Presented By:Presented By:

Engineer LATIF HYDER WADHOEngineer LATIF HYDER WADHO

Mehran University of Engg: & Technology Khairpur Mehran University of Engg: & Technology Khairpur

Civil Engineering MaterialsCivil Engineering Materials

11stst Term 1 Term 1stst Year B.E.Civil Year B.E.Civil

Tiles:A tile is a special type of brick which is often larger than an ordinary brick.Tiles are mostly used for roofing and paving purposes.Standard size of tiles:Tiles are manufactured in different sizes in Pakistan. The most popular sizes are:

(1)12’’ x 6’’ x 1 1’’ 4

(2) 12’’ x 6’’ x 2’’(3) 9’’ x 4 1’’ x 2’’

2

CLASSIFICATION OF

TILES:

Tiles are classified into groups on the basis of construction material.

(1) Material basis

(i) Common tiles

(ii) Encaustic tiles

Depending upon their Use

(1) Roofing Tiles(a) Plain Tiles(b) Pot Tiles(c) Allahabad Tiles(d) Mangalore Tiles(e) Concrete Roofing Tiles

(2) Flooring/Paving Tiles(3) Drain Tiles

(1) CLASSIFICATION

OF

TILES

BASED UPON

MATERIAL USED

(i) Common tiles:Common tiles may be used for roofing. Flooring and walling also. Common tiles are pan tiles, pot tiles and flat tiles.(ii) Encaustic Tiles:These tiles are prepared by mixing colors with the clay before burning. These are used for decorative purposes.

(2) CLASSIFICATION OF TILES

BASED UPON THEIR USE

(i) Roofing tiles:These may be flat like slates or

may be made to different shapes. Some of the common varieties are discussed below.

(a) Plain tiles:The size of these tiles is 25 cm x 15 cm to 28 cm x 18 cm and thickness varies from 10 mm to 17 mm. (b) Pan tiles:These tiles are curved in section. These are 33 cm to 38 cm long and 23 cm to 28 cm wide

(c) Pot tiles:These are semi circular in section and taper along the length. The diameter at larger end is about 23 cm and at the smaller end it is about 20 cm.

(d) Allahabad tiles:These consist of two sets of tiles. The lower ones are flat tiles with upturned sides. End widths reduce from 27 cm to 23 cm and the length is about 38 cm. The over tile is half round in section and tapers from 16.5 cm to 12 cm in diameter. Half round tiles are moulded on a potters’ wheel as a round tapering cylindrical tile. Two longitudinal cuts are given to the cylinder while still not dry. With this it is easy to break it into two semicircular tiles after burning.

(e) Mangalore tiles:

These are flat pattern tiles with suitable key projection. About 16 tiles are required to cover one square meter of roof.

(f) Concrete roofing tiles:Tiles of any shape, size or colour could be made with cement concrete. These are more strong, durable and weather resistant.

(2) Flooring or Paving tiles:

These are usually thicker than roofing tiles and vary from 15 mm to 30 mm in thickness. Their shapes are square, hexagonal or any of other geometrical pattern and may be coloured, if desired.

Depending upon properties of clay flooring tiles are classified as: class 1, class 2, class 3 tiles. Maximum water absorption percentages in case of these tiles are 10, 19 and 24 respectively.

(3) Drain tiles:These are curved tiles made in various shapes and sizes to suit the work in which they are to be used. Tiles to be used in the construction of sewage carrying drains should be glazed.

MANUFACTURING OF

TILES

MANUFACTURING OF TILES:Six main operations are involved in

the manufacturing of tiles:1. Selection of suitable clay2. Preparation of clay3. Moulding4. Drying and Shaping5. Burning6. Cooling

(1) Selection of suitable clay:For manufacturing of tiles, we require superior type of clay. The clay should be completely free from grit, pebbles and other organic matter.

(2) Preparation of clay:

This is done by mixing water with clay in a tank and storing it in damp condition. The solution is then allowed to stand quietly in the tank resulting in the setting and leaving of coarse particles. Water containing fine clay in solution is rained off to other tanks where it is allowed to dry leaving fine clay ready for moulding.

(3) Moulding:Moulding operation is done on the ground specially prepared for that purpose. All the instruments which are used in the moulding should be present.The moulder sprinkles ashes over the clay and start to mould according to the required size of tiles on the smooth and leveled surface, when the number of 10 to 15 tiles are prepared they are taken for drying and shaping.

(4) Drying and Shaping:

Two days after moulding, the tiles are given proper shape and then they are placed on their edges and dried for about two days. One thing should be kept in mind that we take care to crack and wrap and they should be dried slowly.

(5) Burning:Tiles are burnt in a kiln which is in circular shape. Tiles are kept on their edges and door ways are closed with bricks. The maximum temperature of tiles should be 2200degreeF for about three hours. This process is repeated for second time.The kiln is isolated after it has cooled down. The kiln should be protected against bad weather specially on the wind side by temporary roofing.

(6) Cooling:After burning, cooling is done for 3 to 5 days.

(OR)3 to 5 days are required for cooling of tiles.

THE PLEASANT END