Light Wight Concrete

SEETHI SAHIB MEMORIAL POLYTECHNIC COLLEGE

TIRUR-5

DEPARTMENT OF CIVIL ENGINEERING2014-2015

Seminar report on

Lightweight Concrete

Submitted by:-

ANOOP.KRoll No: 5

Reg.No: 12011146

Seminar Report 2014-2015 Lightweight Concrete

SSM POLYTECHNIC COLLEGE

TIRUR

DEPARTMENT OF CIVIL ENGINEERING

2014-2015

CERTIFICATEThis is to certify that this is the bonafide record of seminar on

Lightweight Concrete has been presented by ANOOP.K, sixth semester

Civil Engineering, SSMPTC, Tirur on……………………………. In par-

tial fulfillment of the requirement for the award of the Diploma in Com-

puter Engineering under Directorate Of Technical Education, Kerala

State during the year 2014-2015.

Staff in charge: Head of Section:

External Examiners: Internal Examiner:

Place:

Date:

2Dept. of Civil Eng. S.S.M Polytechnic College, Tirur


ACKNOWLEDGEMENT

First of all I would like to praise the god for blessing me to

complete this seminar successfully.I am deeply incepted to Mr.

Mohammed Iqbal M (Head of department in Civil engineering, Seethi

Sahib Memorial Polytechnic College ,Tirur) for providing me the

opportunity to present the seminar on this topic.

I extended my unexplainable gratitude towards all of my

teachers; especially to Mr. Abdul Naser Kokkodi(Lecturer in Civil

engineering, Seethi Sahib Memorial Polytechnic College, Tirur) &

librarians who gave me a lot of information and supports for this

seminar.I gave my heart full thanks to my friends & family, whom

offered me all kind of supports for this.



CONTENTS

ABSTRACT 05

INTRODUCTION 06-07

BASIC CHARECTERS 08-09

HISTORY OF LWC 10-11

ADVANTAGES OVER NWC 12-13

APPLICATIONS 14

NEW OPPORTUNITIES AND CHALLENGES 15-16

CONCLUSION 17

REFERENCE 18

ABSTRACT4

Dept. of Civil Eng. S.S.M Polytechnic College, Tirur


Lightweight concretes can either be lightweight aggregate con-

crete, foamed concrete or autoclaved aerated concrete (AAC). Such light-

weight concrete blocks are often used in house construction. Nearly all

LWACs are fire resistant. In addition, depending upon the densities and

strength, the concrete can be easily cut, nailed, drilled, and chased with

ordinary wood working tools. Lightweight concrete is expensive, but the

cost is calculated not just on the basis of aggregates or LWAC. The bond

between the aggregate and the matrix is stronger in the case of LWAC

than in normal concrete. Cement paste penetrate inside the aggregates due

to their porous nature. Thus, there is very little or no ITZ between the ag-

gregates and the matrix. Simply, it’s a type of concrete made with light-

weight aggregates.

INTRODUCTION5

Dept. of Civil Eng. S.S.M Polytechnic College, Tirur


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.

Wet (Uncompleted) Lightweight concrete at Thien Nam Phuong Ltd



In Japan, lightweight concrete is used to support the

building foundation against the earthquakes. Lightweight

concrete technology is quite friendly with the environment by

reducing five times the amount of carbon dioxide of the

production from the raw material process till the recycle wastes

process. Since the born of lightweight concrete in building

industry, baked bricks (made from natural clays) in developed

countries are banded to protect the environment and national

resources. On the other hand, lightweight concrete with the gas

bubbles structure (up to ⅛ inch in diameter) is applied popularly

by developed countries with high technologies such as United

States of America, Germany, France, Japan, etc. in handling

multiple geography technical issues such as making the

foundation for highways, anti-slip subsidence in the

mountainous areas or weak land areas to bring back huge

economic benefits.

Because of its advantages, lightweight has taken an

important part of developed countries such as Europe, North

America, and North Asia as well as the attention of some

developing countries in replacing its traditional building

material which is red brick, regular concrete and clay block.



BASIC CHARACTERS

Lightweight concrete, similar to normal weight concrete, is a mix-

ture of water, Portland cement or Ordinary Portland Cement (OPC), and

aggregate. It is classified as structural or nonstructural concrete depend-

ing on strength and compression rating, generally determined by the type

of aggregate material used in the concrete mix. Lightweight aggregate

concrete uses a variety of aggregates with lower density than normal

weight concrete.

Structural concrete, whether an approved lightweight or a normal

weight concrete, is used for applications calling for a high level of

strength and compression rating. These might be highway overpasses,

bridges, high-rise buildings, and construction in areas prone to earth-

quakes. Advantages of structural lightweight aggregate concrete with a

correspondingly reduced weight load include reduced dead loads, or

weight of the structures it's used to build, and more efficient transport.

While not approved for many structural applications, nonstructural

lightweight concrete is used where normal or a more dense structural

lightweight mix would be impractical. Roof tiles made of lightweight

concrete are lighter and require less robust truss systems. The combina-

tion of strength, weather resistance, and reduced weight often makes

lightweight aggregate concrete mix and lightweight blocks a good choice

for non-traditional residential buildings.



Aggregates used to make lightweight aggregate concrete vary. Ex-

panded shale, slate, and clay, often fired in a kiln to increase porosity, are

among aggregates used for structural lightweight concrete. Other porous

material, such as air-cooled blast furnace slag, is often used.

Insulation is often a factor in selecting an aggregate for nonstruc-

tural lightweight concrete. A lightweight aerated concrete may be used to

make both lightweight panels and lightweight blocks suitable for a variety

of construction, including some foundation stem walls. Lightweight aer-

ated concrete may be made in a variety of ways, such as forcing air into

slurry of OPC and a porous material, or by using a stable foam product as

an aggregate.

Perlite and vermiculite are natural minerals that, when heat-treated,

can be mixed with OPS to produce a nonstructural lightweight aggregate

concrete. The product is often used for decorative concrete treatments,

roof tiles, and other lightweight applications. This lightweight concrete is

often used in jobs requiring insulation from heat and sound.

Structural lightweight aggregate concrete might typically require a

density or unit weight of 90 to 115 lb/ft³ or (1440 to 1840 kg/m³) and a

compression rating of 2500 psi or (1700 MPa), which is about 65% of the

density or unit weight of normal concrete. Nonstructural lightweight con-

crete might have a density or unit weight as low as 35 lb/ft³ or (561 kg/

m³). When considering lightweight concrete for a construction job, it is

generally a good practice to consult a qualified engineer or architect for

specifications.


http://www.wisegeek.com/what-is-decorative-concrete.htm

http://www.wisegeek.com/what-is-vermiculite.htm

http://www.wisegeek.com/what-is-aerated-concrete.htm


HISTORY OF LIGHTWEIGHT CONCRETE

The use of lightweight (LWAC) can be traced to as early as

3,000BC, when Mohenjo-Daro and Harappa were built during the Indus

Valley civilization. In Europe, the use of LWCA occurred 2,000 years

ago when the Romans built Pantheon, the aqua ducts, and the Coliseum

in Rome. The pumice is still used today in certain countries, such as Ger-

many, Italy and Japan. In some places like Malaysia, palm oil shells are

used for making LWAC.

The Roman Temple Constructed using LWAC

Earlier lightweight aggregates (LWAs) were of natural origin,

mostly volcanic: pumice, tuff. They function as active pozzolanic materi-

als when used when used as fine aggregates. Techniques have been devel-

oped to produce them in factories. These are produced from the natural



raw materials like expanded clay, shale, slate, etc., as well as from by-

products such as fly ash, blast furnace slag, etc.

Pont du Gard built by romans (2000 years ago)

Today, lightweight aggregates are produced in a very wide range of

densities varying from 50kg/m3 from expanded perlite to 1000kg/m3 for

clinkers. It is possible to make LWAC of 80Mpa compressive strength

Nearly all LWACs are fire resistant. In addition, depending upon the

densities and strength, the concrete can be easily cut, nailed, drilled, and

chased with ordinary wood working tools.



ADVANTAGES OVER NORMAL WEIGHT CONCRETE

One of the main advantages of conventional concrete is the self-

weight of concrete. Density of normal concrete is of the order of 2200 to

2600. This self-weight will make it to some extend an uneconomical

structural material.

Self-weight of light weight concrete varies from 300 to 1850

kg/m3.

It helps reduce the dead load, increase the progress of building

and lowers the hauling and handling cost.

The weight of building on foundation is an important factor in the

design, particularly in case of weak soil and tall structures. In

framed structure, the beam and column have to carry load

of wall and floor. If these wall and floor are made of light weight

concrete it will result in considerable economy.

Light weight concrete has low thermal conductivity. In extreme

climatic condition where air condition is to install the use of light

weight concrete with low thermal conductivity is advantageous

from the point of thermal comfort and low power consumption.

Only method for making concrete light by inclusion of air. This is

achieved by :-

o Replacing original mineral aggregate

o By introducing gas or air bubble in mortar



o By omitting sand fraction from concrete. This is called no –

fine concrete.

Light weight aggregate include pumice, saw dust rice husk, thermo

Cole beads, formed slag. Etc.

Light weight concrete aggregate exhibit high fire resistance.

Structural lightweight aggregate’s cellular structure provides

internal curing through water entrainment which is especially

beneficial for high-performance concrete

lightweight aggregate has better thermal properties, better fire

ratings, reduced shrinkage, excellent freezing and thawing

durability, improved contact between aggregate and cement

matrix, less micro-cracking as a result of better elastic

compatibility, more blast resistant, and has better shock and

sound absorption, High-Performance lightweight aggregate

concrete also has less cracking, improved skid resistance and is

readily placed by the concrete pumping method

Aerated concrete is made by introducing air or gas into a slurry

composed of Portland cement.

No fine concrete is made up of only coarse aggregate, cement and

water. This type of concrete is used for load bearing cast in situ

external walls for building. They are also used for temporary

structures because of low initial cost and can be reused as

aggregate.



APPLICATIONSLight weight concrete is a good alternative for normal weight con-

crete. It widely uses in the following areas:-

Building industry

Road Construction

Mining

Land filling

Tunnels



NEW OPPORTUNITIES AND CHALLENGES

When constructing buildings, especially high-rise building, the in-

vestor always tries to make the structures sustainable and cost-effective.

The way to acquire both of these two depends mostly on the foundation

of the building. However, the foundation depends on the geology and the

total mass of the whole project. Changing the geology is difficult, more

feasible is to find ways to reduce the loading capacity. Hence, the birth of

light weight brick is considered as a revolution for the construction indus-

try. Light weight bricks are made from cement; thermal ash, synthetic

fibers (possible) and foaming agent to make the composition inside pos-

sess chambers forming as a honeycomb. This helps the brick become por-

ous and reduce the weight of brick from 600 kg/m3 to 900kg/m3 (D600 -

D900) as ½ lighter than common brick, and easier to drill, cut or nail di-

rectly onto the tile surface. The brick can even float on water.

There are various kinds and sizes of lightweight concrete to be

used widely from small projects to high rise buildings. The costs also suit

each project. Lightweight concrete is a great construction material. It is

not only low derivative, high thermal resistant, envi-ronmental protected



but also energy-cost saving compared to traditional materials. Pro-ducing

traditional materials waste industrial land, coal and in the same time,

causes greenhouse effect by eliminating millions tons of CO2.

Conversely, lightweight con-crete limits environmental bad impacts and

recycles a significant amount of industrial waste, turning waste into

useful materials.

Due to its benefits, lightweight concrete has become the general

trend of the world. In China, the new type of building materials accounts

for more than 55% in 2010. In Brit-ain, lightweight concrete is about 70%

of the total building materials. With the global trend, Vietnam

Government is trying to take full advantage of lightweight concrete as

well by approving the Decision No. 121/2008/QD-TTg dated 29/08/2008

of the Prime Minister. The Decision shows the master plan and route for

developing materials in Vietnam till 2020: lightweight concrete in 2010

will account for 10% to 15% and in-crease from 20% to 25% in 2015 and

in 2020 the rate will reach 30% to 40%. Under-standing the great

opportunity, Thien Nam Phuong Co., Ltd is established to manufac-turer

lightweight concrete with development objective not only to cover South

Market of Vietnam but also the whole domestic market and export to

other countries in the near fu-ture. The company’s goal is to produce and

sell 150,000 m3 / year. Although using lightweight concrete provides

much economical and technical efficiency, there are still a lot of

challenges that Government and manufacturer have to confront.



CONCLUSION

As a construction material, lightweight concrete is a good alterna-

tive for normal weight concrete.it has so many advantages over

normal weight concrete.

The use of lightweight (LWAC) can be traced to as early as

3,000BC, when Mohenjo-Daro and Harappa were built during the

Indus Valley civilization.

Today, lightweight concrete is widely used for Building industry,

Road Construction, Mining, Land filling, Tunnels, etc.

There are several new opportunities and challenges in the field of

lightweight aggregate building industry.



REFERENCE

http://www.concretecentre.com/

http://www.nrmca.org/aboutconcrete/cips/36p.pdf

http://foamconcreteindia.in/

http://www.stalite.com/uploads/engineeringproperties.pdf

http://www.litebuilt.com/lightweight-concrete-handbook.html

http://www.ecosmarte.com.au/construction/lightconcrete.htm


Documents

Light Wight Concrete