GALVANIZED IRON SHEETS

GI SHEETS MANUFACTURING

A highly automated hot dip process in conjunction with controlled temperature is employed to process the galvanized steel. In order to produce a galvanized steel with excellent resistance to corrosion, rust-free and devoid of any galvanizing defects zinc and antimony etc. of highest purity are applied with proper pre treatment of the substrate and controlled process of galvanizing. To further enhance the quality of sheet and make it white rust proof a special chemical treatment is applied on the zinc coated surface.

TYPES

THESE SHEETS ARE AVAILABLE IN TWO TYPES-
PLAIN GI SHEETS.
SIZES AVAILABLE ARE-
8’ X 3’
8’ X 4’
GAUGE-
30 , 28 , 26 , 24
CORRUGATED GI SHEETS-
SIZES AVAILABLE ARE-
27’’ , 30’’ WIDTH
8’ , 10’ , 12’ LENGTHS

USES


IT IS MOSTLY USED IN TEMPERORY STRUCTURES LIKE CONTRACTORS CABIN ON SITE, SHEDS. MANDAPS SMALL ROADSIDE SHOPS ETC…
IT IS ALSO COMMONLY USED IN INDUSTRIES.
ALSO COMMONLY USED IN VILLAGES FOR HOUSES.
USED IN MAKING TANKS.
USED FOR PARTITIONS
WAS ALSO USED IN MANUFACTURE OF PLANES..

CONSTRUCTION


Corrugations should run in a straight line between the highest and lowest points, and at a right angle to the purlins (the intermediate supports).
The overlaps (ends and sides) depends upon the sloop of the roof .
Purlin spacing should suit the end laps required for the size of sheet to be used.
Sheets should be laid so that the side overlaps are directed away from the prevailing wind.
All purlins should be in one plane and parallel to each other. They should be properly anchored to the supporting superstructure.
Ends of all sheets should be supported by purlins. The free overhang at the eaves should not exceed 300 mm.
8 mm diameter (min) hook bolts, crank bolts or coach screws, should be inserted through 10 mm diameter drilled holes.- NEVER PUNCHED - in the crown of the corrugations
THE FIXING OF THE GI SHEETS IS DONE BY J BOLTS.
A 8-10 MM DIA HOLE IS DRILLED THROUGH THE CROWN OF THE CORRUGATIONS.
THIS HOLE IS ON THE OVERLAP OF 2 SHEETS.
IT SHOULD BE DRILLED ON THE CROWN SO AS NO WATER SEEPS IN
THEY CAN ALSO DIRECTTLY BE BOLTED ON THE PURLINS..


ADVANTAGES
LIGHT IN WEIGHT.
EASY TO HANDLE.
NO SKILLED LABOUR REQUIRED.
WATER RESISTANT.
CAN BE PAINTED.
NO BREAKAGE.

DISADVANTAGES

HEATS UP QUICKLY AND MORE OFTEN.
DOES NOT HAVE MUCH LOAD CARRYING CAPACITY OVER IT.
ASTHETICALLY NOT APEALING.
RUSTS IF NOT MAINTAINED PROPERLY
WATER MAY LEAK THROUGH THE GI SHEETS AT THE CORRODED ENDS IF NOT MAINTAINED PROPERLY..
VERY NOISY ESPECIALLY DURING MONSOONS.

MANUFACTURERS
JINDAL
UTTAM
SIFTA
NIPON
TATA

MARKET SURVEY
GENERALLY THE SHEETS ARE RATED ACCORDING TO THE GAUGE OF THE SHEETS-
FOR CORRUGATED SHEETS..
GAUGE RATE
24 40 RS\SHEET
26 3ORS\SHEET
28 26RS\SHEET
30 23RS\SHEET
FOR TATA CORRUGATED SHEETS-
24 52RS\SHEET
26 40RS\SHEET
28 30RS\SHEET
FOR PLAIN SHEETS-
24 17RS\SHEET
26 14RS\SHEET
28 12RS\SHEET
30 10RS\SHEET

MATERIALS-TIMBER

INTRODUCTION
The timber is obtained by felling of trees.
Timber is used due to following reasons
climate
avaibility
site

HISTORY
Since timber was abundant in Japan it was chiefly used for construction

Timber resists earthquake.

The timber joinery is flexible.


Initially greek columns and entablature were in timber.
Later timber forms were imitated in stone with remarkable exactness, so greeks are called ‘carpenters in marble.
Since greeks did not have proper tools carving stone, timber was used.

MAIN-DANUBE CHANNEL FOOTBRIDGE, GERMANY

The site is in abroad flat river valley, between steep wooded slopes where there is an an ancient castle and picturesque village of Essing.
The bridge has a close engagement of surroundings and landscape.

ALLWELT HOUSE-WILLIAM TURNBULL

The house is traditional on outside , unique on the inside , appropriate to its context both formally and climatically due to use of timber.

FINNISH PAVILLION-ALVAR AALTO

The interior finish was of wood with different profiles so formed to create a harmonic rhythm of material and presentation of materials.
The pavillion is 52 ft high consisting of 4 storeys

BRANT HOUSE-ROBERT VENTURI

A house constructed for young people who wanted to house their collection of pop art paintings and art deco and accomodate their growing family.
To merge with the lightly wooded site timber is used for construction.

VERNACULAR ARCHITECTURE

Timber is used in vernacular architecture of Maharashtra
Timber is avaiable in the dense forests.
The post and beam construction is used.
Timber helps in maintaining cool interiors



The house is from south India.
The is built entirely in timber with pitched roof covered with manglore tiles
The plinth is in bricks.
Timber is a local material and is climatically suitable for hot and humid south India.

CONSTRUCTION TECHNIQUES
The timber after felling of trees cannot be used directly due to the large sap content.
So it has to undergo the process of seasoning.
Timber can be bent.
Timber cannot be bolted ,it can be only nailed.
The strength of the timber member is more when the forces are acting perpendicular to the grains.