Using rice husk ash for production of bricks

Utilization and effect of using rice husk ash for production of bricks

Abhipsa Guru ?,Professor Mohibullah ?

Department of Civi lEngineering ,KIIT Deemed to be University,KIIT

Road,Patia,Bhubaneswar 751024

Department of Civil Engineering,KIIT Deemed to be University,KIIT

Road,Patia,Bhubaneswar 751024,[email protected]

Keywords: Rice husk ash ,Bricks ,Compressive strength ,flexural strength,durability

Abstract: There is increasing demand for producing durable construction

material.Rice husk ash(RHA) is aby product formed due to burning of rice husk.


to its high pozzolanic action the strength and durability of concrete is increased.The

main advantage of using rice husk ash is when itis added to concrete itincreases the

corrosion resistance.It also acts as agood insulator.The main objective of this article

is to investigate the feasibility of using rice husk ash in the production of bricks and

the effect of rice husk ash(RHA) content on the various properties of bricks such as

compressive strength,flexural strength,water absorption,bulk density etc.

The varying

percentage of rice husk ash(RHA) is used for studying the properties of bricks and

also analyzing the test results using rice husk ash(RHA).The utilization of rice husk

ash for production of bricks is not only cost effective but also addresses the need for

finding ways to reduce the amount of solid waste material.The investigation also

demonstrates afeasible way of using rice husk ash(RHA) as aconstituent for

producing decent quality of bricks.Increasing the rice husk ash(RHA) replacement

level decreases the strength and bulk density and increases the water absorption.

Get quality help now

Proficient in: Calcium Carbonate

4.9 (247)

“ Rhizman is absolutely amazing at what he does . I highly recommend him if you need an assignment done ”

+84 relevant experts are online
Hire writer


main motive of using rice husk ash(RHA) is producing bricks of decent quality.


Brick is one of the most widely used construction material in India.Bricks are made of

inorganic non-metallic material and are widely used as building component all over

the world.Bricks are considered as one of the strongest and long lasting building

materials available locally.Ordinary bricks are made of amixture of clay,which is

subjected to various processes and is differing according to the nature of material,the

method of manufacture.After itis properly prepared the clay is formed in moulds to

get the desired shape,then dried and burnt.One of the major drawback

of these conventional bricks is the environmental impact involved in the

manufacturing process.In this project,the effects of adding rice husk ash for the

production of bricks is studied.The risk husk ash is added in varying percentages,and

the effect ithas on the compressive strength,flexural strength,water absorption

investigated.There is aneed for reducing the impact of clay brick manufacturing

process on the environment and at the same time to increase the overall performance

of the brick so an alternative way is to be found out.Here,in this research the motive is

to achieve the above mentioned improvements by using the admixture for the

manufacturing process of bricks.The admixtures are added so that the bond between

the particles is increased which in turn increases the strength of the brick.The

admixtures are cementious or pozzolanic materials.The pozzolanic materials include

the traditional lime.The another type of admixture include rice husk ash,saw dust,coal

etc.which burn out when the bricks undergo firing.The advantages of adding the

admixtures are as follows:

1. As the organic admixtures like saw dust,rice husk ash etc.burn out the pores are

left behind in the product.Due to this itallows the control of the bulk density of the

brick products and as aresult helps in producing light weight and porous bricks.

2. The fuel and power expenditure involved in the brick manufacturing process is


3. The admixtures when added increases the strength of the brick.


2.1 Rice husk ash:Rice husk ash(RHA) is aby product obtained by burning rice

husk.The burning conditions greatly affects the properties of rice husk ash(RHA).The

composition of rice husk ash(RHA) is 40% cellulose,30% lignin and 25-30% hydrated

silica available in non crystalline form.Rice husk ash(RHA) is agood super

pozzolanic material.Due to its high pozzolanic action the strength and durability of

concrete is increased.The rice husk ash can be used as an admixture in concrete if the

rice husk is burnt in aspecific manner.When rice husks are burnt at 500-700 °C and

kept for short time,the optimum properties of rice husk ash can be obtained.The main

motive of using rice husk ash(RHA) is producing bricks of decent quality and also the

effect itshows on the properties of bricks.The rice husk ash shows pozzolanic action

which is helpful in improving the strength.

2.2 Clay:For the brick manufacturing process clay is used.The clay used should have

the following properties:

i. Clay becomes plastic when itcombines with water

ii. The clay used should have sufficient tensile strength to keep the particles together

The clay is composed of silica and aluminium compounds.The clays are of two

types.They are calcareous and non calcareous clays.The calcareous clays are

composed of calcium carbonate and when burns changes to yellow or cream

colour.Non-calcareous clay consists of feldspar and iron oxides,and when itis burnt

changes to brown,pink or red,depending on the quantity of iron oxide. The presence

of silica in the clay when itis heated at 900-1200 °C will change into glassy state.This

process is called vitrification in which the clay will change into crystalline

structure.The process of vitrification takes place so that the bricks achieve sufficient

strength.It needs approximately 3cubic metres of clay soil to prepare 1000 bricks.


A brick is said to be good brick clay when pure clay and sand mixture is mixed with

water in such amanner that itcan easily be moulded and dried without cracking.Here

the manufacturing of rice husk ash is to be investigated.Silica is considered as main

constituent of the brick earth which contains in clay either as free or combined

constituent.The silica that exists as the main constituent prevents the brick from

shrinkage,cracking and hardness.In RHA ahigher amount of silica is present so that it

will lower the weight of the brick.Here the rice husk ash(RHA) has been collected

from the rice milling boiler and the rice husk is utilised as fuel for boiling paddy.After

the collection of the rice husk ash(RHA) they have been properly grinded in the

laboratory.After grinding,harmful element has been removed from rice husk


Table 1. Composition of clay and rice husk ash(RHA):[3]

The experimental program consists of two parts:

1) Partial replacement of clay by RHA:Here the rice husk ash(RHA) is combined

with clay in various percentages ranging from 10-80% and the fundamental

properties of bricks like compressive strength,water absorption etc.are examined.

2) Full replacement of clay by waste material from various industries like RHA,lime

and gypsum.

In this work,the waste products are used in the building construction to see the impact

on the economy of the building construction as well.Here the rice husk ash is

collected from four different places.

Measuring RHA by volume of brick clay:

The total volume of brick clay is taken.The rice husk ash(RHA) has been mixed with

brick clay in various percentage by volume.

Preparation of Brick clay:

After the evaluation of the various volumes of rice husk ash(RHA) for the various

treatments,the RHA has been combined with brick clay in the field.The thorough

moulding of brick clay has been done on the ground.

Drying of brick:

It is essential to dry the bricks prior to burning,so that they are adequately hard

enough to be handled and also kept in the burning kiln without any injury.The drying

of moulded bricks were done by resting them on their edges for sometime and then

heaped in open order in long row and stacks.

Burning of bricks:

The bricks are burnt so that the hardness and strength is achieved.The burning of

bricks also increases the density.These bricks that are experimented have been burned

in clamps where the temperature is very high and itis increased to about 2100 °F.



The specific gravity test for all the materials were conducted utilizing the pycnometer

for all the samples passing through 4.75mm IS sieve.




The compressive strength of the samples prepared was evaluated using compression

testing machine.In order to get good results for this research three samples of each

composition were experimented and the average of the result is found out and also it

is tabulated.

Table no.2 Compressive strength test results[4]

Sl No. Material Specific gravity

1 Rice husk ash 0.45

2 Clay 2.25

Sl No. Type of sample Avg compressive


1 100% clay 4.938

2 95% clay + 5% Rice husk



3 90% clay + 10% Rice husk



4 85% clay + 15% Rice husk



5 80% clay + 20% Rice husk



6 75% clay + 25% Rice husk



Fig 1. Compressive strength of Rice husk ash brick[4]

5.2 Water absorption test:

The water absorption test of brick is stated as the weight of water,indicated as a

percentage of the dry weight,which is adopted by agiven method.A 24 hour cold

water immersion test was performed so that the water absorption test of the samples is

produced.In order to get good results 6samples of each composition were

experimented and the average of the results is tabulated.

Table No.3 Water absorption test results[6]

Sl No. Type of sample Water absorption(%)

1 100% clay 4.75

2 5% clay +95% rice husk ash 8.16

3 10% clay + 90% rice husk



4 15% clay + 85% rice husk



5 20% clay + 80% rice husk



6 25% clay + 75% rice husk



Fig 2Water absorption of Rice husk ash bricks[6]

5.3 Bulk Density Test:

The determination of bulk density of the samples were done by taking into account

the dry weight and the gross volume of all the six samples to get good results.The

average of these results are tabulated.

Table No.3 Bulk density test results[5]

Sl No. Type of sample Bulk Density

(Kg per cubic metre)

1 100% clay 1828.707

2 95% clay +5% rice husk ash 1811.157

3 90% clay + 10% rice husk



4 85% clay + 15% rice husk



5 80% clay + 20% rice husk



6 75% clay + 25% rice husk



Fig 3Bulk density of Rice husk ash bricks[5]


The following conclusions were drawn from the experimental results that we got are

as follows:

1) The clay burnt bricks were prepared with rice husk ash and these bricks showed

similar appearance in comparison to conventional clay bricks.

2) The bricks where rice husk ash is utilised as admixture shows that the bricks

experience higher percentage of water absorption in comparison to conventional

clay bricks.

3) The bricks with rice husk ash as admixture experienced aslight increase in

compressive strength with varying percentages of admixture.

4) The bricks where rice husk ash is used as admixture can be made of different

shapes or sizes so that they are useful in building construction.

5) The RHA bricks are prepared easily because the manufacturing process is simple

and also the machinery needed here is easily available.

6) The RHA bricks are also considered economical so they can be utilised in

building construction.

7) The density of the rice husk ash(RHA) bricks decreases with higher percentages

of rice husk ash(RHA).


[1] Mohan NV, Satyanarayana PVV, Rao KS. “Performance of rice husk ash bricks. ”

Int JEng Res Appl 2012;2(5):1906 –10.

[2] Akshay Satish More*, Ahad Tarade*, Ashwani Anant* “Assessment of suitability

of Rice husk ash burnt clay bricks ”,International Journal of Scientific and Research

Publications, Volume 4, Issue 7, July 2014 .

[3] Rafid Shams Huq1, Farhana Chowdhury2 “Use of Rice husk ash as substitute to

make clay bricks ”,International Journal of Innovative Research in

Science, Engineering and Technology, Vol. 7,Issue 10 ,October 2018 .

[4] J. Sutas*, A. Mana, L. Pitak “Effect of Rice husk ash to properties of

bricks ”,Procedia Engineering 32 (2012) 1061 –1067 .

[5] S.Raut, R.Ralegaonkar ,S.Mandavgane “Utilization of rice husk ash in production

of light weight bricks ”,journal of civil and mechanical engineering (2013 )269-275.

[6] Chao-Lung Hwang, Trong-Phuoc Huynh “Investigation into the use of rice husk

ash to produce eco-friendly construction bricks ”,Construction and Building Materials

93 (2015) 335 –341 .

[7] G. W. Carter, A. M. Cannor †and D. S. Mansel l.“Properties of bricks

incorporating rice husk ash ”,JBuilding and Environment ,1982 ;17 :285-291 .

[8] Kartini K., “Rice Husk Ash -Pozzolanic Material for Sustainability ”,International

Journal of Applied Science and Technology, 2011, 1(6), p.


[9] Tonnayopas D., Tekasakul P., Jaritgnam S., “Effect of rice husk ash on

characteristics of brick ”,Technology and Innovation for Sustainable

Development Conference, KhonKaen Univ. 28-29 Jan. 2008, Thailand, p. 36-39.

[10] Ashish Kumar Parashar and Rinku Parashar (2012), “Comparative Study of

Compressive Strength of Bricks Made W ith Rice husk ash to clay

Bricks ”,International Journal of Scientific and Research Publications, Volume 2,

Issue 7.

Cite this page

Using rice husk ash for production of bricks. (2019, Dec 14). Retrieved from

Let’s chat?  We're online 24/7