Bonding in Brickwork
Bonds in brick work means method of arranging the bricks in courses so that individual brick units are tied together and the vertical joints of the successive courses do not lie in same vertical line.
Purposes of Brick Bonding
- Obtain maximum strength whilst distributing the loads to be carried throughout the wall, column or pier.
- If bonds in brick work are not arranged properly, then a continuous vertical joint will result. This is called an unbonded wall having little strength and stability. (See fig. below)
- To ensure lateral stability and resistance to side thrusts.
- To create an acceptable appearance.
Rules for Bonding in Brickwork
For getting good bond, the following rules should be observed.
The bricks should be of uniform size. The length of the brick should be twice its width plus one joint, so that uniform lap is obtained. Good bond is not possible if lap is non-uniform.
The amount of lap should be minimum ¼ brick length along the length of the wall and ½ brick length across the thickness of the wall.
Avoid using brick bats unless it is necessary or required in special locations.
In alternate courses, the center line of header should coincide with the center line of the stretcher, in the course below or above it.
The vertical joints in the alternate courses should be along the same vertical axis.
The stretcher should be used only in the facing; they should not be used in the hearting. Hearting should be done in headers only.
It is preferable to provide every sixth course as a header course on both the sides of the wall.
Use of raked and other joints that provide horizontal water tables should be avoided. Concave and weathered joints should be provided.