What is a mortar?
Mortar is defined as the homogeneous mixture of a varying proportion of building materials like cement & sand and sometimes the addition of admixture is required. It is usually named according to binding material used in their preparation. Eg: Cement mortar, lime mortar, etc.
It is classified in several ways i.e based on the binding agent, the proportion of binding agent and aggregate(fine aggregate).
i) Cement mortar
ii) Lime mortar
iii) Lime mortar
iv) Mud mortar
v) Cement-clay mortar
vi) Light and heavy mortar.
vii) Decorative mortar
viii) Fire-resistance mortar
ix) Sound-absorbing mortar
x) Gypsum mortar
DIFFERENT GRADES OF CEMENT MORTAR
|Grade Name||Mix (by Loose Volume)||Compressive Strength at 28 days (in N/mm2)|
|MM 0.7||1||8||0.7 to 1.5|
|MM 1.5||1||7||1.5 to 2.0|
|MM 3||1||6||3.0 to 5.0|
|MM 5||1||5||5.0 to 7.5|
|MM 7.5||1||4||7.5 to above|
– It should be easily workable.
– It should develop adequate strength in tension, compression, and bond for the work.
– It should be durable and not affect the durability of other materials.
– It should set quickly so that the speed of construction is ensured.
– It should be cheap or cheaply available.
– It should bind the bricks or stones to give a tight joint through which water cannot penetrate.
– It should be capable of developing stress.
– The joints form by mortar should not develop cracks and they should be able to maintain their appearance for quite a long time.
Uses of mortar:
– It is used to bind together the brick or stone masonry.
– It is used to fill up a gap between the brick and stone for making wall weather tight.
– It is used to give soft even bed between the different layer of brick and stone masonry for equal distribution of pressure over the bridge.
– It is used in pointing and plastering to protect joints and surface of bricks and stone masonry.
– It is used to fill up the joints of pipes.
– It is used to generate the appearance of the structure.
-It is used to hide the open joints of brickwork or stonework.