Table Of Contents

Topics page No.

Abstract....................................................................................................................................................2

Introduction..............................................................................................................................................3

Figure 1. Soap foam bubbles...............................................................................................................3

Foamed glass............................................................................................................................................4

Figure 2 Foamed Glass........................................................................................................................4

Production Process...................................................................................................................................5

Figure 3 Porous Foamed Glass............................................................................................................5

Figure 4 Processing of Foamed glass..................................................................................................6

Properties of foamed glass.......................................................................................................................6

Figure 5. Foamglass in different shapes..............................................................................................8

Strength and deformation properties........................................................................................................8

Table 1.Deformation/settlements (short term/day 1) in foam glass material......................................9

Table 2.Estimated creep deformations after day 1 at stress level* 300 kN/m2 permanent load.........9

Foamed Glass In Road Projects...............................................................................................................9

Figure 6.Installing Steel Tube............................................................................................................11

EXAMPLES WHERE FAOMGLASS IS USE IN ROAD PROJECTS...............................................11

Advantages of Foamed glass.................................................................................................................12

Disadvantages of Foamed glass.............................................................................................................15

Conclusion.............................................................................................................................................15

References..............................................................................................................................................17

1

Abstract

Granulated foamed glass is produced by recirculating waste glass. It is also known as cellular

glass. It is a light weight, opaque glass material having a closed-cell structure. It is an

excellent bulk material for civil construction and insulation purposes. It is a lightweight,

extremely fine-pored expanded glass with millions of pores. Since no diffusion can take

place, the material is watertight and achieves an efficient barrier against soil humidity.

Foamed glass is produced using an environ-mentally friendly recycling technology for

contaminated and toxic material. The normal grain size is in the range 10 – 60 mm. When

placed and compacted in a drained fill the least unit density will be 300 –350 kg/m3

depending on the compaction machinery and compaction efforts. Besides the outstanding

mechanical and thermal properties of the product, foamed glass manufacture is an exemplary

process for waste recycling on an industrial basis. Foam glass can be manufactured fully out

of waste glass, with only a minimum of additives. The material may be used as a lightweight

fill material, as frost protection layer/thermal insulation in roads , insulation in buildings,

especially suitable for thin-walled thermal insulations, such as for window frames, cement

bricks and insulating plasters or other civil engineering applications. Foam glass can also

provide very effective fire protection.The material is very advantageous and is being

extensively used in construction thses days. This Report basically presents the manufacture,

usage, advantages , disadvantages and other engineering aspects of Foam glass.

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Introduction

A foam is a substance that is formed by trapping pockets of gas in a liquid or solid. A bath

sponge and the head on a glass of beer are examples of foams. In most foams, the volume of

gas is large, with thin films of liquid or solid separating the regions of gas. An important

division of solid foams is into closed-cell foams and open-cell foams. In a closed-cell foam,

the gas forms discrete pockets, each completely surrounded by the solid material. In an open-

cell foam, the gas pockets connect with each other. A bath sponge is an example of an open-

cell foam: water can easily flow through the entire structure, displacing the air. A camping

mat is an example of a closed-cell foam: the gas pockets are sealed from each other, and so

the mat cannot soak up water. Foams are examples of dispersed media. In general, gas is

present in large amount so it will be divided in gas bubbles of many different sizes (the

material is polydisperse) separated by liquid regions which may form films, thinner and

thinner when the liquid phase is drained out of the system films.[1] When the principal scale is

small, i.e. for a very fine foam, this dispersed medium can be considered as a type of colloid.

The term foam may also refer to anything that is analogous to such a foam, such as quantum

foam, polyurethane foam (foam rubber), XPS foam, Polystyrene, phenolic, or many other

manufactured foams. The same concept is used in the process of Foamed glass.

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Figure 1. Soap foam bubbles

Foamed glass

The study of thermodynamics in the late 19th century included the heat-transfer properties of

materials and led to the concept of thermal insulation—that is, a material that has a relatively

low rate of heat transfer. As building atmospheres became more carefully controlled after

1900, more attention was given to the thermal insulation of building enclosures . One of the

best insulators is air, and materials that trap air in small units have low heat-transfer rates;

wool and foam are excellent examples. The first commercial insulations, in the 1920s, were

mineral wools and vegetable-fibreboards; fibreglass wool appeared in 1938. Foamed glass,

the first rigid insulating foam, was marketed in the 1930s, and after 1945 a wide variety of

plastic foam insulations was developed. Since the 1970s most building codes have set

minimum requirements for insulation of building envelopes, and these have proved to be very

cost-effective in saving energy.

Foamed glass is A light, black, opaque, cellular glass made by adding powdered carbon to

crushed glass and firing the mixture which acts as a cellulating agent.These components are

mixed, placed in a mold, and then heated to a temperature of approximately 950 oF. During

the heating process, the crushed glass turns to a liquid. Decomposition of the cellulating agent

will cause the mixture to expand and fill the mold. The mixture creates millions of connected,

uniform, closed-cells and form at the end a rigid insulating material. It is widely used as light

weight fill material, thermal insulation in roads and buildings, and insulation under the floor

slab as well because of its light weight, low parameters of heat conductivity. It is also used in

the petroleum and chemical industries as well as underground engineering and military

projects for heat insulation, temperature conservation, cold storage and sound insulation. 

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Figure 2 Foamed Glass

Production Process

Foamglass is produced using an environmentally friendly recycling technology for

contaminated and toxic waste ranging from mercury lamps, industrial slag and flyash, PC and

TV-tubes, and laminated glass to batteries. The process is based on the concept of

transforming finely ground glass powder from different glass sources mixed with an activator

like silica carbide into glass foam. In the grinding process heavy metals are separated out and

recycled to metal melting plants.

Figure 3 Porous Foamed Glass

The powder is spread on a steel belt conveyor running through high temperature ovens

whereby the powder expands about 4 times leaving the oven as a glass foam material. When

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the product leaves the oven it will crack and separate into smaller units due to the temperature

shock. Normal grain size will be in the range of 10 – 60 mm .The production process is free

of dust and any harmful gases and does not need water at any stage.

The principles behind this system are very simple:

To separate and to clean the waste in fractions for further treatment down the process line.

During this process the toxic components are reduced below the detecting limits. In this

connection a certificate has been obtained for the material confirming that possible leaching

products from a fill will have toxic contents well below normal environmental requirements.

Foamed glass generally consists of 8 per cent of glass by volume and 92 per cent gas bubbles.

Figure 4 Processing of Foamed glass

Properties of foamed glass

Waterproof 

Foamglass insulation is resistant to water and vapour . As an all-glass, 100% closed cell

material it retains all the water-resistant properties of glass. Thus there is no moisture

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absorption, no condensation, no swelling of foamglass insulation , and it helps prevent

corrosion under insulation.

Non-combustible

Foamglass insulation is made of pure glass, and is non-combustible and also non-absorbent.

As an inorganic material foamglass insulaton will not burn or support combustion. It ensures

fire protection; inflammable liquids and gases cannot pass through Foamglas insulation .

Resistant To attack

Since Foamglass insulation is inorganic, it is resistant to birds or vermin and has an unusually

long term life cycle. Insulation of buried pipes and underground constructions is safe as

foamglass insulation provides no food or nesting source for birds or vermin and does not

support the growth of micro-organisms and bacteria.

High Compressive strength

Cellular glass insulation gives exceptionally high compressive strength without deformation

under permanent load. The insulation will not compress or settle and provides full support to

tank bases and pipe supports, without thermal bridges.

Dimensionally Stable

Cellular glass insulation is dimensionally stable, as glass does not shrink or swell. No

warping or buckling with foamglass insulation . It remains stable since it has a similar

expansion/contraction coefficient to steel piping and equipment. This gives a minimum of

stress to the insulation system, joints and coverings as temperature changes. Preventing

excessive expansion/contraction of insulation materials is the best way to ensure that the

system remains sealed against moisture.

Acid resistant / chemical resistant

Foamglass insulation is resistant to organic solvents and nearly all acids, since it is made of

pure glass.  No destruction of the insulation by sour gas or other corrosive media and

aggressive plant conditions. The chemical resistance of glass is universally recognized.

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Easily Cut to shape

Foamglass insulation can be easily cut and installed on site or  Prefabricated and pre-

assembled components are available: segments, T-piece, elbows, half pipe-shells, valve

boxes, vessel dome, ends and cones. Depending on project requirements, cellular glass

insulation can be easily cut on site using a hard-point saw and other simple tools.

Figure 5. Foamglass in different shapes

Strength and deformation properties

In Norway for a road project the foamed glass material was tested in a large cyclic loading

triaxial apparatus with diameter 300 mm to find the resistance to develop permanent

deformation when exposed to repeated loading. The results are relevant for designing road

applications where the material is used in the road structure as part of the base layer or the

sub-base layer. For use in road structures the material has elastic properties comparable to

ordinary gravel commonly used as

a roadbase material. It is, however, important that the stress level is kept below a level that

will result in crushing and permanent material deformations. For repeated loading

applications the cyclic stress is recommended limited to 75 kPa to reduce the permanent

deformations.

A large oedometer with diameter 500 mm was used to measure deformations in the material

when exposed to permanent loading. The results are shown in Table 3. The test programme

was expanded to include long term creep tests to find characteristic values for possible long

term deformation. The typical use until now has been up to approximately 100 kN/m2 base

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pressure and the experience show no damaging long term deformations for any projects. The

long term creep tests will make it possible to estimate the long term deformation for different

loading conditions. The already performed oedometer tests are used to estimate the amount of

long term creep assuming a linear time resistance development. Results are shown in Table 4.

However, long term creep test have to be performed to verify these estimates.

Table 1.Deformation/settlements (short term/day 1) in foam glass material

Quality & compaction

level \ Stress level

50 kN/m2 100 kN/m2 300 kN/m2

Light 1% 4% >15%

Light 0.25% 1.3% >11%

Standard 0.3% 1.1% >10.5%

Table 2.Estimated creep deformations after day 1 at stress level* 300 kN/m2 permanent

load

Compaction

level

1 year 5 years 25 years 100 years

1.25 2.9% 3.8% 4.6% 5.3%

1.34 2.0% 2.6% 3.1% 3.5%

Thermal Conductivity

The material is very suitable as thermal insulation and frost protection in both building and

road application. The insulating properties have been tested in laboratory and for dry,

compacted material a thermal conductivity of 0.11 W/mK at +10 ºC has been found.

Foamed Glass In Road Projects

The amount of glass products used in the western hemisphere is huge. This comprises various

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sorts of glass waste originating from light bulbs and other lighting fixtures like mercury

lamps, bottles, windowpanes, car windshields etc. and industrial waste. In Europe the average

annual glass consumption is about 30 – 40 kg/per inhabitant. At the same time as being a

waste product it also constitutes a raw material for possible reuse. Some of the glass waste

may be used directly in the production of bottles and other products but some of the glass

waste also contains toxic materials that need to be removed in the recycling process. In this

connection a production process has been initiated based on the recycling of waste glass in

the middle region of Norway. In Norway about 4 million mercury lamps are used every year

and the aim is to recycle about 40 % amounting to an annual production of some 50,000 m 3

of foamglass. In the production process lighting fixtures and other toxic glass waste is treated

in order to remove heavy metal components and other environmentally difficult matter. The

product has now been used as a lightweight filling material on about 25 road projects in

Norway and a monitoring program has been initiated in order to evaluate the material

properties and the structural performance.

With its light weight and good drainage and insulating properties the material may both be

used as a lightweight fill material and/or frost insulating layer. A continuous work to improve

the material since the start of production has resulted in a material that has a different pore

structure, density and strength today with improved structural performance compared to the

original product.In order to investigate physical and mechanical properties various

monitoring programmes have been initiated both for field and laboratory testing.

In Norway a test is conducted on existing foamglass fills by inserting and vibrating a thin

walled steel tube (with typical diameter 400-570 mm) into the foamglass (Figure 6). The

particles contained within the steel tube are removed and the excavated material weighed wet

and dry. This test is often conducted to find out changes in deformations, water content and

density. The average density of foamed glass is found to be 300kg/m3.

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Figure 6.Installing Steel Tube

EXAMPLES WHERE FAOMGLASS IS USE IN ROAD PROJECTS

A cut and cover concrete tunnel of about 600 m length was constructed as a part of the

relocation of the main highway E6. In order to keep the traffic running during the

construction period a temporary diversion road with an embankment height of more than 15

m was constructed above the concrete tunnel. The upper 6 m of the embankment consisted of

lightweight fill materials to reduce the weight on the culvert and to improve stability and

reduce settlement problems. Both light weight aggregates (9000 m3) and foamglass (1000m3)

are used. The diversion road was in service for one year until March 2004. The lightweight

fill materials are reused as backfill against bridge abutments and in other parts of the road.

Placing and compaction was performed in 1 to 1.5 metre thick layers using crawler mounted

dozers with track loads ≤ 40 kN/m2 performing some 3 passes over the area per layer. A

volume reduction of 25 % was observed. Another 5 % reduction in volume was anticipated

due to transport on site from local storage areas. No covering soils were placed on the

foamglass slopes on the temporary fill. Density and water content measurements were

performed throughout the construction period both on loose material delivered on site and on

compacted material in the fill. Plate bearing tests and falling weight measurements (FWD)

were also performed. Settlements were observed and was found to be very less.

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Foamglass insulation used at Ayers Rock Resort.

Named after the soaring white sails that crown its roof tops, Sails in the Desert Hotel at

Voyages Ayers Rock, located in the central Australian outback, is part of a worldclass resort

surrounded by the Uluru-Kata Tjuta National Park, in Australia’s Northern Territory. With a

desert climate that has average temperatures ranging from 19° C (66° F) in winter to 40° C

(104° F) in summer, effective and efficient heating and cooling for the five hotels and

multiple resort structures is a major task for the facility management engineers at the

Voyages Ayres Rock Resort. In total, over 20,000 linear meters of foamglass insulation is

currently being used at the Voyages Ayers Rock Resort. In addition to the outstanding long-

term thermal performance and compressive strength qualities, several environmental

concerns and regulations also played a role in the decision to use foamglass insulation. n.

Because foamglass insulation is made from sand and is 100% natural and inorganic, it is the

ideal choice for environmentally sensitive areas. Foamglass insulation contains no toxic

chemicals or blowing agents and poses no environmental risks.

Advantages of Foamed glass

Foamed glass makes buildings inaccessible for temperature shocks but permeable for vapor.

so it creates comfortable and stable conditions for work and rest. Moreover foamed glass is

very durable material and there is no need of making wearisome repairs of insulation.

Foamed glass is also good for reconstruction of old buildings because it is absolutely safe and

handy for use.

The basic advantages of foam glass

1. Life cycle

The guaranteed foam glass blocks life cycle with preservation of physical characteristics

values is equal to term of building operation and exceeds 100 years.

Experimental researches of the objects warmed with foam glass more 50 years ago have

shown absence of essential changes in a foam glass structure. The factor of preservation of

heat-shielding properties during all building existence is especially important in view of

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inaccessibility heat-insulated material after the end of works. Foam glass is not subject to

ageing for some reasons since its unique properties resist to active factors showing

themselves eventually:

Oxidation: The active oxygen containing in atmosphere does not render influence on

foam glass for the reason that this material consists exclusively of the higher oxides

silicon, calcium, sodium, magnesium, aluminium;

Erosion: As foam glass has no soluble components in its structure, there is no

dissolution and washout of a material with water;

Temperature drops: Foam glass has very low coefficient of linear expansion that

allows to transfer daily and annual temperature perturbation without damage for

structure of a material;

Freezing of water:  At freezing water extends and can destroy even such strong

minerals as basalt and granite, flowing in cracks. The surface of foam glass consists of

hemispheres, the material represents closed cells at all excluding hit of water inside,

therefore expansion of water does not destroy foam glass;

Deformation:  Cellular glass is not deformable absolutely and very strong material

for its density, that completely excludes an opportunity of its shrinkage, whipping,

etc. consequences of gravity and mechanical long influence;

Activity of biological forms: Foam glass is not a nutrient medium for a fungus,

mould and microorganisms, it is not damaged with roots of trees, therefore activity of

biological forms does not harm to a material structure during the time.

2. Strength

Foam glass is the strongest of all effective heat-insulated materials. Foam glass is unique that

is not compressed material absolutely. Moreover, less strong than foam glass heat-insulated

material demands anchoring to a bearing structure of a construction.

3. Stability of physical parameters

Foam glass is the material consisting from hermetically closed hexagonal and spherical cells.

Such structure of a material excludes interaction of the gas environment of cells with an

atmosphere and causes invariance in time of material’s characteristics. That is, there is no

change of such parameters of foam glass blocks as heat conductivity, strength, stability, form,

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etc. Eventually a factor of keeping heat-insulated material’s properties is important especially

at upkeep of buildings and constructions in view of inaccessibility of a material after end of

works.

4. Chemical and biological action stability

Glass of which foam glass consists by 100 % , is not decomposed with chemical reagents, is

not nutrient medium for fungus, mould and microorganisms, is not damaged with roots of

plants, is absolutely impassable for insects and rodents and represents an ideal barrier to

similar pests.

Foam glass in addition is very good abrasive material. This feature of foam glass is used

actively at a heat-shielding of granaries, industrial food refrigerators, warehouses since foam

glass is reliable barrier on a way of wreckers besides a heat-protection layer.

5. Incombustibility and fire resistance

Foam glass is completely non-inflammable material as it does not include oxidized or organic

components. The "know-how" of foam glass is such, that a finished article is fabricated as a

result of manufacturing in furnaces at the temperature close to 1000°C, therefore at foam

glass heating up to warm temperature it only melts as usual glass without extraction of gases

or vapor. This factor is important for fire-prevention properties of a construct.

6. Moisture resistance, water resistance and non hygroscopic property

Water does not render on foam glass any influence for two reasons. First it consists of

hermetically closed cells which walls` material is usual silicate glass. Secondly it does not

absorb moisture and does not pass it, and it is an additional hydro barrier at use in a building

envelope. At damage of a waterproofing distribution of water is not supposed both in vertical

and in horizontal directions.

Water resistance of foam glass allows it to prevent ice formation for long, to provide overall

protection against corrosion and excellent thermoregulation. Foam glass is steady to action

both fresh and salty water.

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7. Ecological and sanitary safety

Ecological and sanitary safety of foam glass allows to warm filler structures not only for

housings in which the raised cleanliness of the air is necessary (buildings of educational and

medical function, sports constructions; museums; hi-tech manufactures, etc.), but also for

buildings with special sanitary-and-hygienic requirements (the food and pharmacological

industry; baths and saunas; pools; cafe, restaurants, dining room, etc.)

Most foam glass is made by grinding glass from a glass melt into small particles and then

mixing it with a carbon containing material and then reheating it up above the melting point

of the glass in a box mold. The carbon material reacts with the glass to make carbon dioxide

to make the foam. The glass used is mostly recycled glass, but the double heating and the

grinding process makes the product expensive, but the product has as very long life compared

to organic products and more durability.

Disadvantages of Foamed glass

Foam glass to the maximum extent satisfies all requirements imposed. A method for

production of this material was developed as early as the ends of 1930s by I.I Kitaigorodskii

and B.Long. Unfortunately, despite obvious advantages of foamglass it did not find wide

application. However interest in this material in our country has been growing lately.

Possibilities of buying cellular glass has appear not very long ago. But for such a short time it

has gain a market because of it's unique properties. Everyday, more and more people begin to

warm their houses, flats with a cellular glass, again making sure that this material is totally

environmental, safe, secure and absolutely incombustible. The base of this material is glass,

so it can't be strike by fungus and bacterium. Besides it doesn't maintain burning, doesn't send

off toxic substances and smoke. Cellular glass is acidproof and steamproof. The one and only

disadvantage of cellular glass is it's price. During the production there are a lot of power

inputs, that's why the prise is so high. And with the prices rise on a energy resourses, the

price on a cellular glass will rise too.

Conclusion

The material is believed to be an interesting alternative as lightweight fill material and

Thermal insulation for a number of civil engineering applications. Foamglass granulate has

light weight and good insulating and drainage properties. The design densities for foamglass

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are found to be be 3.5 kN/m3 for the light quality and 4.0 kN/m3 for the standard quality.

Foamglass may be used as light weight fill in embankments to improve stability and or

reduce settlements and as frost insulation layer. The material is believed to be fully resistant

to possible chemical degrading agents in a road structure. The mechanical strength of the

light quality material may require some special handling in order to prevent excessive

crushing. Observations so far indicate that fairly light machinery should be used on site for

placement, distribution and compaction. The material is also being used in Our country for

insulating residentital and other buildings . Foamed glass has found an important place in

construction of buildings and road and tunnel projects because of its favourable properties. It

is a good fire resistant and does not have any environmental impact.\

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References

1) Aabøe Roald, 1980, “Lette fyllmasser I vegbygging” (lightweight filling materials

in road construction – text in Norwegian), Intern rapport 954, Norwegian Road

Research Laboratory, Oslo

2) S. Basak, S. S. Mukherjee, S. N. Mandal, Rama Das, A. K. Majumdar, J. K.

Mondal, R. Samaddar, S. Mondal and Dipali Kundu* ‘Interlaboratory proficiency testing:

Intercomparison in relation to the measurement of alumina, iron(III) oxide and titania present

in homogenised china clay’, in MAPAN-Journal of Metrology Society of India (in press),

2010

3) http://www.mendeley.com

4) www.google.com

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