appearance.

The right proportioning of all the ingredients for concrete is the most difficult

manufacturing step to control, although it is one of the most important aspects in

producing high quality economical concrete.

In this study, the researchers conducted 3 sample specimens per curing days
CREATED
of geopolymer-based concrete with the same proportion and are placed in three
WERE
cylindrical molds. I MEAN, PAVERIFY SGURO NG THOUGHT NETONG PART NA TO.
 23

Procedure for Mixing Concrete

1. The working surface was cleaned off. The materials were also assured to be

clean.

2. Materials such as fly ash, sand and gravel are carefully weighed according to

their respective amount.

3. Sodium Hydroxide Flakes were prepared.

4. 12 M Sodium Hydroxide was mixed with distilled water.

5. A mixture with 30% Sodium Hydroxide solution and 70% Sodium Silicate

solution was produced as the binder.

6. Fly ash and alkaline activators were mixed according to its specified

proportion and produce geopolymer cement.

7. Sand was placed on the mixing surface together with geopolymer, mixed

them and achieves evenly distributed particles of each material.

8. With a shovel, a crater was made in the center of the heap.

9. Gravel was poured around the heap during the mixture by mixing to be evenly

and properly mixed together.

10. With a shovel, another crater was formed in the top of the heap.

11. As water was then added, a shovel was moved from the sides of the heap

into the central crater and turn part of the heap to distribute the water

throughout the mixture.

12. The materials were mixed within a minimum of almost fifteen minutes or even

for much longer period was done and assure that all ingredients were mixed

uniformly.

Slump Test

Slump of concrete was conducted pursuant to ASTM C143 or the standard

test method for slump of hydraulic-cement concrete. The slump test includes the

following procedures:

1. the slump test mold was damped and it were place on a flat, moist, non
 24

absorbent, rigid surface like a steel plate;

2. the mold was filled to 1/3 full by volume, and the bottom layer was tamped

again with 25 evenly spaced strokes;

3. the mold was filled again 2/3 full by volume (about 6 inches), ad was tamped

again with 25 strokes penetrating the top of the bottom layer;

4. the concrete was heaped on the top of the mold, and top layer was tamped

with 25 strokes penetration the top of the second layer;

5. the top surfaces of the concrete stroked off to the level of the mold;

6. the mold was carefully remove on a vertical direction; and

7. the mold was immediately place beside the slumped concrete and the rods

are

placed horizontally across the mold, and the slump was measured in

centimeters. The slump test took approximately 2 ½ minutes.

The degree of consistency of concrete could be ascertained by referring to Table 1.

Table 2. Recommended slumps for various construction structures

Types of construction Maximum Minimum
cm. cm.
Reinforced foundation wall and footing 13 5

Plain footing, caissons and sub – structure walls 10 2.5

Slab, beam and reinforced walls 15 7.5

Building columns 15 7.5

Pavements 7 5

Heavy mass construction 7 2.5

Source: Building Construction by Max Fajardo

Casting Cylinders

This test was carried out following the procedure of ASTM C31 or the standard

practice for making and curing concrete test specimens in the field. Test cylinders

were casted to verify the specified compressive strength of the mix has been

achieved. The procedures for casting cylinders are:

 25

1. the casting molds were places on the flat surface;

2. the inside surface of mold was coated with small amount of oil or petroleum

jelly;

3. the mold was filled to 1/3 full by volume and the bottom layer was tamped

with 25 strokes, evenly spaced;

4. the mold was filled again to 2/3 full, and the second layer was tamped with 25

strokes penetrating the top of the bottom layer;

5. the concrete was heaped on the top of the mold, and top layer was tamped

with 25 strokes penetrating the top of the second layers; and

6. the sides of the mold were tapped lightly to close the voids left by the rod;

7. the top surface of the concrete was stroked off using sawing action with the

rod until it smoothens. The cylinders were marked with the mixed number,

cylinder number, batch number, and date;

8. after 24 hours, the concrete was removed from the mold; and

9. the concrete was placed in a container filled with water for curing.

Curing of Concrete

Following the standard procedure of ASTM C31 or the standard practice for

making and curing concrete test specimens in the field, concrete cylinders were

cured at 7 days, 14 days and 28 days period. The procedure involves the following:

1. after removing the concrete from the mold, the concrete cylinders were

placed

inside a container filled with water;

2. the surface of the container was covered to avoid evaporation of water;

3. the concrete cylinders were allowed to absorb water until the specified date;

and

4. the researchers made sure that the concrete was undergone any disturbance.
 26

Compression Test

Cylinders tested for acceptance and quality control are made and cured in

accordance with procedures described for standard-cured specimens in ASTM C 31

standard practice for making and curing concrete test specimens in the field. An

average of 3 consecutive tests shall be done for each mix design. Compression test

involves the following procedures:

1. concrete specimens in its specified curing days were measured;

2. the diameter and length of the specimen was recorded;

3. test will be done at 7, 14, and 28 days period;

4. the specimens must be at least 12 hours free from the curing tank before the

weighing and compression test because a wet specimen can have a higher

weight;

5. both end of the specimen was ascertained perfectly leveled, if it‟s not then

both ends were capped with sulfur solutions;

6. the specimens were placed under the universal testing machine. Loads were

applied at a constant rate within the range of 20-50 psi per second. Loads

were

increased until specimen load failed;

7. the recorded load was divided by the cross sectional of the cylinder that gave

the ultimate compressive unit strength stress of the sample.

Cost Analysis

In this study, coal fly ash with alkali activator was used as a substitute to

cement and produced cement. The cost of producing geopolymer fly ash concrete

and ordinary Portland cement concrete were compared.

Experimental Results

Test results will be presented in tabulated and graphical form to be easily

understood. They will be shown in the appendices.

 27

Statistical Analysis

The experiment will be conducted using the Least Significant Difference

method (LSD) in Statistical Package for Social Sciences (SPSS). SPSS is a widely

used program for statistical analysis in social science. It is also used by market

researchers, health researchers, survey companies, government, education

researchers, marketing organizations, data miners, and others.

Analysis of Variance (ANOVA) will be used to analyze the data collected. The

results will be tabulated and interpreted.

 28

RESULTS AND DISCUSSION

This chapter shows the results of the study wherein fly ash and alkali

activators were utilized as cementitious binder in concrete. The researchers

conducted various tests to obtain data that is necessary for the research. The results

were showed through tabular and graphical form for better understanding. All data

were analyzed and evaluated to know the effects of the geopolymer binder as

replacement for ordinary Portland cement in the workability of the fresh concrete,

compressive strength of the hardened concrete.

Unit Weight of Materials

The researchers conducted loose and compact unit weight test for fly ash,

gravel and sand.

Table 3. Unit weight of materials

Materials Unit Weight (kg/m3)

Fly ash 1310

NAKABOLD PO LAHAT?
Sand 1570

Gravel 1522
Source: aqua-calc.com/substance/gravel-coma-and-blank-dry

Statistical Analysis

Randomized Complete Block Design (RCBD) is the one better fitted to use

upon testing the effectivity of the treatments (considering your data) than One-Way

ANOVA or Completely Randomized Design (CRD). For the reason that, the values of

the response variable were blocked according to Age Days from the molded date to

the testing date. Moreover, after testing the assumptions the results found

supplemented the claim hence, RCBD was used.

Experimental Design

Two factors, mixing ratio (m) and curing duration (c) were involve in the

experiment. A 3 x 3 factorial experimental design was used.

Treatments
 29

m1 – Fly Ash 73%; Alkali Activators 27%

m2 – Fly Ash 67%; Alkali Activators 33%

m3 – Fly Ash 61%; Alkali Activators 39%

c1 – 7 days curing

c2 – 14 days curing

c3 – 28 days curing

Treatment Combinations

T1 - m1c1 – 73% of fly ash and 27% of alkali activators was added and cured for 7

days

T2 - m1c2 - 73% of fly ash and 27% of alkali activators was added and cured for 14

days

T3 – m1c3 - 73% of fly ash and 27% of alkali activators was added and cured for 28

days

T4 – m2c1 – 67% of fly ash and 33% of alkali activators was added and cured for 7

days

T5 – m2c2 - 67% of fly ash and 33% of alkali activators was added and cured for 14

days

T6 - m2c3 - 67% of fly ash and 33% of alkali activators was added and cured for 28

days

T7 – m3c1 – 61% of fly ash and 39% of alkali activators was added and cured for 7

days

T8 – m3c2 - 61% of fly ash and 39% of alkali activators was added and cured for 14

days

T9 – m3c3 – 61% of fly ash and 39% of alkali activators was added and cured for 28

days
 30

Dependent Variable : Compressive Strength

Table 4. Tests of Between-Subjects Effects
Source Sum of DF Mean Square F P-VALUE Partial Eta

Squares Squared

Treatment 15455022.222 2 7727511.111 276.841 .000 962

Block 846288.889 2 423144.444 15.159 .000 579

Error 614088.889 22 27913.131

Total 78750200.000 26

The results on table 4 presented the rejection of the null hypothesis that the

treatments used have statistically equal compressive strength. The F computed is

found to be approximately 276.841 for the treatment, having 2 degrees of freedom.

As seen as well on the table, the p-value is 0.000 is less than 1 % level of

significance, which is considered highly significant. It implied that the treatments have

significant effects on the compressive strength. In other words, the different fly ash

and alkali activators contents have different compressive strength.

Even though the blocking variable (Age Days) is not the main focus, RCBD

also showed if its presence has significant value. The F computed is found to be

approximately 15.159 with having 2 degrees of freedom. The p-value is 0.000 which

is less than 1% level of significance, which is considered highly significant. It implies

that the different age days were not significantly different.

Effects of the effect size will add partial eta squared in our output. Partial eta

squared is 0.962 for treatment and 0.579 for block. That is the relative impact of

treatment is more than as strong as block. Last but not the least, adjusted r squared

tells us that 99.00% of the variance in compressive strength is attributable to

treatment and block. This is a high value, indicating very strong relationships

between our factors and compressive strength.

 31

Dependent Variable : Compressive Strength

Table 5. Multiple Comparisons

Turkey HSD

Treatment Treatment Mean Std. P- 95% Confidence

Difference Error value Interval
Lower Upper
Bound Bound
Fly Ash 67%:
- -
Alkali *
78.75861 .000 *
-804.3756
1002.2222 1200.0688
Fly Ash 73 %: Activators
Alkali 33%
Activators Fly Ash 61%:
* *
27% Alkali 848.8889 78.75861 .000 651.0423 1046.7355
Activators
39%
Fly Ash 73 %:
* *
Alkali 1002.2222 78.75861 .000 804.3756 1200.0688
Fly Ash 67%: Activators
Alkali 27%
Activators Fly Ash 61%:
* *
33% Alkali 1851.1111 78.75861 .000 1653.2645 2048.9577
Activators
39%
Fly Ash 73 %:
*
-
Alkali -848.8889 78.75861 .000 *
-651.0423
1046.7355
Fly Ash 61%: Activators
Alkali 27%
Activators Fly Ash 67%:
- - -
39% Alkali *
78.75861 .000 *
1851.1111 2048.9577 1653.2645
Activators
33%

Based on observed means.

The error term is Mean Square (Error) = 27913.131.

*. The mean difference is highly significant at the .01 level.

The treatment comparison was shown on table 2 using Tukey Honestly

Significant Difference (Tukey HSD). Tukey HSD is more conservative than the other

comparison test. In other words, more strict compare to Least Significant Difference
 32

(LSD) and maybe Duncan‟s as well. As of this part, each treatment mean is being

compared to each other for further identification of the better or more effective

treatment. Such that, a content of Fly Ash 73 %: Alkali Activators 27% was

being compared to Fly Ash 67%: Alkali Activators 33%. The content of Fly Ash 73 %:

Alkali Activators 27% was being compared to Fly Ash 67%: Alkali Activators 33%

was being compared to Fly Ash 61%: Alkali Activators 39%. Respectively, the mean

differences are found to be a whopping 1002.22 psi, and 848.88 psi with a standard

error of approximately 78. 758 psi. However, all of the comparisons in mean

differences have asterisk (**) which indicates that the difference is statistically

significant. The p-value of all the comparisons are approximately 0.000 are less than

1% level of significance, which is highly significant. This claim can be supported by

looking at the 95% confidence interval column wherein zero (0) is not observed within

the lower and upper bounds.

Table 6. Compressive Strength

Turkey HSDa,b

Subset
Treatment N
1 2 3
Fly Ash 61%:
Alkali Activators 9 613.3333
39%
Fly Ash 73 %:
Alkali Activators 9 1462.2222
27%
Fly Ash 67%:
Alkali Activators 9 2464.4444
33%
p-value 1.000 1.000 1.000

Means for groups in homogeneous subsets are displayed.

Based on observed means.
The error term is Mean Square(Error) = 27913.131.
a. Uses Harmonic Mean Sample Size = 9.000.
b. Alpha = .05.

Table 6 showed that the homogeneity is being tested among the treatments.

No fly ash contents and alkali activators or none of the treatments were observed to
 33

be homogenous because each treatment has different subset. All of the p-value

which is 1.000 is greater than 5% level of significance, failing to reject the null

hypothesis. In other words the means of the compressive strength for Fly Ash 73%:

Alkali Activators 27%, Fly Ash 67%: Alkali Activators 33% and Fly Ash 61%: Alkali

Activators 39% are 1462.22, 2464.44, and 613.33 respectively. It implied that they

are statistically different. Moreover, the empty space on table 3 indicated that the

mean compressive strength of that specific fly ash and alkali activators content is

significantly and statistically different from the other groups under a specific subset.

As shown in the table, the Fly Ash 67%: Alkali Activators 33% has the greatest

compressive strength means so it indicates that the best treatment among fly ash

and alkali activators content is Fly Ash 67%: Alkali Activators 33%.

Compressive Strength Test

Compression tests were done in Cavite Testing Center – Material Testing

Laboratory located at Km. 50 Aguinaldo Highway, Purok 4, Lalaan II, Silang, Cavite.
CARRIED? CHAR
Cylinders after the specified days of curing were delivered in the laboratory for

compression test. All concrete cylinders tested were released from the water 12
CUTE.
hours before the actual test assuming that the cylinders were completely dry.
 34

Figure 1. Profile Plots for Estimated Marginal Means of Compressive Strength

ESTIMATED MARGINAL MEANS COMPRESSIVE

STRENGTH
ANG PERFECT NG PAGKKAGAWA NETO
3,000.00 2,820.00
COMPRESSIVE STRENGTH (PSI)

2,490.00
2,500.00
2,083.33
2,000.00
1,606.67
1,546.67
1,500.00
1,233.33 7 days
14 days
1,000.00
753.33
28 days
520.00 566.67
500.00

-
FLY ASH 73%: ALKALI FLY ASH 67%: ALKALI FLY ASH 61%: ALKALI
ACTIVATORS 27% ACTIVATORS 33% ACTIVATORS 39%

TREATMENT

Figure 1 showed the profile plots for estimated marginal means of

compressive strengths. Figure 1 visualizes means for each combination of factors.

As shown in the figure, we see each line going down steeply between Fly Ash 67%:

Alkali Activators 33% and Fly Ash 61%: Alkali Activators 39%. Both treatment and

block seem to have a main effect compressive strength. The effect of treatment is

visualized as a line for each block separately. Since these lines look pretty similar,

the profile plot does not show much of an interaction effect.

Slump Test

It was observed that the slump test varies for the 3 mixtures. The factors that

affect the result were the physical condition of the materials. The shape and sizes of

gravel that were supplied by the hardware was not consistent and so it affects the

interaction of aggregate to the cement paste. Also the inconsistent force of tamping

of the slump was one of the factors that affect the results. Figure shows the graphical

result of the slump test of the mixtures. It is observed that the minimum design and
 35

maximum attain the minimum slump for concrete pavements while the average

design attains a lower slump which is a better result. It may also be affected by the

mix design since average design also shows a better compressive strength result.

Figure 2. Slump Concrete Diagram

GANDA NAMAN NG GRAPH
WHERE IS UR KAINIS
COMPARISON OF SLUMP S LUMP DI AG R AM
FOR GEOPOLYM
AND CONVENTIONAL 15.00
16.00 14.20
PCC?
SLUMP (CENTIMETERS)

14.00
12.00
9.00
10.00
8.00
Slump
6.00
4.00
2.00
-
FLY ASH 73%: FLY ASH 67%: FLY ASH 61%:
ALKALI ALKALI ALKALI
ACTIVATORS 27% ACTIVATORS 33% ACTIVATORS 39%

TREATMENT

Cost Analysis

Fly ash, crushed sand, gravel, sodium silicate and sodium hydroxide were

used in the production of concrete in this study. The unit cost of a 40-kg fly ash bag is

P140. Crushed sand has a unit price of P1175 per cubic meter. Gravel, on the other

hand, has a unit cost of P1000 per cubic meter. Same amount of these materials was

used in the treatments. Sodium silicate and sodium hydroxide which varied per

treatment were obtained for P88 per liter and P58 per kilogram, respectively.

Table 7. Cost production of concrete cylinders

MIX NO. TREATMENT PRODUCTION COST

1 Original P 209.86

2 Fly Ash 73 %: Alkali P 412.0782

Activators 27%
The table shows that the cost of production of cylinders of geopolymer

concrete is greater than the cost of production of cylinders of conventional Portland

cement concrete. The cost of geopolymer concrete is higher because of the

 36

presence of the alkaline activating solution but if geopolymer will be used for mass

production, the cost would be very much cheaper. The price of Sodium Hydroxide

could be as low as P7 per kilogram and the price of Sodium Silicate could range as

low as P675 up to P1100 per hundredweight. PER LITER UNG SODIUM SILICATE MO SA TAAS
 37

SUMMARY, CONCLUSION, AND RECOMMENDATIONS

Summary

The study entitled “Utilization Of Geopolymer Fly Ash As Concrete Binder “

was conducted at Biga II, Silang Cavite, Cavite Testing Center Laboratory and Cavite

State University-Main Campus. The main focus of the study was to determine the
ETO DAPAT MABABASA
SA STATEMENT ratio and proportion of fly ash to alkaline activators that would attain the highest
AT OBJECTIVE
OF THE STUDY.
compressive strength. The study also aimed to know the workability of fly ash and

alkaline activating solution as a replacement to cement as a binder in concrete

making, to determine the advantages and disadvantages of using geopolymer

concrete, the environmental impact, and to establish the compressive strength of

concrete from different proportions of fly ash and alkaline activating solution in 7, 14,

and 28 days curing periods.

There were three different mixes using fly ash and alkaline activating solution.

Quantity of materials was calculated using ratio and proportion. The needed

materials were gathered and prepared. Trial mixes were fly ash 61%: alkali activators

39% – fly ash 73 %: alkali activators 27% – fly ash 67%: alkali activators 33% and

was compared with a conventional concrete. Each mixture was replicated three

times. Concrete mix undergo slump test to check the workability of the treatments.

The test results showed that slump height varied with the ratio of fly ash and alkaline

activating solution being placed.

Concrete samples were cured for 7, 14, and 28 days and were subjected to

compression tests. The test results showed that the compressive strength found for

the three treatments for 7th days, 14th days, and 28th days curing period varies

depending on the workability of the mixture. The highest compressive strength was

attained with a mixture of 67% fly ash and 33% alkaline activator during its 28th day

with a mean compressive strength of 19.44 MPa or 2820 psi.

Geopolymer concrete has many advantages when compared to Portland

Cement Concrete; it is a newer product that is making traditional concrete look not so
 38

spectacular. Some of the top advantages of geopolymer concrete were its high

strength, very low creep and shrinkage, resistant to heat and cold, and chemical

resistance. It has a high compressive strength that showed higher compressive

strength than that of ordinary concrete. It also has rapid strength gain and cures very

quickly. Geopolymer concrete does not hydrate; it is not as permeable and will not

experience significant shrinkage. It has the ability to stay stable even at temperatures

of more than 2200 degrees Fahrenheit. Lastly, it has a very strong chemical

resistance. Acids, toxic waste and salt water will not have an effect of Geopolymer

concrete. Corrosion is not likely as it is with traditional Portland concrete.

While geopolymer concrete appears to be the super concrete to take the

place of traditional Portland concrete, there are some disadvantages such as: difficult

to create, used in pre-mix only, and geopolymerization process is sensitive.

Geopolymer concrete requires special handling needs and is extremely difficult to

create. It requires the use of chemicals, such as sodium hydroxide, than can be

harmful to humans. Geopolymer concrete is sold only as pre-cast or pre-mix material

due to the dangers associated with creating it. This field of study has been proven

inconclusive and extremely volatile. Uniformity is lacking.

 39

CONCLUSION

We can conclude from the test results showed that the Geopolymer Concrete

with the proportion of 73% Fly Ash: 27% Alkali Activators gained the highest strength.

The results of the study demonstrated that there is a significant relationship between

the proportions of the alkali activators and fly ash. During specimen preparation, it

was observed that maximum proportion (73% Fly Ash, 27% Alkali Activators)

produced a watery mixture due to higher content of Alkali activators but has the

lowest amount of fly ash. Minimum proportion (61% Fly Ash, 39% Alkali Activators)

has the highest content of fly ash and lowest amount of alkali activators, producing a

mixture of low consistency. From the three mixtures tested, the average proportion

(67%, 33%) develops the highest compressive strength. Maximum proportion ranks

second, then the minimum proportion in strength. It can be inferred from the result

that alkali activators, as a binding agent, works best with proper amount of fly ash.

Too much fly ash may not be mixed properly with the binder, and too much alkali

activator may just produce water-like mixture. Just like the conventional Portland

Cement Concrete wherein proper water cement ratio must be observed, right

proportion of fly ash and alkali activator must be made to attain the desired strength

of concrete.

COST EVAL PO.

 40

RECOMMENDATION

Since there is demand for natural sand, the fine aggregate shall be replaced

partially by quarry dust. Quarry dust is having high content of Silica, which may

increase the compressive strength of Geopolymer Concrete by partial

replacement of quarry dust. Different concentrations of Sodium Hydroxide

solution (8M, 10M, 12M, 14M & 16M) shall be used and the characteristics

shall be studied. Similarly the different curing methods shall also be studied. Hot air

curing, Steam curing, Sun curing and ambient curing shall be studied for the

above mentioned different Molar ratios of Sodium Hydroxide solutions. In order to

study the use of Geopolymer Concrete as of normal concrete, different structural

elements like Plain Cement Concrete Beam, Reinforced Cement Concrete

Beam, Reinforced Concrete Columns, Reinforced Beam Column joints shall be

cast for the above mentioned concentrations of Sodium Hydroxide solution and

curing conditions and tested. The characteristics of geopolymer concrete shall

be studied and based on the test results use of Geopolymer Concrete in

place of ordinary Portland cement concrete shall be recommended.