Manufacturing Bricks

Bricks

• A brick is a block, or a single unit of a ceramic material used in masonry construction.

• Bricks are typically produced in common or standard sizes in bulk quantities.

• It is one of the longest lasting and strongest building materials used throughout history.

HISTORICAL DEVELOPMENTS IN MASONRY

• It is the simplest of all the building techniques.

Sun-dried bricks - With the availability of fire became burnt bricks

Invention of kilns made mass production of bricks easy

Limestone turned into lime mortar replaced mud as mortar

Masonry History

Rich History Through the mid-1800s

– Primary Building Materials Late 1800s

– New Products Developed– Ended Masonry’s Dominance

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Brick Masonry - Uniqueness

Fire Resistance

Size

Durability

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MANUFACTURE OF BRICKS FROM CLAY

• Constituents: Brick clays are produced by blending together various clays (surface clays, shales, and fire clays) to produce the desired chemical composition and physical properties.

STEPS FOR BRICK FORMATION

• Clay Preparation• Molding• Drying• Firing

Clay Preparation

• Clay preparation methods may have to accommodate the physical characteristics of the raw material.

• Special provision may have to be made to deal with certain impurities.

• Preparation consists of transforming the clay rock into plastic moldable material.

Molding

• Molding utilizes a drier clay mix, formed into a wedge and thrown into a mold.

• A bow cutter will be used to smooth the top of the brick, and the form will can be released because of a hinged bottom.

Drying

• Water was added during clay preparation to increase workability of the mixture, but in drying it is removed for several reasons.

• First, there will be less cracking in fired bricks with less water content.

• Second, additional fuel is needed, beyond what is used for firing, to dry the bricks in the kiln.

• Proper drying of bricks will involved rotating the bricks for different exposures to ensure even drying rates.

Firing

• Bricks are burnt either in a periodic kiln or a continuous tunnel kiln.

• Stages of burning: Water-smoking and dehydration (drives off the remaining water from clay at 40o to 150o C).

• Temperature of furnace rises to 1000o to 1300o C - Clay transformed to a ceramic material -

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Brick Masonry - Sizes and Shapes

No standard size Normal coursing - 3 bricks = 8” Larger sizes Custom Shapes & Colors

No single standard size available - Size varies Modular Brick: 3 1/2” x 7 1/2” x 2 1/4” (Actual size) Standard Brick : 3 1/2” x 8” x 2 1/4” Engineer Modular : 3 1/2” x 7 1/2” x 2 3/4” Engineer Standard : 3 1/2” x 8” x 2 3/4” Close Modular : 3 1/2” x 7 1/2” x 3 1/4” Roman : 3 1/2” x 11 1/2” x 1 5/8” Norman : 3 1/2” x 11 1/2” x 1 5/8” Brick may be solid, cored, hollow or frogged - This allows even drying of bricks Custom-shaped bricks are often required for building for providing special

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SIZES, GRADES AND TYPES OF BRICKS

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Brick Bonds Structural Bonds Cavity (Veneer) Walls

– Running bond– Stacked bond

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