SPECIFICATIONS AND ESTIMATIONS

GROUP MEMBERS:1.PARUL PATEL-1411100042.UPALI JAMBHULE-1411100323.RUHIA SULTANA-141110042

MATERIAL-GLASS

GLASS Glass is an inorganic product of fusion that has cooled to a rigid solid

without undergoing crystallization. It may be transparent, translucent or shiny depending upon the quantities of its basic constituents such as sand, soda & lime. By varying their quantities & using certain special additives, the properties and characteristics of glass are modulated to obtain a large variety.

It is an ancient building material, which facilitated penetration of light into buildings. Once it was used exclusively for window panes, whereas nowadays there are examples of structures made of glass only. Apart from the traditional non-bearing application in engineering, it is progressively used for construction of bearing elements. The progressively stricter regulations dealing with energy efficiency of the buildings gives rise to application of special characteristics glass of high performance, but also to the more intensive research in this field. The adequate choice of the glass type can to a great extent improve the energy efficiency of the building.

Three most attractive traits of glass: the ability to transmit light, block heat and safety issues

MAIN PROPERTIES

DENSITY at room temperature-2500 KG/CU.M

MODULUS OF ELASTICITY-69 Gpa POISSON’S RATIO- 0.23 MELTING TEMPERATURE- 1500 DEGREE

CELSIUS THERMAL CONDUCTIVITY-1.7 W/m-K SPECIFIC HEAT CAPACITY- 840 J/KG-K COMPRESSIVE STRENGTH-1000N/SQ.MM

Composition

Glass is made from the following raw materials: Sand; soda-ash;  limestone; dolomite; feldspar; sodium sulphate. These substances are themselves compounds of various elements  and a chemical analysis shows that flat glass is made up from the  following materials, used in various proportions:

Silica (S2O2)                       71.0 to 78.0% Alumina (Al2O3)                  0.5 to 1.5% Iron oxide (Fe203)              0.05 to  0.15% Calcium oxide (CaO)           5.0 to 10.0% Magnesium oxide (MgO)    2.0 to 5.0% Sodium oxide (Na2O)         13.0 to 16.0% Potassium oxide (K2O)        0.0 to  1.0% Sulphur trioxide (SO3)       0.0 to  0.5%

GROWTH DRIVERS FOR GLASS CONSUMPTION

The types of architectural glasses BASIC TYPES

Annealed glass Heat-strengthened glass Tempered glass SPECIALISED TYPES Laminated glass Insulating glass Reflective glass Tinted glass Wired glass Patterned glass Glass bricks

Annealed Glass

Normal (Annealed) Glass is synonymous with flat glass irrespective of the process of manufacture. Float glass has a perfectly flat, brilliant surface, whereas sheet glass has slight distortions. Both are referred as normal (annealed) glass and can be processed to obtain many different varieties of glass for use in buildings.

Properties The properties of normal glass are: • High light transmission • Optical clarity • Can be processed to produce other glass

types such as tempered, laminated and insulating.

• Density (approximate) : 2.42 – 2.52 g/cm3 • Tensile strength : 40 N/ sq. mm • Compressive strength : 1000 N/ sqmm.

• Modulus of elasticity : 70 GPa • Coeffiient of linear expansion: 9 x10 -6 m /

mK • Available thickness: 2 mm - 19 mm • Normally available sizes up to: 2440 mm x

3660 mm (Bigger sizes can also be made) • Colour: Clear, Grey, Bronze, Green, Blue and

Pink. • Shading co-efficient: 0.5 for 12mm thick gray

to 1.0 2mm thick clear • Visible light transmittance: 20% for gray 12

mm thick to 90% for 2 mm thick clear

Heat strengthened glass Heat strengthened glass is a

type of tempered glass which has been strengthened thermally by inducing a surface compression of 422 to 658 kg/cm2 as compared to a range of 770 to 1462 kg/cm2 in case of fully tempered glass. It is a separate process. It is valued for its mechanical strength, which is twice that of normal annealed glass though half of fully tempered glass..

Properties • Density (approximate) : 2.42 – 2.52 g/cm3 • Tensile strength : 120 to 200 N/sq. mm • Compressive strength : 1000 N / sq. mm •

Modulus of elasticity : 70 GPa • Coefficient of linear expansion : 9 x 10–6 m / mK

• Available thickness : 3 mm - 19 mm • Normally available sizes up to : 2440 mm x

3660mm (Bigger sizes can also be made) • Shading co-efficient : 0.5 for 12 mm thick gray to

1.0 for 2 mm thick clear • Visible light transmittance : 20% for 6mm thick

bronze to 90% for 6mm thick clear

Tempered glass

Tempered glass is an extremely strong glass which is heat treated to a uniform temperature of approximately 650ºC and rapidly cooled to induce compressive stresses of 770 kg/m2 to 1462 kg/m2 on the surfaces and edge compression of the order of 680 kg/m2.

Properties• Density (approximate) : 2.42 – 2.52 g/cm3 • Tensile strength : 120 to 200 N/sq. mm • Compressive strength : 1000 N /sq. mm • Modulus of elasticity : 70 GPa • Coefficient of linear expansion : 9 x 10–6 m / mK

• Available thickness : 3 mm - 19 mm

• Normally available sizes up to : 2440 mm x 3660mm(Bigger sizes can also be made)

• Shading co-efficient : 0.5% for 6 mm thick gray to 0.9% 6mm thick clear

• Visible light transmittance : 20% for 6mm thick bronze to 90%6mm thick clear

Laminated Glass Laminated glass is composed of two or more layers of

glass with one or more layers of a transparent/ pigmented and specially treated plastic Polyvinyl Butyral [PVB] sandwiched between the glass layers. The glass panes (layers) can be either normal glass or tempered glass. When the glass is broken, fragments tend to adhere to the plastic [PVB] interlayer thereby reducing the risk of injury and helping to resist further damage by weather.

Properties • Density (approximate) : 2.42 – 2.52 g/cm3 • Tensile strength : 32 N/sq. M • Compressive strength : 1000 N /mm2 • Modulus of elasticity : 70 GPa • Coefficient of linear expansion : 9 x 10–6 m / mK

• Available thickness : 4.38 mm – 20.76 mm (other thickness can also be made to order)

• Normally available sizes up to : 2000 x 3210mm (Bigger sizes can also be made)

• • Shading co-efficient : 0.5% for 6 mm thick gray to 0.9% for 6mm thick clear

• Visible light transmittance : 25% for 6mm thick bronze to 90% for 6mm thick clear

INSULATING GLASS Factory assembled unit consisting of two or

more panes of glass separated by air spaces.  Moisture proof The periphery of the air spaces is

hermetically sealed.  There are two types of such sealed units:   - Organic seal type: Two or more panes of glass

separated by air spaces sealed at their    edges with an organic seal.

  - Glass edge type:  Two sheets of clear single strength or double strength glass fused together at their edges enclosing a nominal 3/16 inches air space. This type of glass is not produced with multiple air spaces.

Properties• Shading co-efficient : 0.52 for 6 mm thick gray

to 0.95 for 6 mm thick clear monolithic • Visible light transmittance : 37% for 6mm

thick gray to 87% for 6mm thick clear monolithic.

Reflective glass A metallic coating is applied to one side of the glass in order

to significantly increase the amount of reflection by the glass of both the visible and infra-red (light and heat) range of the electromagnetic spectrum. This metallic coating can be applied to clear or body tinted glass. The reflective glass imparts a mirror like appearance to the exterior of buildings under most daytime conditions. Due to the coating of metal oxides on the glass, they are widely applied as an aesthetic product in buildings for its highly reflective surface and its wide palette of colours. It reduces heat gain and glare from the exterior and allows optimum visible light transmission to the interior. It significantly reduces the air- conditioning load of the buildings. An exceptional property of solar reflective glass is that the coating of metal oxides on the glass can be achieved without affecting the transparency of the glass.

Properties :The properties of reflective glass are • Increased aesthetic appeal. • Gives enormous flexibility in designing the exterior due to

availability of number of colours / shades • Facilitates energy savings through reduction in interior

solar heat gain and cost reduction in the cost of heating and cooling systems.

• Improves occupants comfort as interior temperature variations are less and easier to control.

• Varying degrees of light transmittance and varying reflectance.

• Reduces the air- conditioning load of the buildings

• Density : 2.4 – 2.5 g/cm3 • Available thickness : 3 mm - 12 mm

• Normally available sizes up to : 2250 x3210 mm (Bigger size can also be made)

• Shading co-efficient : 0.25 - 0.552 for 6mm thick

• Visible light transmittance : 5 – 40% for 6 mm thick

TINTED GLASS Manufactured by adding a dye

at the molten glass stage   Used to minimize solar heat

gain and glare while it also absorbs heat. 

 Available in grey, bronze, green, blue and blue/green 

 Allows for increased control of comfort and energy usage

 Sizes available: Grey and Bronze -   4mm,

5mm, 6mm,8mm,and 10mm  Blue                      -   6mm  Green                   -   5mm,

6mm, and 10mm  Blue/Green           -   6mm and

10mm

THICKNESS

COST/SQ FT (RS)

3MM 224MM 305MM 356MM 388MM 7010MM 90

WIRED GLASS Fine twisted hexagonal wire

netting or mesh inserted during the process of rolling.

May be patterned, smooth rolled or ground and polished.

Used primarily in fire rated windows, doors, skylights and applications requiring a safety glazing material.

When broken, loose pieces of glass are held by the wire netting.

Georgian wire mesh, 13mm provided.

Thickness: 5 to 7 mm. Size: 3300 x 1830 mm. 

Sheet glass SHEET GLASS... There are three different kind of

sheet glasses:      - Annealed flat glass - Processed flat glass - Misc. glass Actual color green (or

sometimes blue). Sizes available:

2mm, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 15mm and 19mm.

Uses: windows,shelves,large size doors and table tops

THICKNESS COST

4-6 MM RS.53/SQM

8-12 MM RS.63/SQM

PATTERNED GLASS PATTERNED GLASS...  Sometimes referred to as “figured”

or “rolled” glass.  Has a pattern or texture impressed

on one or both sides in the process of rolling. 

This glass surface has a patterned decorative design which provide translucency and some degrees of obscurity.

 Patterns are classified as decorative or glazing i.e., used primarily for their functional properties.

Uses:  decorative glazing of windows, bathroom partitions, door.

Is difficult to clean as dust settles between the crevices

Thickness: 4mm, 6mm,  Sizes: 2140 x 1280 mm, 2140 x

1320 mm respectively.

GLASS BRICKS GLASS BRICKS... These are hollow glass units or blocks of glass

shaped to work as bricks Joined with the help of silicon sealants to

obtain seamless finish The two outer, exposed surfaces may be

smooth or textured. Glass blocks can be coloured and have

decorated surfaces.  Walls of glass blocks meeting fire resistance

are also possible. Found in Indonesian, Sri Lankan, Chinese,

USA, German varieties Srilankan and Indonesian varieties: Rs 80 per

piece European clear: Rs 350/pc  European coloured: Rs 450/pc  Chinese clear: Rs 52/pc Chinese coloured: Rs 152/pc Sizes: 71/2 “ by 71/2” by 3 “

SPECIAL GLASS COATINGS Self-cleaning or easy to clean glass Photochromatic coatings Elctrochromic coatings Thermochromic coatings

Determination of safe thickness of glass

Once the type of glass to be used is selected, section deals with the determination of appropriate thickness of glass. The thickness of the glass to be used in window panels is governed by the following factors:

i. Area to be covered by the window panel. ii. Support conditions (supported on two sides or four sides). iii. Aspect ratio of window panel (length / breadth). iv. Effective wind pressure at the window height v. Strength/load bearing capacity of glass to be used. The salient features of the procedure are as follows: • The maximum area of glass panel is restricted to 15 m2. • The maximum span of window is restricted to 4 m. • Aspect ratio of the glass panel should be greater than 1.5. If it is less than

1.5, next higher available thickness should be selected. • The factor of safety used is 2.5 considering the variability in strength of

glass. • Applicable to normal, reflective, laminated, tempered and insulating glass. • Applicable to rectangular panels properly fixed.

Safety issues occurring in contemporary glass structure are the result of the lack of knowledge of glass properties and other materials forming a composition with it, and designing, production or construction flaws. It is important to consider them so that they could be avoided. The basic measures taken to protect the glass structures are: • Application of chemically tempered glass with the polycarbonate core, allowing additional safety and durability•Application of multi-layered glass, with at least one layer of semi-tempered glass, which will prevent the unwanted displacement of glass panel in case of breakage•In case of point supported glass façades, prevention of failure chain reaction by independent support of glass panels in vertical rows, with regular distribution of stress in case of breakage of some of the panels, transferring the load horizontally to adjacent panels• In case of point supported glass facades, if possible, provide a central suspension point for the topmost panel in a row, providing an absolutely vertical position• In case of multi-layered glass, it is good practice to use one additional layer on the glass than what is required by the static design.

PRICE LIST OF VARIOUS GLASSES

Rates of 2015

COMPANIES INVOLVED IN GLASS MANUFACTURING Saint-Gobain Asahi India Goldplus group Allied glasses Float glass India ltd. ASGI India ltd.

REFERNCES -Archinomy(types of glasses used for glazing) -pdf(all about glass) -code of practice for use of glass (IS-59)