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Supplementary cementitious materials originfrom agricultural wastes A review

ARTICLE in CONSTRUCTION AND BUILDING MATERIALS JANUARY 2015

Impact Factor: 2.3 DOI: 10.1016/j.conbuildmat.2014.10.010

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Payam Shafigh


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Javad Nodeh Farahani


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Review

Supplementary cementitious materials origin from agricultural

wastes A review

Evi Aprianti a,, Payam Shafigh b, Syamsul Bahri b, Javad Nodeh Farahani b

a Department of Building Surveying, Faculty of Built Environment, University of Malaya, Malaysiab Department of Civil Engineering, Faculty of Engineering, University of Malaya, Malaysia

h i g h l i g h t s

Potential uses of agricultural wastes as cementitious material were reviewed.

Ashes from agricultural wastes have high silica content.

The use of RHA is limited due to the porosity nature of RHA particles.

POFA has good potential to be used as cementitious material in cement based materials.

a r t i c l e i n f o

Article history:

Received 25 July 2014

Accepted 8 October 2014

Keywords:

Supplementary cementitious material

PozzolansConcrete

Compressive strength

Agricultural waste

a b s t r a c t

Concrete is heavily used as a construction material in modern society. With the growth in urbanization

and industrialization, the demand for concrete is increasing day by-days. Therefore, raw materials and

natural resources are required in large quantities for concrete production worldwide. At the same time,

a considerable quantity of agricultural waste and other types of solid material disposal are posing serious

environmental issues. To minimize and reduce the negative impact of the concrete industry through the

explosive usage of rawmaterials, the use of agricultural wastes as supplementary cementitious materials,

the source of which are both reliable and suitable for alternative preventive solutions promotes the envi-

ronmental sustainability of the industry. This paper reviews the possible use of agricultural wastes as a

supplementary cementitious material in the production of concrete. It aims to exhibit the idea of utilizing

these wastes by elaborating upon their engineering, physical and chemical properties. This provides a

summary of the existing knowledge about the successful use of agricultural wastes such as rice husk

ash, palm oil fuel ash, sugar cane bagasse ash, wood waste ash, bamboo leaf ash, and corn cob ash in

the concrete industry.

2014 Elsevier Ltd. All rights reserved.

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

2. Supplementary cementitious material (SCM). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

2.1. Agricultural wastes as SCM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

2.1.1. Rice husk ash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

2.1.2. Palm oil fuel ash (POFA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

2.1.3. Bagasse ash (BA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

2.1.4. Wood waste ash. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

2.1.5. Bamboo Leaf ash (BLA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

2.1.6. Corn cob ash (CCA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

http://dx.doi.org/10.1016/j.conbuildmat.2014.10.010

0950-0618/ 2014 Elsevier Ltd. All rights reserved.

Corresponding author. Tel.: +60 1114247118; fax: +60 379675713.

E-mail addresses: [email protected], [email protected](E. Aprianti).

Construction and Building Materials 74 (2015) 176187

Contents lists available at ScienceDirect

Construction and Building Materials

j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c o n b u i l d m a t


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3. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

1. Introduction

Today, concrete has become the most commonly used building

material in the construction industry. The other important charac-

teristics of concrete, besides its strength, are its ability to be easily

moulded into any form, it is an engineered material that can

meet almost any desired specification, and it also adaptable,

incombustible, affordable and easily obtained. The great advantage

of concrete is its excellent mechanical and physical characteristics,

if properly designed and manufactured. Currently, concrete is

extensively used with more than 10 billion tons produced annually

in modern industrial society [1]. It has been estimated that by

2050, the rate of the worlds population will grow substantially

from 1.5 to 9 billion, and, thus, will cause an increase in the

demand for energy, housing, food and clothing as well as for con-

crete, which is forecast to increase to approximately 18 billion tonsannually by 2050[2].

Unfortunately, a considerable quantity of concrete is being pro-

duced, the effect of which is contrary to its benefits. In the last

100 years, the concrete industry has had an enormous effect on

the environmental appearances. In addition, CO2 emissions are

caused during the manufacturing process with a large volume of

raw materials required to produce the billions of tons of concrete

worldwide each year. The cement industry alone is estimated to

be responsible for about 7% of all the CO2 generated worldwide

[3]. It has been found that every ton of Portland cement produced

releases approximately one ton of CO2 into the atmosphere. In

addition, during the production of cement and concrete, issues like

carbon dioxide emissions, along with the use of energy and aggre-

gate consumption in great amounts, the demolition waste of con-

crete, and filler requirements, contribute to the common

environmental impact that concrete has making it a non-friendly

that is unsuitable for sustainable development.

Several studies have focused on finding alternatives that can be

used as replacement to cement, such as, the disposable and less

valuable wastes from industry and agriculture, whose potential

benefits can be realized through recycling, reuse and renewing

programmes. Hence, researchers have been investigating the effec-

tiveness, efficiency and availability of waste materials that are poz-

zolanic in nature as a cement replacement. The required materials

should be a by-product from an-original source that is rich in sili-

con (Si) and aluminium (Al). The framework for utilizing industrial

waste material for building applications has a successful history,

which includes fly ash, slag, and silica fume. Consequently, land

filled waste materials that are normally disposed of and land filled

are now deemed to be valuable for enhancing the desired proper-

ties of concrete.

Previous studies showed that some agro-waste materials could

be used as a cement replacement in cement based materials. The

utilization of agricultural waste can provide the break-through

needed to make the industry more environmentally friendly and

sustainable. The purpose of this paper is to clearly describe and

briefly introduce waste materials from agricultural commodities

that have been well managed and successfully used as supplemen-

tary cementitious materials (SCM) for the manufacture of concrete.

The relationships among concrete made using these types of waste

materials, environmentally friendly concrete, and green building

rating systems are also discussed. Mutual recognition of these

materials, and their usage in concrete by both civil engineers and

agricultural engineers, would pave the way for other potential uses

of solid waste materials in the construction industry, as well as cer-tain other industries. It will also lead to a more environmentally

sustainable concrete industry.

2. Supplementary cementitious material (SCM)

A substantial quantity of waste materials are produced globally

as by-products from different sectors, such as industrial, agricul-

tural, and wastes from rural and urban society. These waste mate-

rials, if not deposited safely, it may be hazardous. The type and

amount of sewage produced increases with the growth in popula-

tion. These wastes remain in the environment for a longer duration

since they are unused. The waste disposal crisis has arisen due to

the formation of decomposed waste materials. The solution to this

crisis lies in the recycling of wastes into useful products. Research

into the innovative uses of waste materials is continuously advanc-

ing. Waste and by-product materials, such as fly ash, silica fume,

ground granulated blast slag, rice husk ash, and palm oil fuel ash

have been successfully used in concrete for decades [48]. The suc-

cessful usage as a partial or whole replacement of Portland cement,

contributes to the resolution of the landfill problem and reduction

in the cost of building materials, provides a satisfactory solution to

the environmental issues and problems associated with waste

management, saves energy, and helps to protect the environment

from pollution. Agricultural wastes, such as rice husk ash, wheat

straw ash, and sugarcane bagasse ash, hazel nutshell ash which

constitute pozzolanic materials can be used as a replacement for

cement.

Today, supplementary cementing materials are widely used aspozzolanic materials (create extra strength by pozzolanic reaction)

in high-strength concrete, reduce permeability and improve the

durability of the concrete. Many types of pozzolans are used glob-

ally, and are commonly used as an addition or replacement for

Portland cement in concrete. It is well known that pozzolanic con-

crete contributes to the compressive strength in two ways: as the

filler effect and the pozzolanic reaction. Thus, the pozzolanic mate-

rial will reduce the demand or usage of cement at that time. A poz-

zolan comprises siliceous materials, and when combined with

calcium hydroxide, exhibits cementitious properties depending

on the constituents of the pozzolan. On the other hand, the high

early strength concrete can be produced by the highly reactive sil-

ica in pozzolans. The basis of the pozzolanic reaction is a simple

acid-based reaction between calcium hydroxide, also known asPortlandite (Ca(OH)2) and silicic acid (Si(OH)4). This reaction is rep-

resented as follows:

CaOH2

SiOH4

! Ca2 H2SiO24

2H2O

! CaH2SiO4 2H2O

And is the same as the abbreviated notation below:

CH SH! CSH~CSH

As the density of CSH is lower than that of Portlandite and pure

silica, a consequence of this reaction is a swelling of the reaction

products. This reaction, which is also known as alkalisilica reac-

tion may occur over time in concrete between the alkaline cement

pore water and poorly-crystalline silica aggregates.

E. Aprianti et al. / Construction and Building Materials 74 (2015) 176187 177
https://www.researchgate.net/publication/221997016_Optimum_mix_design_of_enhanced_permeable_concrete_-_An_experimental_investigation?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/221997016_Optimum_mix_design_of_enhanced_permeable_concrete_-_An_experimental_investigation?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/221997016_Optimum_mix_design_of_enhanced_permeable_concrete_-_An_experimental_investigation?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/258261876_Strength_and_Microstructure_of_alkali-activated_binary_blended_binder_containing_palm_oil_fuel_ash_and_ground_blast-furnace_slag?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==


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Basically, concrete is a combination of cement, water, fine and

coarse aggregate. As consequence of the greenhouse gas emissions

(GHG), most concrete mixtures utilize supplementary cementi-

tious materials (SCMs) either in blended cements or added sepa-

rately in the mixer. The utilization of SCMs, such as rice husk

ash, which is a by-product from agriculture, represents a viable

solution to the partial cement substitution. Which is divided into

natural and artificial materials. The usage of SCMs without the

additional process causes a significant decrease in CO2 emissions

per ton in the atmosphere. These materials are also referred to as

mineral admixtures or pozzolans, and when used in concrete and

combined with Portland cement form cementitious particles, how-

ever by themselves, they do not possess any cementitious com-

pounds. They should meet the requirements of the established

standards.

The structural advantage of SCMs is that they enable the pro-

ducer to modify the mixture and calculate the proper design of

the desired application. In addition, it can be used to improve the

performance of concrete, either in fresh or hardened mixtures. In

economic terms, using alternative waste materials can reduce the

cost of construction while providing comparable performance. This

cost includes the source and transportation of the alternative

material, controlled combustion process, and savings through

diversion, such as disposal management. Subsequently, the envi-

ronmental benefits will decrease the sizeable needs and demands

of Portland cement per unit volume of concrete as well as the

impact on the enormous deflation range of GHG emissions.

2.1. Agricultural wastes as SCM

Nowadays, global environmental warming is considered to be

the most important worldwide issue. Solid waste materials are

found everywhere, such as in the urban and rural society, industry

and agriculture. As agricultural wastes affect of the environment,

the use of these waste materials in construction will realize the

many benefits previously mentioned. Research has determined

that concrete that produced using agricultural wastes presentsimproved thermal properties [13,27,3649], which can result in

significant points being gained in the atmosphere and energy cat-

egory of Leadership in Energy and Environmental Design (LEED)

rating system. Moreover, due to the high cost constraints and lim-

ited availability of the main material in concrete, particularly in

developing countries, agricultural wastes used as SCMs in concrete

production can contribute to the environmental friendliness and

economic effectiveness of structures worldwide.

2.1.1. Rice husk ash

Rice husk is a natural sheath that forms around rice grains dur-

ing their growth. It is widely available in rice-producing countries,

and considered to be an agricultural solid waste material. Rice husk

has no commercial value when removed during the refining pro-cess. The rice milling industry is one of the most important sectors

in some countries, such as China, India, Indonesia, Malaysia and

Bangladesh, and worldwide by the end of 2013, the rice husk har-

vest produced approximately 742 million metric tons of rice pad-

dies annually [9]. Of this, more than 20% comprised the husk.

India produces around 160 million tons of rice husk (widely avail-

able waste) of which, during the milling process, about 78% of the

weight is rice, broken rice and bran, while the rest, 22% of the

weight of the paddy, is the husk [10]. Malaysia alone produces

approximately 3 million tons of rice paddies each year[9].Table 1

shows the top 10 highest countries that produced rice paddy in

2013[9]. Asia is still expected to sustain growth in the world rice

production in 2013.

The advantage of rice is that it produces a high volume of ricehusk, which is a low-density residue of the process [11]. At present,

the rice-producing countries are hindered by the landfill problem

of the rice husk, which they are attempting to utilize to benefit

the economy. When dumped, this waste covers a large area and

can self-incinerate, thereby spreading its ash over a wide area

and causing significant environmental problems. Unless used, this

large quantity of rice husk goes to waste and becomes a major

challenge to the environment by destroying the land and the areas

surrounding its dumping ground. A huge amount of RHA is pro-

duced globally and has been estimated to be growing at more than

7.5 million tons, or, approximately 1.1% each year[9].

2.1.1.1. Properties of rice husk ash (RHA). Rice husk ash (RHA) is a

carbon neutral green product gained from raw rice husk that is

changed to ash using the combustion process. The colour of the rice

husk ash (RHA) ranges from white grey to black, depending on the

source of the raw material, method of incineration, time and burn-

ing temperature. Many ways of disposal have been considered

including the commercial method of RHA. Rice husk is burnt in a

furnace/incinerator with a controlled laboratory atmosphere of

600800 C. After the firing process, the produced ash is cooled,

either rapidly or slowly. The rapid cooling method is performed

by uniformly distributing the ash in trays at a laboratory ambient

temperature of 21 1 C after reaching the required temperature

of 800 C. The slow cooling method involves, leaving the ash in

the incinerator. It can be used in large amounts to make special

supplementary concrete mixes. This RHA, in turn, contains around

8590% of amorphous silica[1315].

Zain et al.[15]reported a new method for producing RHA. The

rice husk, as displayed inFig. 1(a), is the raw form after the milling

process, which is fired in a gas furnace at a rate of 10 C per minute

up to 700 C, and maintained at this temperature for 6 h. Thereaf-

ter, it is left to cool at room temperature, as shown in Fig. 1(b).

There are various chemical compositions of rice husk ash due to

the type of paddy, differences in the type of land, harvest year,

combustion temperature, cooling method and geographical

conditions.

RHA is a very fine material. The average particle size of RHArangesfrom 5 to 10lm [14]. Table 2 shows the physical and chem-

ical properties of RHA, Portland cement and some cementitious

materials. RHA should meet the requirements of the chemical com-

position of pozzolan to be used in cement and concrete, as stated in

ASTM C618. The amount of silicon dioxide (SiO2), iron oxide

(Fe2O3) and aluminium oxide (A12O3) in the ash should not be less

than 70%, and the loss of ignition (LOI) must be up to 12%, as men-

tioned in the ASTM requirements. In addition, Chauhan and Kumar

[75]clearly explained the importance physical properties of mate-

rial used that control the flow of micro-system in concrete such as

surface area, fineness, incineration system and porosity.

Fig. 3 shows the SEM morphology of the RHA powder. As shown

in this figure, RHA grains are in different shapes and have porosity

on the surface. Thus causing the mixing water to be absorbed, andreducing the slump value and workability. In addition, Fig. 2 shows

that the cellular shape of rice husk ash gets broken due to the

longer period of the grinding process. After the grinding process

within 15, 60 and 120 min, the average diameter of the rice husk

ash particle was 49.0 lm (Fig. 2a), 41.0 lm (Fig. 2b) and 16.6 lm

(Fig. 2c), respectively. As described inFig. 2a, the cellular shape

of RHA could be clearly seen. The transformation occurs for

120 min (Fig. 2c), the cellular particles become smaller and disap-

pear. This observation determines that the RHA sample is com-

posed of irregular shaped particles with micro-pores, which

could significantly affect the properties of the final product.

Researchers [8,1316] agree that finer pozzolanic ash is better.

The fineness of the RHA is important because it influences the rate

of reaction and gains in concrete strength. The fineness also influ-ences the water-cement ratio, workability, shrinkage and creep of

178 E. Aprianti et al. / Construction and Building Materials 74 (2015) 176187
https://www.researchgate.net/publication/257388699_Reduction_in_environmental_problems_using_rice-husk_ash_in_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/257388699_Reduction_in_environmental_problems_using_rice-husk_ash_in_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259969543_Radon_resistant_potential_of_concrete_manufactured_using_Ordinary_Portland_Cement_blended_with_rice_husk_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/257388699_Reduction_in_environmental_problems_using_rice-husk_ash_in_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259969543_Radon_resistant_potential_of_concrete_manufactured_using_Ordinary_Portland_Cement_blended_with_rice_husk_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229303694_Thermal_insulators_made_with_rice_husk_ashes_Production_and_correlation_between_properties_and_microstructure?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==


5/13

concrete. Mahmud et al. [17] reported that finer RHA particles

yield a larger surface area and increase the strength of the con-crete. The very fine and chemically reactive substance would fill

the empty columns in the concrete in an optimum manner. Fig. 4

shows photos of the rice husk in raw conditions (4a) that was

obtained from a rice mill located in Kuala Selangor, Malaysia. The

RHA conditions before and after the grinding process are displayed

inFig. 4b and c, respectively.

2.1.1.2. Rice husk ash as pozzolan. Papadakis and Tsimas[19]con-

firmed that the sustainable development of the cement and con-

struction industries could be achieved by maximizing of the use

of the cementitious and pozzolanic by-products. According to

ASTM C 595[17], a pozzolan is defined as a siliceous or siliceous

and aluminous material, which in itself possesses little or no

cementitious value but will, in finely divided form and in the pres-ence of moisture, chemically react with calcium hydroxide to form

compounds possessing cementitious properties (pozzolanic activ-

ity). It can be explained that when pozzolanic materials are com-

bined with Portland cement, they will react to form cementitious

properties, whereas by themselves, they do not possess any

cementitious properties. Therefore, a cementitious material can

exhibit a self-cementitious (hydraulic) activity and contains quan-

tities of CaO while a pozzolanic materials requires Ca(OH)2to form

strength. It is generally accepted that the CaO content of the last

material is sufficient to react with all the pozzolanic compounds

and show pozzolanic activity (pozzolanic and cementitious materi-

als). Consequently, all these materials are often used in a mixture

with Portland cement which is essential for their activation,

Ca(OH)2from its hydration.The possible chemical reaction between silica and Ca(OH)2 in

the presence of water is as follows:

n SiO2 n CaOH2 H2O! n Cax SiOx n H2O 1

It was found that the secondary CSH gel was obtained from a

reaction between the silica (SiO2) and Ca(OH)2, as stipulated in the

chemical equilibrium above (Eq. (1)). According to Sugita et al.

[21], the formation of CSH gel in RHA-concrete was possibly

caused by the reaction between the SiO2 present in the RHA and

the Ca(OH)2 in the hydrating cement. They proposed that the C

SH gel was chemical structure of the Ca1.5SiO3.5xH2O.

In the combustion process, the matrix of celluloselignin from

the raw rice husk burns up and remains only as a porous silica skel-

eton. The RHA is considered as a good super-pozzolan material inthe production of concrete due to its high silica content. Thus,

the RHA contains a large volume of silica [12,19], and constitutes

a highly reactive pozzolanic material. The optimized and highlyreactive rice husk ash is found when it is incinerated under a con-

trolled temperature. The optimized RHA properties could be used

as a pozzolanic material in concrete. The duration and temperature

of the furnace are important parameters that influence the reactiv-

ity of the RHA pozzolans. The silica in the rice husk initially exists

in an amorphous form. However, it may become crystalline when

the rice husk is burnt at high temperature. In addition, the silica

in the RHA will not remain porous and amorphous when com-

busted for a long period at a lowtemperature (


6/13

pores and increases the probability of transforming the continuous

pores into discontinuous ones. Hence, all these mechanisms make

the microstructure of the paste more homogeneous and dense. The

performance of concrete with RHA as a supplementary cementi-

tious material (partially cement replacement) is outstanding con-

sidering its resistance to water [8,10] and chloride ion

penetration [24], which, in many cases, constitute the most impor-

tant characteristic for durability and the prevention of corrosion.

The highlighted properties that are the result of air permeability

and chloride ion penetration will show different behaviors depend-

ing on thew/cratio used in the mixtures. Moreover, the incorpora-

tion of RHA in concrete materials resolves the current problemsassociated with the disposal of RHA.

2.1.2. Palm oil fuel ash (POFA)

2.1.2.1. Origins of palm oil fuel ash (POFA). The oil palm is a tropical

palm tree, which is easily cultivated in tropical countries, such as

Malaysia, Indonesia, Thailand, Africa, and Latin America, 90% of

the palm oil production is generated by three of the ASEAN coun-

tries. Palm oil can be grown in many parts of the tropical world, but

is mainly productive within the equator line, which include Indo-

nesia, Malaysia, and several parts of Thailand. The high productiv-

ity of oil palm is concentrated in the tropical zone; located 10 to

the North or South of the equator.Fig. 5shows the worldwide pro-

duction of palm oil in 2009[10]. Malaysia produces 7 million tonsof crude palm oil each year [26], and Thailand produces 100,000

tons of palm oil fuel ash (POFA)annually [31], which is likely to

increase due to the development of palm tree plantations.

Palm trees are generally used in commercial agriculture. They

do not produce branches and are spread by sowing the seeds. It

comprises an oily, fleshy outer layer, with a single seed (kernel),

which is rich in oil [29]. Tangchirapat et al. [30]defined POFA as

an agro-waste ash from which palm oil residue, such as palm fibre

and shells, is burnt at temperatures of 8001000 C to produce

steam for the generation of electricity in biomass thermal power

plants. The typical oil palm residue constitutes15% shell and 85%

fibre. To produce energy, the empty fruit bunches are burned in a

boiler. Generally, it also produces about 5% ash by weight of solidwaste. The solid waste and ash material produced are rarely used,

thus, posing a serious ecological problem through the concomitant

pollution of the environment. Thus, it should present a feasible

solution to both the problem of land-filling as well as the high cost

of building materials and pollution of the planet. Basically, waste

disposal is always considered as a negative value due to the

costly practices. In addition, the manageable maximized use of

POFA will produce positive value products as well reduce the

environmental problems. Compared to other types of palm-oil

by-product, both the 20th and 21st century, POFA has represented

an environmental disruption pollutant that ends-up in the atmo-

sphere without being utilized.

2.1.2.2. Manufacture and properties of POFA. Palm oil fuel ash(POFA) is a waste product obtained in the form of ash through

Fig. 1. (a) Raw rice husk and (b) rice husk ash (RHA)[15].

Table 2

The chemical and physical properties of Portland cement and some cementitious materials [5,8,11,18,27,34,35,69,74,75].

Chemical composition (%) Ordinary Portland cement I Ordinary Portland cement II Rice husk ash (RHA) Palm oil fuel ash (POFA) Corn cob ash (CCA)

SiO2 20.422.0 21.9 80.795.9 59.666.9 65.467.3

Al2O3 3.75.3 4.9 0.40.4 2.56.4 6.09.1

Fe2O3 2.34.2 3.3 0.22.9 1.95.7 3.85.6

CaO 61.565.4 62.3 1.11.5 4.96.4 10.312.9

MgO 1.24.8 2.3 0.30.9 3.04.5 1.82.3

SO3 2.23.0 2.1 0.71.2 0.31.3 1.01.1

Na2O 0.10.2 1.2 0.91.2 0.20.8 0.40.5

K2O 0.31.1 0.3 0.82.1 5.07.5 4.25.7

LOI 0.42.3 1.1 2.86.6 6.610.0 0.91.5

Physical properties

Median particle size (lm) 5.010.0 10.5 29.045.0

Specific gravity 3.03.3 2.903.2 2.02.2 1.92.4 2.53.6

Blaine fineness (m2/kg) 336.5399.0 305.0 350.0376.8 493.0 270.0385.0

https://www.researchgate.net/publication/259518736_Agricultural_wastes_as_aggregate_in_concrete_mixtures_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259518736_Agricultural_wastes_as_aggregate_in_concrete_mixtures_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119413_Evaluation_of_the_sulfate_resistance_of_concrete_containing_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119413_Evaluation_of_the_sulfate_resistance_of_concrete_containing_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/234071493_Utilization_of_oil_palm_kernel_shell_as_lightweight_aggregate_in_concrete_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/234071493_Utilization_of_oil_palm_kernel_shell_as_lightweight_aggregate_in_concrete_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/237950135_Use_of_palm_oil_fuel_ash_as_a_supplementary_cementitious_material_for_producing_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229110564_Influence_of_pozzolan_from_various_by-product_materials_on_mechanical_properties_of_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229110564_Influence_of_pozzolan_from_various_by-product_materials_on_mechanical_properties_of_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/237950135_Use_of_palm_oil_fuel_ash_as_a_supplementary_cementitious_material_for_producing_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229110564_Influence_of_pozzolan_from_various_by-product_materials_on_mechanical_properties_of_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119413_Evaluation_of_the_sulfate_resistance_of_concrete_containing_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/257388699_Reduction_in_environmental_problems_using_rice-husk_ash_in_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/23766011_Quick_monitoring_of_pozzolanic_reactivity_of_waste_ashes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405519_Development_of_corn_cob_ash_blended_cement?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/234071493_Utilization_of_oil_palm_kernel_shell_as_lightweight_aggregate_in_concrete_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/261185044_The_Effect_of_Rice_Husk_Ash_on_Mechanical_Properties_and_Durability_of_Sustainable_Concretes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259969543_Radon_resistant_potential_of_concrete_manufactured_using_Ordinary_Portland_Cement_blended_with_rice_husk_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259518736_Agricultural_wastes_as_aggregate_in_concrete_mixtures_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==


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the burning of solid wastes, such as palm oil husk or fibre and palmkernel shell, as fuel in a palm oil mill boiler. Fig. 6a shows the res-

idue from the palm oil industry, and, after analysis using a 300lm

sieve, becomes ash, as presented inFig. 6b. The manufactured pro-

cess of POFA varies from the initial preparation to the incineration

process. Noorvand et al. [73] examined the initial preparation of

POFA after the combustion process by dried samples in an oven

at 105 5 C for 24 h. Tangchirapat et al. [30] prepared the ash

using the combustion process at a temperature of about 700

1000 C and sieve No. 16 (1.18 mm opening) to remove foreign

materials during the incineration process. They found three differ-

ent types of POFA based on specific gravity original size (OP), med-

ium size (MP) and small size (SP).The specific gravity was 1.89,

2.36, and 2.43 for OP, MP, and SP, respectively. It can be concluded

that the grinding process not only improves the fineness of POFA,but also the specific gravity. Another preparation method was

conducted by Abdul Awal and Shehu [36] in 2013, in which the

ash was obtained from the foot of the flue tower in Johor, the

southern-state of Malaysia. Thereafter, it was sieved through a

150lm filter and ground in a modified Los Angeles abrasion test

machine with 10 stainless steel bars (12 mm diameter and

800 mm long) instead of steel balls inside in order to increase

the fineness. The ash produced sometimes varied in colour, from

whitish grey to a darker shade, based on its carbon content

[30,31,33,34,7173]. At the end, it was noted that the raw materi-

als for POFA could come from the fuel industry, self-combustion in

a furnace or other milling industries. All the fine ash was trapped

while escaping from the burning chambers of the boiler, then

sieved through a 150300lm filter to remove the bigger sized

ash particles as well as any materials that had not been considered.

In other words, the physical characteristics of POFA are very much

influenced by the operating system in the palm oil factory. The ash

was ground in a Los Angeles abrasion test machine that contains

within it 1020 stainless steel bars instead of steel balls.

In bulk, POFA is greyish in colour and becomes darker as the

proportions of unburned carbon increase. The properties of POFA

are described in Table 22. The main oxide of POFA is silicon dioxide

or SiO2. It has been explained that POFA is moderately rich in silica

content (59.666.9%) compared to that of OPC. In addition, the

amount of iron content (1.95.7%) is similar to that of CaO, which

is very low, i.e. about 5%. However, it is much finer than OPC and its

specific gravity is around 1.92.4 as mentioned in Table 2. Further-

more, the combustion process influences the amount of carbon

present in the ash. For instance, Loss on Ignition (LOI) detected

8.25%, which is somewhat higher than the maximum value of

6.0% stipulated in ASTM C618 [37]. The difference in the amount

of the chemical components in POFA is due to the material source,

and burning process and efficiency (time and temperature).

2.1.2.3. Pozzolanic reaction of POFA. The formation of calciumsili-

catehydrate or CSH is gained from the reaction between SiO2and Al2O3in a pozzolanic material with Ca(OH)2in a cement paste.

The Ca(OH)2is used as an indicator in pozzolanic reaction. Chinda-prasirt et al.[72] reported that the increasing portion of the pozzo-

lanic replacement and fineness will cause a reduction in the

Ca(OH)2 content, while improving the sulphate resistance in con-

crete. They found that high fineness POFA has a faster pozzolanic

reaction than coarse POFA (without sieving). Hence, POFA can

improve the compressive strength of concrete due to its high fine-

ness which is denser and more homogeneous. In addition, the use

of POFA as a binder satisfies the chemical requirement in ASTM

C618 as a pozzolanic material by having a loss on ignition (LOI)

of less than 10%. Hence, it could be beneficial in the manufacture

of concrete. Many researchers [26,3032] have found solutions

for making use of this by-product to be a valuable waste. In

2011, Jaturapitakkul et al. [38] investigated the compressive

strength of mortar due to the pozzolanic reaction of POFA for1040% of cement replacement by weight of binder. The compres-

sive strength of mortar due to the pozzolanic reaction of POFA var-

ied from 0.1 MPa to 4.5 MPa at 7 days and 2.5 MPa to 22.5 MPa at

90 days. This result confirms that the pozzolanic reaction of POFA

is small at an early age and increases in significance at a later

age. It also shows that the pozzolanic reaction of POFA increases

with arising particle fineness, cement replacement rate and age

of concrete. Furthermore, POFA (median particle size of approxi-

mately 10lm) has been utilized in the production of HPC, in which

the highest compressive strength was found to be in the range 60

86 MPa, which was obtained at the POFA replacement level 20% at

28 days with a total binder 550560 kg/m3 [30,3334]. According

to Jaturapitakkul et al. [31], the increased fineness of POFA will

reduce the expansion and loss in the compressive strength of con-crete. They suggested that POFA could be used as a pozzolanic

Fig. 2. SEM of RHA particles ground for (a) 15 min grinding process, (b) 60 min

grinding process, (c) 120 min grinding process and (d) after sieving analysis[15].

https://www.researchgate.net/publication/259531309_Physical_and_chemical_characteristics_of_unground_palm_oil_fuel_ash_cement_mortars_with_nanosilica?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/237950135_Use_of_palm_oil_fuel_ash_as_a_supplementary_cementitious_material_for_producing_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/256712419_Evaluation_of_heat_of_hydration_of_concrete_containing_high_volume_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248541689_Effect_of_fly_ash_fineness_on_microstructure_of_blended_cement_paste?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251621578_Filler_effect_and_pozzolanic_reaction_of_ground_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119413_Evaluation_of_the_sulfate_resistance_of_concrete_containing_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119413_Evaluation_of_the_sulfate_resistance_of_concrete_containing_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/237950135_Use_of_palm_oil_fuel_ash_as_a_supplementary_cementitious_material_for_producing_high-strength_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248541689_Effect_of_fly_ash_fineness_on_microstructure_of_blended_cement_paste?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119413_Evaluation_of_the_sulfate_resistance_of_concrete_containing_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259531309_Physical_and_chemical_characteristics_of_unground_palm_oil_fuel_ash_cement_mortars_with_nanosilica?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/256712419_Evaluation_of_heat_of_hydration_of_concrete_containing_high_volume_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251621578_Filler_effect_and_pozzolanic_reaction_of_ground_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/232405564_Production_of_rice_husk_ash_for_use_in_concrete_as_a_supplementary_cementitious_material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==


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Fig. 3. SEM morphology of RHA particles in different scales.

Fig. 4. (a) Raw rice husk from Selangor, Malaysia (b) RHA before grinding and (c) RHA after grinding [20].

Table 3

Selected mix proportion of RHA concrete according to the compressive strength [8,13,16,26,27,70,71].

Mix No. Cement RHA (%) Super plasticizer (SP)% Water Aggregate 28-Day cube compressive strength (Mpa) Ref.

Fine Coarse

1 376 5 1.0 210 844 951 35.4 Madandoust et al.[71]

2 393 10 0.5 165 723 1018 40.0 Sensale et al.[14]

3 481 10 0.9 162 690 1050 47.8 Hesami et al.[8]

4 420 15 1.0 189 815 995 46.9 Ramezanianpour et al.[27]

5 550 15 1.1 162 710 180 53.0 Mahmud et al.[17]

6 1067 15 1.0 628 1,997 4283 50.0 Nagrale et al.[28]

7 889 15 1.1 628 2,176 4268 42.8 Nagrale et al.[28]

8 300 20 0.9 250 94 1456 33.5 Rahman et al.[70]

9 400 25 0.9 250 150 1400 42.9 Rahman et al.[70]

10 277 30 1.1 210 844 951 26.6 Madandoust et al.[71]

Unit = kg/m3.

https://www.researchgate.net/publication/251620811_High-strength_rice_husk_ash_concrete_incorporating_quarry_dust_as_a_partial_substitute_for_sand?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251620811_High-strength_rice_husk_ash_concrete_incorporating_quarry_dust_as_a_partial_substitute_for_sand?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/261185044_The_Effect_of_Rice_Husk_Ash_on_Mechanical_Properties_and_Durability_of_Sustainable_Concretes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/268200448_Utilization_Of_Rice_Husk_Ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/268200448_Utilization_Of_Rice_Husk_Ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/258212421_Self_compacting_concrete_from_uncontrolled_burning_of_rice_husk_and_blended_fine_aggregate?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/258212421_Self_compacting_concrete_from_uncontrolled_burning_of_rice_husk_and_blended_fine_aggregate?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251682241_Mechanical_properties_and_durability_assessment_of_rice_husk_ash_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248504692_Effect_of_rice-husk_ash_on_durability_of_cementitious_materials?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/248541091_Origin_of_the_pozzolanic_effect_of_rice_husks?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/268200448_Utilization_Of_Rice_Husk_Ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/268200448_Utilization_Of_Rice_Husk_Ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/251620811_High-strength_rice_husk_ash_concrete_incorporating_quarry_dust_as_a_partial_substitute_for_sand?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/258212421_Self_compacting_concrete_from_uncontrolled_burning_of_rice_husk_and_blended_fine_aggregate?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/258212421_Self_compacting_concrete_from_uncontrolled_burning_of_rice_husk_and_blended_fine_aggregate?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/258212421_Self_compacting_concrete_from_uncontrolled_burning_of_rice_husk_and_blended_fine_aggregate?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/261185044_The_Effect_of_Rice_Husk_Ash_on_Mechanical_Properties_and_Durability_of_Sustainable_Concretes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/261185044_The_Effect_of_Rice_Husk_Ash_on_Mechanical_Properties_and_Durability_of_Sustainable_Concretes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/259518736_Agricultural_wastes_as_aggregate_in_concrete_mixtures_-_A_review?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229303694_Thermal_insulators_made_with_rice_husk_ashes_Production_and_correlation_between_properties_and_microstructure?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==


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material as well as to improve the sulphate resistance of concrete.

Meanwhile, Sata et al.[33]studied the ability of POFA as a pozzo-

lan to improve the strength of concrete. All researchers attributed

the improvements in the behavior of the POFA concrete to the poz-

zolanic reaction through which the hydration products were

released.

The development of the compressive strength for selected mix-

tures is presented in Table 4. For concrete mixtures containing var-

ious proportions of POFA, the result shows that the compressive

strength is more than 55 MPa at 28 days. Concrete samples with

20% and 30% POFA show values of 59 and 61 MPa, respectively.

After 28-days, the compressive strengths of all concretes contain-

ing POFA were higher than the normal concrete, as mentioned in

Table 4. The use of 20% POFA resulted in a compressive strength

of as high as 70 MPa at 90-days. Two different POFA (CAPOFA

and ALPOFA) were collected from diverse palm oil industries. The

different mixtures shown in sample G(I) indicate that using addi-

tional fibre (steel) as a binder aggregate to produce a significant

compressive strength of 175 MPa at 28-days compared with no

fibre. Meanwhile, at the same POFA proportions of 10%, 20%, and

30%, but combined with 10% SF, it produced an extraordinary

strength of up to 93 MPa. Furthermore, POFA can be used as a

cement replacement up to 30% in producing high-strength con-

crete, and the compressive strength obtained is higher than con-

crete made from Portland cement. The inclusion of the ultrafine

POFA tends to reduce the water demand of the high-strength con-

crete[42].Overall, the results described and presented show that

POFA possesses great potential pozzolanic cementing materials

with possibly superior engineering properties in proper mixing

and curing systems. It could also lead to the greater utilization of

waste material from the agricultural side. Subsequently, by mini-

mizing the volume of waste, which is disposed of landfill, will pro-

tect the environment as well as reduce the emission of GAGs

(greenhouse gases CO2). Furthermore, the use of POFA contributes

to a sustainable industry and may contribute to a reduction in the

construction-cost.

2.1.3. Bagasse ash (BA)

Fig. 7is the flow chart describing the production process from

sugar cane to raw sugar and the resulting by-product materials

as well as referring to the sugar extraction process. The by-prod-

ucts generated from the cogeneration and combustion process at

certain temperatures of sugar cane bagasse, which is called bagasse

ash (BA). Huge quantities of bagasse ash are being produced annu-

ally in developing countries, such as India, Thailand, Brazil, Paki-

stan, Columbia, the Philippines, Indonesia and Malaysia [4850],

and are going to be destroyed and disposed of into the environ-

ment. It has been concluded that this mineral is a promising poz-

zolanic material and can be successfully used as a supplementary

material in Portland cement in either the mortar or the concrete.

For instance, Cordeiro et.al[51]reported that by wt% of BA signif-

icantly decreased the maximum adiabatic temperature rise of con-

ventional concrete. In addition, the sugar cane bagasse ash

produced with air calcinations at 600 C and a rate of heating of

10 C/min presents amorphous silica, high surface area and low

carbon content[52].Similarly, a concrete mixture using BA would

not only reduce CO2 emissions worldwide but also increase the

market value of waste materials [4850,53]. The chemical and

physical properties of bagasse ash (BA) are the main factors affect-

ing the presence of pozzolan minerals. Table 5 explains the proper-

ties of BA from previous studies. The LOI of bagasse ash is more

than 10% based on the co-generation process and carbon content

within it. However, Chusilp et al. [57]determined that a high LOI

of bagasse ash had no prejudicial effect on the properties of the

binder, nonetheless, if the LOI is less than 10%, it will provide an

excellent pozzolanic material.

Few studies have been conducted on the use of bagasse ash to

produce a great result in the physical and mechanical properties

of concrete. In 2007, Ganesan et al. [56]used BA proportion in 5%

to 30 wt% OPC replacement in dry conditions. In their study, the

mill fired BA burnt under controlled conditions at 650 C for 1 h.

The control mix (1:3:3 cement:water:aggregate) was prepared

Fig. 5. World palm oil production in 2009[10].

Fig. 6. (a) Palm oil residue and (b) palm oil fuel ash [33].

https://www.researchgate.net/publication/245308058_Utilization_of_Palm_Oil_Fuel_Ash_in_High-Strength_Concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/273426234_Development_of_green_ultra-high_performance_fiber_reinforced_concrete_containing_ultrafine_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/273426234_Development_of_green_ultra-high_performance_fiber_reinforced_concrete_containing_ultrafine_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/257086437_Strength_and_heat_evolution_of_concretes_containing_bagasse_ash_from_thermal_power_plants_in_sugar_industry?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/257086437_Strength_and_heat_evolution_of_concretes_containing_bagasse_ash_from_thermal_power_plants_in_sugar_industry?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/237842694_Experimental_characterization_of_binary_and_ternary_blended-cement_concretes_containing_ultrafine_residual_rice_husk_and_sugar_cane_bagasse_ashes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229294028_Effect_of_calcination_temperature_on_the_pozzolanic_activity_of_sugar_cane_bagasse_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229294028_Effect_of_calcination_temperature_on_the_pozzolanic_activity_of_sugar_cane_bagasse_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119409_Effects_of_LOI_of_ground_bagasse_ash_on_the_compressive_strength_and_sulfate_resistance_of_mortars?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229373705_Evaluation_of_Bagasse_Ash_as_Supplementary_Cementitious_Material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/245308058_Utilization_of_Palm_Oil_Fuel_Ash_in_High-Strength_Concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/245308058_Utilization_of_Palm_Oil_Fuel_Ash_in_High-Strength_Concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/237842694_Experimental_characterization_of_binary_and_ternary_blended-cement_concretes_containing_ultrafine_residual_rice_husk_and_sugar_cane_bagasse_ashes?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/257086437_Strength_and_heat_evolution_of_concretes_containing_bagasse_ash_from_thermal_power_plants_in_sugar_industry?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229294028_Effect_of_calcination_temperature_on_the_pozzolanic_activity_of_sugar_cane_bagasse_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119409_Effects_of_LOI_of_ground_bagasse_ash_on_the_compressive_strength_and_sulfate_resistance_of_mortars?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229119406_Utilization_of_bagasse_ash_as_a_pozzolanic_material_in_concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/245308058_Utilization_of_Palm_Oil_Fuel_Ash_in_High-Strength_Concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/245308058_Utilization_of_Palm_Oil_Fuel_Ash_in_High-Strength_Concrete?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/273426234_Development_of_green_ultra-high_performance_fiber_reinforced_concrete_containing_ultrafine_palm_oil_fuel_ash?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==https://www.researchgate.net/publication/229373705_Evaluation_of_Bagasse_Ash_as_Supplementary_Cementitious_Material?el=1_x_8&enrichId=rgreq-82eb734e-e136-4353-9102-ee6fca0f2c1f&enrichSource=Y292ZXJQYWdlOzI2ODA4MDA5NDtBUzoyMjE4MDkwODY2MDMyNjRAMTQyOTg5NDgxNTIzNw==


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with a water binder ratio of 0.53 for 100 mm100 mm100 mm

cube specimens. The compressive strength optimum was obtained

from 20 wt% OPC replacement for 28 days and 90 days. They dem-

onstratedthat thereasons for theearlystrengthdevelopment of the

concrete containing bagasse ash are because of the fineness of the

particles, as well as the degree of BA reactivity and silica content.

The splitting tensile strength values after 28 days of curing for con-

cretes containing BA up to 20%increased to 4.81 MPa and at 2530%

of BA, thevalues decreased to 3 MPa. Rukzon and Chindaprasirt [50]

reported that the fine bagasse ash indicated that the concrete con-

taining BA up to 30% exhibited a compressive strength result of

68.6 MPa at 28 days. They concluded that the BA particle is finer

than OPC, therefore, it has an increase in the water uptake, and, of

course a larger surface area to react as well as to enhance the initial

and final setting time. The hardening process accelerated due to its

high silica and alumina content.

2.1.4. Wood waste ash

Nowadays, more than 70% of the wood waste is disposed of into

the environment in various forms [59]. The combustion process of

several wood products, such as chips and bark, produces a residue

called wood waste ash (WWA) or wood ash (WA). In general, WA

applications are limited to certain maintained levels for the

intended crop growth. However, the final process of WA should

be properly controlled due to the fineness of the particles and eas-

iness of air pollution that will cause respiratory problems to people

who live near the pollutant site. Research [58,60,61]has been con-

ducted to study the production of greener concrete material

incorporated with WWA as a replacement of cement as well as

for sustainability. Ramos et al. [60]investigated the compressive

and flexural strengths of the paste mix with 0%, 10%, and 40%

cement replacement with WWA and a W/C ratio of 0.4 at 7, 28,

90 and 180 days. They found the optimum compressive and flex-

ural strengths obtained for 10 wt% of WWA. For instance,

42 MPa, 52 MPa, and 61 MPa are the compressive strength for 7,

28 and 90 days, respectively. In accordance with the carbonation

process, cement mixtures using WWA shown a carbonation depth

greater than the mixture for Portland cement. WWA can be a

promising pozzolanic material for cement replacement and while

contributing to the sustainability of eco-constructions.

2.1.5. Bamboo Leaf ash (BLA)

In recent years, research has focused on the utilization of agri-cultural waste as a pozzolan in the manufacture of concrete. In fact,

the addition of ash from the agricultural waste combustion process

to concrete exhibits better properties and is eco-friendly. The bam-

boo leaf is one of the solid wastes derived from agriculture. Bam-

boo is the highest yielding natural resource and has the fastest

growth and can be used as fibre and other significant purposes

for construction materials.Fig. 8b shows the ash from the bamboo

leaf after the calcination process at 600 C for 2 h in an electric fur-

nace. The appearance of a bamboo leaf is presented in Fig. 8a.

This waste material is relatively new in the construction indus-

try and only a few studies have been conducted on the use of the

bamboo leaf ash in a concrete mixture. Dwivedi et al. [63] and

Singh et al.[64]investigated the hydration process of the bamboo

Table 4

The selected mix proportion of high strength concrete [30,34,36,4143].

No Mix proportion (kg/m3) W/c Slump (mm) Compressive strength (MPa) Ref.

Cement POFA Sand Coarse aggregate Water SP (l)

kg/m3 % 28 days 90 days

1 495.0 55.0 10 753 959 176 6.8 0.32 250 60 68 [30]

2 440.0 110.0 20 745 950 176 8.6 0.32 240 61 70

3 385.0 165.0 30 738 940 176 11.6 0.32 250 59 664 400.0 100.0 20 711 1067 145 11.5 0.28 37 52 [41]

5 400.0 100.0 20 711 1067 145 11.5 0.28 49 53

6 540.4 145.3 25 1057 1340 168 50.4 0.23 169 175 182 [42]

7 214.0 213.0 50 787 961 205 - 0.29 115 41 [36]

8 171.0 256.0 60 787 961 205 - 0.29 90 36

9 128.0 299.0 70 787 961 205 - 0.29 80 28

10 504.0 56.0 10 757 971 153 8.5 0.28 200 89 91 [34]

11 448.0 112.0 20 749 962 151 11.8 0.28 185 94 93

12 392.0 168.0 30 742 952 148 16.9 0.28 185 87 91

13 270.0 30.0 10 804 1024 216 0.72 80 39 40 [43]

14 240.0 60.0 20 801 1021 210 0.70 60 32 39

15 210.0 90.0 30 799 1018 219 0.73 75 28 34

SUGAR

INDUSTRY

SUGAR CANE

MILLING PROCESS RAW SUGAR

BAGASSECOGENERATION/

COMBUSTION

PROCESS

BAGASSE ASH

Fig. 7. The production process of by-product from sugar industry.

Table 5

The chemical and physical properties of bagasse ash (BA) [49,5256].

Chemical composition (% by mass)

SiO2 60.065.3

Al2O3 4.79.1

Fe2O3 3.15.5

MgO 1.12.9

CaO 4.010.5

Na2O 0.30.9

K2O 1.42.0

SO3 0.10.2

Physical properties

Particle size distribution, (lm) 66.9107.9

Specific gravity 1.92.4

Specific surface area (cm2/g) 274.0943.0

Loss on ignition (% by mass) 15.319.6

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