1) The document discusses a seminar on studying the properties of lightweight concrete using lightweight aggregate. It aims to reduce the dead load and seismic load of structures. 2) Lightweight concrete has a density of 300-1850 kg/m3 compared to normal concrete which has 2200-2600 kg/m3. This lower density is achieved by replacing normal aggregate with porous lightweight aggregate or adding gas bubbles. 3) The advantages of lightweight concrete include reducing structural loads, providing similar mechanical properties to normal concrete, and having improved workability. It allows for thinner slabs and lighter structures.

1. Seminar on
STUDY ON PROPERTY OF CONCRETE
USING LIGHT WEIGHT AGGREGATE
MORADABAD INSTITUTE OF
TECHNOLOGY MORADABAD
NAME ROLL NO
RAZ MOHAMMAD 1508200067
MUKUL KUMAR 1508200053
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2. Content
Introduction
Objective
Scope
Literature Review
Difference between LWC & HWC
Advantages of LWC
MIX Design of LWC
Use of foaming agent
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3. INTRODUCTION
• Light weight concrete is a special concrete which weighs lighter than
conventional concrete.
• Density of this concrete is considerably low (300 kg/m3 to 1850 kg/m3) when
compared to normal concrete (2200kg/m3 to 2600kg/m3).
• Basically there is only one method for making concrete light i.e by
INCLUSION of air in concrete. This is achieved in actual practice by there
different ways
i) By replacing the usual aggregate by cellular porous or LWA
ii) By introducing gas or bubbles in mortar-aerated concrete
iii) By omitting sand fraction from the aggregate-no fines concrete
• Light weight aggregate concrete - UK, France & USA
• Aerated concrete - Scandinavian countries
• No – fines concrete is less popular
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4. INTRODUCTION
Lightweight aggregate is the generic name of a group of aggregates
having a relative density lower than normal density aggregates (natural
sand, gravel, and crushed stone), sometimes and is referred to as low
density aggregate.
Lightweight concrete mixture is made with a lightweight coarse
aggregate and sometimes a portion or entire fine aggregates may be
lightweight instead of normal aggregates. Structural lightweight
concrete has an in-place density (unit weight) on the order of 90 to 115
lb / ft³ (1440 to 1840 kg/m³).
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5. o To reduce the dead & earthquake load of structure by using a
Lightweight Concrete (LWC) .
o To provide a critical overview on the production of cement and its
properties in the light of LWC and its application in civil structures.
o To present a scientific analysis on the properties of LWC using different
composition materials including both the mechanical and chemical
properties.
o To investigate on the regulations pertaining to LWC and their effects on
a specific composition of LWC in a given geographical region.
o To investigate on the LWC production and use in Greece.
OBJECTIVE
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6. o The presence of concrete in civil engineering is exhaustive
in nature and hence the research scope is limited to the
composition of the LWC and its application in civil
structure applications.
o The key aspects of the LWC and its manufacture in Greece
is also included in the scope of the research although a
global research on the LWC manufacture and regulations
pertaining to LWC is out of scope of this project.
o The research scope also includes the investigation of the
general regulations adhered in the Europe including the
ACI-318 and design considerations in the light of Seismic
Design.
SCOPE
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7. o In the USA during the 1914-1918 war, and their success led to
the production of the USS Selma (a war ship). In both 1953
and 1980 the Selma’s durability was assessed by taking cored
samples from the water line area. LWC has been successfully
used for marine applications and in shipbuilding.
o According to ACI Material Journal by Diona Marcia, Andrian
Loani, Mihai Filip and Ian Pepenar (1994), it was found that in
Japan LWC had been used since 1964 as a railway station
platform. The study on durability was carried out in 1983 has
proven that LWC exhibited similar carbonation depths as
normal concrete. Even though some cracks were reported, but
these posed no structure problems.
LITERATURE REVIEW
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8. John P. Ries and Thomas A. Holm (2006) say that although the
capital involved with the construction of LWC is high, the fact
that the low maintenance costs and costs associated with other
supporting structures during the constructions like the reduction
in steel, girders and also the reduction in the slab thickness will
balance the costs with the production of the LWC concrete mix
itself.
LITERATURE REVIEW
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9. DIFFERENCE
The aggregate material in lightweight concrete
typically has a lower density because it is more
porous. For example, it may have many
microscopic air spaces incorporated into its
structure. The result is an aggregate with a high
absorption value, which may sometimes
necessitate caution in determining the amount
of each ingredient to use. Prewetting the
aggregate before combining it with the other
ingredients may help alleviate the change in
consistency that might otherwise accompany
absorption.
Heavyweight concrete is made from aggregates
with a density between 2,080 and 4,485
kilograms per cubic meter (or between 130 and
280 pounds per cubic foot). These aggregates are
much less porous and absorbent, and the
resulting concrete has a higher mass-to-volume
ratio. The aggregate-to-cement ratio also favors
aggregate to a much greater degree than in
lightweight concrete, even though the contents of
the cement are roughly the same. Mixers and
pumps may exhibit greater rates of wear when
working with this type of material.
Lightweight Concrete Heavyweight Concrete
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10. Heavy weight aggregate Light weight aggregate
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11. ADVANTAGES OF LWC
➢ Design is flexible.
➢ Required less dimension in structure.
➢ Improves the workability.
➢ Relatively low thermal conductivity
➢ When properly prepared its strength is equal to that of a hard natural
stone.
➢ Easy to handle and hence reduces the cost of transportation and
handling.
➢ The green concrete can be easily handled and moulded into any shape
or size according to specifications.
➢ The form work can be reused a number of times of similar jobs
resulting in economy.
➢ Concrete possesses a high compressive strength, and the corrosive
and weathering effects are minimal. 11

12. LIGHT WEIGHT CONCRETE
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13. One of the outstanding structures of cast-in-place lightweight concrete in recent years is this striking War
Memorial Building in Milwaukee, Wisconsin.
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14. Mix design of LWC
• Difficult to decide water–cement ratio, due to variable water
absorption by aggregates.
• The lack of accurate value of absorption, specific gravity and
free moisture content in aggregate make it difficult to apply
water cement ratio accurately for mix-proportion
• Generally done by trial mixing.
• The density of concrete made with saturated aggregate is higher
and the durability of such concrete, especially its resistance to
frost is lower.
• Concrete with saturated aggregates will have higher density,
which is bad in freezing & thawing action.
• In rare cases, aggregates are coated with bitumen to overcome
the water absorption problem.
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15. ➢ Foamed concrete is a cementitious material having a minimum
of 20 per cent (by volume) of mechanically entrained foam in
the plastic mortar.
➢ Gas or aerated concrete, where the bubbles are chemically
formed through the reaction of aluminium powder with
calcium hydroxide and other alkalis released by cement
hydration.
➢ Air entrained concrete, which has a much lower volume of
entrained air.
Use of foaming agent
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16. Confoam - L
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