Thursday, May 28, 2020

Bonds In Bricks - Brick Masonry

Bonds In Bricks - Brick Masonry

Bonds of the bricks can be defined as the arrangement of the bricks so as the vertical joints may not come above each other, which will result in decreasing the strength of the wall.

These Bonds helps to reduces the stresses coming to the brickwork , making it uniformly distributed to the surroundings.

To break the continuity of vertical joints closers or bat are provided in alternative courses.

Lets take and example - Put few books one above the other, next to it place same number of books so as the joints will come at the same line. Once you apply the force , it will be easier to remove them.

You will get a better idea by looking to the image.

Now same we arrange the books similar to the Bonds in which the vertical joints may not come above each other.

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From above we can see, if we apply force there will not be effect of shear as much as in example 1
That is the reasons we apply bonds in Brick masonry.

Types of Bond

  • Stretcher Bond.
  • Header Bond.
  • English Bond.
  • Flemish Bond.

Stretcher Bond. (running bond)

Long narrow face of the brick is called as stretcher. The bond is created when bricks are laid with only their stretchers showing, overlapping midway with the courses of bricks below and above.
This type of Bond is only used in 4 inches walls, which can be termed as half brick thickness walls. 

This bond is not as effective if we compare it with full length brick wall 

The walls in strecher bonds are not stable enough for long span and height. Toovercome the problem supportings are been provided such as columns at regulat intervals. Due to which we usually provide columns at every 4m and coping(a rcc of 75mm-100mm) at 1.2-1.5m height.

These are commonly used as partition, reinforcement or steel outer face structures or boundary walls

Header Bond (Spanish bond) or (heading bond)

Headers are shorter square face of the brick which measures 9cm x 9cm . These bonds are very common bond for bearing walls. They consists of header bricks, which are set in rows with an offset of ¾ of a brick which is determined as a quoin brick in alternating courses.

 In header bonds, all the bricks at each course are laid as headers of the bricks facing wall.

These bonds are used in full brick thickness wall measuring 230mm.

In header bonds, all the overlaps are arranged in such a manner that the overlap should come as equal to half width of the brick. To accomplish this, three quarter brick bats are used in alternate courses which are named as quoins.

English Bond

English bond in brick masonry are the arrangements in which one course is made of strechers and above it the other course in made of headers of the bricks, So we can say that , they are alternative arrangements of headers and stretcher bonds.

Quoin closer are provided at the beginning and the end of headers to break the continuity of vertical joints.
Quoin close is a brick which are cut in lengthwise in 2 half's after which they are used as corners in brick walls.

Advantages of English bond

  • The strongest bond
  • This bond maximizes the strength of wall
  • Pattern on the face of the wall shows distinctive courses of headers & stretchers.

Flemish Bond (Dutch bond)

They are laid alternate headers and stretchers in a single course. The second course of brick is laid such that header lies in the middle of the stretcher in the course below. The thickness of wall use to be of 1 full brick i.e 230mm.

The alternative course in this bond are started with a header from corner of the wall.
  • Alternate headers & stretchers shows decorative pattern at the face of wall.
  • To break the continuity of vertical joints queen closers are provided after every queen headers at alternative courses.
  • Brick bats are used when required.

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