Cellular Lightweight Concrete is also known as CLC. In other words, CLC is also known as foamed concrete. The CLC is widely used for construction purposes as it has various advantages and usage than the traditional concrete bricks. The foamed concrete is manufactured from mixing of Portland cement, sand, fly ash, water and performed foam in varied proportions. This CLC (Cellular Lightweight Concrete) can be produced at building sites with the use of machines and molds used for normal concrete. One of an important characteristic of foamed concrete is it has self-compacting property as there is no compaction is required. And also, it easily flows out from the pump to fill the mold. With this property is can be pumped to maximum distance and height. For continuous cellular lightweight concrete is manufactured by mixing light mortar and preformed foam under pressure in a special static mixer.

1. CELLULAR CONCRTE
By
SHREEHARI KULKARNI
SG21SEC017
GUIDE: ARUNKUMAR B
SHARNBASVA UNIVERSITY KALBURGI

2. CONTENTS
• Introduction
• Literature review
• Objective
• Materials required
• Methodology
• Properties
• Advantages
• Application
• Reference

3. INTRODUCTION
• Cellular Concrete is defined as lightweight portland
cement concrete containing a high percentage of gas
cells (distinguishable from air voids in terms of cell
sizes and lognormal distribution) created mechanically
by means of the addition of foaming agents. A density
range of 320 to 1900 kg/m3 . characterizes cellular
concrete products that include CLSM (Controlled Low
Strength Material). This low density is due to the
uniformly distributed non-contiguous air cells that also
account for high workability and desirable thermal
conductivity.

4. CELLULAR CONCRETE

5. Light weight concrete (foamed concrete) is a versatile material which
consists primarily of a cement based mortar mixed with at least 20% of
volume air. The material is now being used in an ever increasing number
of applications, ranging from one step house casting to low density void
fills. Light weight concrete is a special concrete which weighs lighter than
conventional concrete. The density of this concrete is considerably low
(300 kg/m3 to 1850 kg/m3) when compared to normal concrete
(2200kg/m3 to 2600kg/m3).
Three types of LWC
• Light weight aggregate concrete -
• Aerated concrete -
• No – fines concrete
LIGHT WEIGHT CONCRETE

6. Aerated concrete does not contain coarse
aggregate, and can be regarded as an
aerated mortar. Typically, aerated
concrete is made by introducing air or
other gas into a cement slurry and fine
sand. In commercial practice, the sand is
replaced by pulverized- fuel ash or other
siliceous material, and lime maybe used
instead of cement.
AERATED/FOAMED CONCRETE

7. Aerated/Foamed Concrete
•Produced by introducing air into the
concrete.
•It is also called cellular concrete having
voids between 0.1mm to 1mm size.
•Two ways are there to induce the air in
concrete.
•Gas concrete
•Foamed concrete
• Gas concrete is produced by chemical
reaction in which gas is produced in the
concrete.
• Finely divided aluminum powder is
generally used as gas producing agent.
•Its quantity is about 0.2% of weight of
cement.
• Aluminum powder reacts with Ca (OH)2
to liberate hydrogen bubbles.

8. METHODS
•. The first method is to inject the gas into the
mixing during its plastic condition by means of
a chemical reaction. The second method, air is
introduced either by mixing-in stable foam or
by whipping-in air, using an airentraining
agent. The first method is usually used in
precast concrete factories where the precast
units are subsequently autoclaved in order to
produce concrete with a reasonable high
strength and low drying shrinkage.
• The second method is mainly used for in-situ
concrete, suitable for insulation roof screeds or
pipe lagging. The differences between the
types of lightweight concrete are very much
related to its aggregate grading used in the
mixes.

9. FOAMING AGENT
Foaming agent is a chemical which facilitates formation of foam such as
surfactants and blowing agents.
There are two types of foaming agent:
I. Synthetic-suitable for densities of 1000 kg/m3 and above.
II. IProtein-suitable for densities from 400 to 1600 kg/m3
Protein-based foaming agents come from animal proteins (horn, blood,
bones of cows, pigs & other remainders of animal carcasses). These
surfactants might therefore be best suited to the production of foamed
concrete of relatively high density &high strength.
Synthetic foaming agents are such chemicals which reduce the surface
tension of liquid and commonly used globally to make blocks, bricks,
CLC concrete etc where the high density is needed and it requires less
energy for formation as compared to other foaming agents.

10. ∙ Foaming agents:
• Foaming agents can be divided into two main groups:
• ∙ Natural foaming agents
• ∙ Synthetic foaming agents
• Natural waste based foaming agents ordinarily used in the industry are
tannic extracts of leather industry, sub soaped lye, sulfite lye – they are
the products with sufficiently varying properties. They have a limited
storage life. Due to inconsistency of raw material composition and
complicacy in their production, the chemical composition and main
component content in the foaming agent obtained is varied.

11. • Synthetic foaming agents are produced in accordance with
technical requirements so that they have permanent
properties and working life much longer; this gives them
application advantages.
• Foaming agent selection must be carried out for the particular
production in dependence on production capacity, foam
concrete mix production method and regional conditions.
• The foam is mainly added as a base material and the main
requirement is that it must be capable of remaining stable
and not collapsing during pumping, placement and
• curing. The density of the foam is about 110 kg/m3and
investigators reported that foam materials below this density
are to be manufactured with care.

12. FOAMING AGENTS
• Hydrogen Peroxide
• Plant Surfactants

13. Literature Review
• Lightweight concrete (brick) as known as AAC (Autoclaved Aerated
Concrete) is a well-known constructing material all over the world; it was
first invented by a Swedish Architect named Johan Axel Eriksson in
1923.Lightweight concrete contains no aggregate larger than sand, lime,
thermal ash, synthetic fiber, cement, aluminum powder and water as
binding agent. When AAC is mixed and cast in forms, several chemical
reactions take place that give AAC its light weight (20% of the weight of
concrete) and thermal properties. Therefore, lightweight concrete is quite
light and may suffer extreme pressure as well as insulate the high and low
temperatures.
• P.S.Bhandari and Dr.K.M.Tajne: In this research paper they have concluded
that the compressive strength for cellular light weight concrete is low for
lower density mixture.The performance of cellular lightweight concrete in
term of density and compressive strength are investigated.

14. • HjhKamsiahMohd.Ismail,MohamadShazliFathi and
NorpadzlihatunbteManaf: In this study paper the main specialties of
lightweight concrete are its low density and thermal conductivity. Its
advantages, disadvantages and applications were studied thoroughly.
•
• Satyendra Kumar Meena, Pushpendra Kumar Meena, Rakesh Kumar
Meena, Rupayan Roy and Pawan Kumar Meena: It was studied that
cellular lightweight concrete possesses high flow ability, low self-weight,
minimal consumption of aggregate, controlled low strength and excellent
thermal insulation properties.It has excellent resistance to water and frost,
and provides a high level of both sound and thermal insulation.
•
• K.KrishnaBhavaniSiram: This paper shows that how the cellular concrete
can be used as a replacement of burnt clay bricks. An attempt is made to
compare cellular lightweight concrete (CLC) Blocks and Clay Bricks, and
recommend a replacement material to red brick in construction industry.

15. Objective
• To provide sufficient strength.
• To provide low density ( for better insulation)
• For low drying shrinkage.( to avoid
cracking/rift)

16. Materials Required
• Foaming agent
• Portland cement
• approved admixtures/pozzolans
• Potable water free of deleterious material

17. FOAMING AGENT

18. METHODOLOGY
• BATCHING AND MIXING :
The dry ingredients like cement, sand, sand + fly ash or fly
ash alone shall be fed into the mixer first and thoroughly
mixed to ensure even distribution of cement. The
appropriate amount of water shall be added thereafter
continuing the mixing. The preformed foam, which is made
by blending the foam concentrate, water and compressed
air in predetermine proportion in a foam generator,
calibrated for a specific discharge rate, shall be added in
measured amount to the slurry of cement, sand, fly ash and
water in the batch mixer. After an additional mixing to get
uniform consistency, the slurry form of foamed cellular
concrete of desired wet unit weight shall be ready to be
poured out into forms/moulds etc.

19. FOAMED CONCRETE PROCESS

20. Cellular Concrete –Properties
FRESH CONCRETE
• Flowable
• Pumpable
• Easy workability
• No compaction
necessary
HARDENED CONCRETE
• Adjustable in unit
weight and strength
• durable and stable in
shape
• Thermal insulating
• higher resistance to fire
• increased shrinkage
• not decomposable

21. Physical properties
1) Drying shrinkage:
Foam concrete possesses high drying shrinkage due to the absence
of aggregates, i.e., up to 10 times greater than those observed on
normal weight concrete. Autoclaving is reported to reduce the
drying shrinkage significantly by 12–50% of that of moist-cured
concrete due to a change in mineralogical compositions. The
shrinkage of foam concrete reduces with density which is attributed
to the lower paste content affecting the shrinkage in lowdensity
mixes.
2) Low Density and High Strength: Due to its low density, foam
concrete imposes little vertical stress on the substructure - a
particularly important attribute in areas sensitive to settlement.
Heavier density (1000 kg/m3+) foam concrete is mainly used for
applications where water ingress would be an issue - infilling cellars,
or in the construction of roof slabs for example.

22. 3) Compressive strength: The compressive strength
decreases exponentially with a reduction in density of
foam concrete. The parameters affecting the strength
of foam concrete are cement–sand and water–cement
ratios, curing regime, type and particle size distribution
of sand and type of foaming agent used.For dry density
of foam concrete between 500 and 1000 kg/m3, the
compressive strength decreases with an increase in
void diameter. For densities higher than 1000 kg/m3,
as the air-voids are far apart to have an influence on
the compressive strength, the composition of the paste
determines the compressive strength.

23. 4) Flexural and tensile strengths: Splitting tensile
strengths of foam concrete are lower than
those of equivalent normal weight and
lightweight aggregate concrete with higher
values observed for mixes with sand than
those with fly ash.Use of Polypropylene fibres
has been reported to enhance the
performance with respect to tensile and
flexural strength of foam concrete.

24. EXPERIMENTS
• CUBE TEST
• BS Absorption Test
• Simple Density Test.

25. TESTING PROGRAM
• In order to study the behavior of lightweight
concrete, normal concrete testing was done to
determine the material and structural properties of
each type of lightweight concrete and how will these
properties differ according to a different type of
mixture and its composition. Once concrete has
hardened it can be subjected to a wide range of tests
to prove its ability to perform as planned or to
discover its characteristics. For new concrete this
usually involves casting specimens from fresh
concrete and testing them for various properties as
the concrete matures.

26. COMPRESSIVE STRENGTH
• Compressive strength is the primary physical property of concrete (others are
• generally defined from it), and is the one most used in design. It is one of the
• fundamental properties used for quality control for lightweight concrete.
Compressive
• strength may be defined as the measured maximum resistance of a concrete
specimen to
• axial loading. It is found by measuring the highest compression stress that a test
cylinder
• or cube will support.
• There are three type of test that can be use to determine compressive strength;
• cube, cylinder, or prism test. The ‘concrete cube test' is the most familiar test and
is used
• as the standard method of measuring compressive strength for quality control
purposes
• (Neville, 1994). Please refer appendix 1 for details.

27. WATER ABSORPTION
•
• These properties are particularly important in concrete, as well as being important
• for durability. (J.H Bungey, 1996). It can be used to predict concrete durability to resist
• corrosion. Absorption capacity is a measure of the porosity of an aggregates; it is also
• used as a correlation factor in determination of free moisture by oven-drying method
• (G.E Troxell, 1956).
• The absorption capacity is determined by finding the weight of surface-dry
• sample after it has been soaked for 24 hr and again finding the weight after the sample
• has been dried in an oven; the difference in weight, expressed as a percentage of the dry
• sample weight, is the absorption capacity (G.E Troxell, 1956).
• Absorption capacity can be determine using BS absorption test. The test is
• intended as a durability quality control check and the specified age is 28-32 days (S.G
• Millard).
•

28. DENSITY
• The density of both fresh and hardened concrete
is of interest to the parties
• involved for numerous reasons including its effect
on durability, strength and resistance
• to permeability.
• Hardened concrete density is determined either
by simple dimensional checks,
• followed by weighing and calculation or by
weight in air/water buoyancy methods (ELE
• International, 1993).

29. STRENGTH AND DENSITY
COMPARISON
•
• The purpose of this test is to identify the performance of aerated lightweight concrete in
• term of density and compressive strength.
• it can be seen that compressive strength for aerated lightweight
• concrete are low for lower density mixture. The increment of voids throughout the sample
• caused by the foam in the mixture will lower the density. As a result, compressive strength will
• also decrease with the increment of those voids.
• The required compressive strength of lightweight concrete is 3.45 MPa at 28 days as a
• non load bearing wall. The compressive strengths obtained from these mixtures carried out are
• higher than 3.45 MPa and therefore it is acceptable to be produced as non-load bearing structure.
• However, the compressive strength for the mixture with density of 2050 kg/m3 is slightly
• low compared with density of 2040 kg/m3. This is due to the compaction problem during mixing
• process. The final mixture is quite dry and since compaction is not perfectly done, samples are
• not well compacted. This has resulted the compressive strength to be lower than the mixture
• with lower density.

32. The manufacturing process of cellular light weight concrete involves the following steps:

33. Sr
no
Description Load
(KN)
Area
Mm2
Avg
strnth
N/mm2
1 CLC
Blocks(Protein based)
153.33 375000 8.96
2 CLC Blocks
(Aluminum as Foaming
Agent)
96.67 375000 5.65
3 Conventional
Clay Bricks
100 375000 5.84
: Average Strength of CLC Blocks & Conventional Clay Bricks after 21 Days

34. SL. PARAMETERS CLC BLOCKS
1 DRY DENSITY
(Kg/m3)
800 900 1000
2 COMPRESSIVE
STRENGTH
(N/mm2)
2.6 3.2 3.8
3 DRYING
SHRINKAGE
(mm/meter)
NO
SHRINKAGE
NO
SHRINKAGE
NO
SHRINKAGE
4 THERMAL
CONDUCTIVITY
(W/m.k)
0.32 0.34 0.36
5 WATER
ABSORPTION
(%)
11.87 11.51 11.37
Test Results – General Properties for water curing

35. Characteristics Type of foam concrete (cast density) Unit
Cast density 400 500 600 700 800 900 1000 1200 1400 1800 Kg/m3
Cube compressive
strength (28days)
0.1.3 2.0 3.0 3.0 4.5 5.5 6.5 10.0 12.0 16.0 Mpa
Tensile strength
(28days)
0.1 0.2 0.3 0.35
0.45
0.55
0.65 1.1 1.2 1.6 Mpa
Thermal
conductivity
0.11 0.13
0.15
0.18
0.22
0.26
0.30 0.40 0.55 0.77 W/mk
PROPERTIES OF FOAM CONCRETE:

36. Advantages of CLC (Cellular
Lightweight Concrete)
• Lightweight
• Fire Resistant
• Thermal Insulation
• Sound absorption and Acoustical Insulation
• Environmentally Friendly
• Cost-Efficient
• Speedier constructions
• Ease of work ability
• Excellent for earthquake resistant housing due to
light weight

37. Application
• CLC is preferable for thermal insulation as bricks and clocks instead of at roofs and non-
loading walls.
• The low strength material is used for old sewer pipes, wells, unused cellars and basements,
storage tanks, tunnels and subways.
• It is also used to the built a heat-insulated light wall panel. It maintains the acoustical balance
of concrete.
• Used in light heat resistant ceramic tiles.
• oil water drainage purposes.
• It is used in a bridge to prevent freezing.
• Also used for Perlite plaster and Perlite lightweight concrete
• Acoustic construction
• Precast exterior walls
• Roof insulation and waterproong ■ Green construction
• Additional floors to existing structure
• Building material for highrises
• Air-conditioned buildings
• Low cost housing
• Subway

38. REFERENCE
• P.S.Bhandari and Dr.K.M.Tajne,’’Cellular Lightweight Concrete Using Fly Ash’’,International Journal of Innovative
Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 3, Issue 11,
November 2014.
•
• HjhKamsiahMohd.Ismail, MohamadShazliFathi and NorpadzlihatunbteManaf,’’Study of Lightweight Concrete
Behaviour’’
•
• Satyendra Kumar Meena, Pushpendra Kumar Meena, Rakesh Kumar Meena, Rupayan Roy and Pawan Kumar
Meena,’’Cellular Lightweight Concrete’’
•
• K.KrishnaBhavaniSiram ,’’Cellular Light-Weight Concrete Blocks as a Replacement of Burnt Clay Bricks’’,
International Journal of Engineering and Advanced Technology (IJEAT) ISSN: 2249 – 8958, Volume-2, Issue-2,
December 2012.
•
• K.KrishnaBhavaniSiram (December 2012), International Journal of Engineering and Advanced Technology (IJEAT)
ISSN: 2249 – 8958, Volume-2, Issue-2, Cellular Light- Weight Concrete Blocks as a Replacement of Burnt Clay Bricks
• M.S.Shetty, Concrete Technology Theory & Practice, Published by S. CHAND & Company, Ram Nagar, New Delhi [5]
Van Deijk S., Foamed Concrete. A Dutch View. Pp 2-8. BRE,1992.
• IS: 383-1970 Specification for coarse and fine aggregates from natural sources for concrete (second revision), BIS,
New Delhi.
• IS : 456-2000 Plain and reinforced concrete- Code of practice (fourth revision), BIS, New Delhi.
• IS : 2185 (Part 4) 2008 Concrete masonry units- Specification preformed foam cellular concrete blocks, BIS, New
Delhi.