There are various types of mortar used in construction, mortar is a mixture of cement (or lime), sand and water.
If we use cement as a binder it will be cement mortar and if we use lime it will be lime mortar.
Modern mortars are mixtures of cement and sand in various strengths, hydrolyzed lime can also be added in small quantities.
Different types of mortar used for plastering:
This mixture of cement, fine aggregate i.e. sand and water is taken in proper proportion.
Cement and fine aggregate i.e. sand are well mixed in required proportions in dry state on watertight platforms.
In the dry state, the mixture is made up and down with the help of a phawrah.
Then the water is added to this mixture and again after mixing it up and down, a homogeneous paste of cement mortar.
Cement mortar does not require grinding and pounding as it is needed in lime mortar.
It is used for masonry work of stone and bricks.
Also,it is easily used for plastering and repair work.
It is also used for grouting and palling.
Cement mortar requires proper curing to achieve proper curing.
In these types of mortar, the ratio of sand to cement varies from 1: 2 to 6, or by volume depending on the strength and importance of the work.
It is a mixture of lime, sand and water in appropriate proportions prepared in two ways such as grinding and pounding.
The grinding method of preparing lime mortar is more efficient than pounding.
In the pounding method, lime and sand are mixed in a dry state and the mixture is then placed in pits.
Water is then added to the mixture then repeatedly poured up and down.
The required amount of water is added at equal intervals, when the mortar mass becomes continuous, it is taken out of the pits to be used in masonry work.
In the grinding method, grinding mills are used to prepare lime mortar on a large scale, the following are the two main items of grinding and pounding lemon mortar as follows:
- To crush unsalted lime particles.
- To create an intimate mixture of the whole mass so that the two grains of sand are not without an interfering film of the binding material.
Lime mortar types are used for masonry and plastering work.
Composite mortar or lime-cement mortar:
The lime mortar is first prepared by grinding or pounding method, then required quantity of cement is added and then complete mass is thoroughly turned up and down so as to get a homogeneous paste of gauged mortar.
Thus composite mortar or gauged mortar is a mixture of lime mortar and cement taken in appropriate proportion.
Cement is added to lime mortar to increase the strength of lime mortar, the process of adding the cement into lime mortar is termed as gauging.
The gauging process is useful to improve the quality of the lime mortar and also to achieve early strength.
Due to this gauging process, the lime mortar becomes more strong, economical and dense, the proportion of cement to lime by volume is about 6 to 18.
Gauged mortar can be used for bedding and for thick wall brick masonry work.
Mud mortar types:
It is simply a mixture of clay and water and used for cheap houses.
In villages, the use of mud mortar is very common for masonry and plastering work.
For making mud mortar, red soil or yellow soil having more plasticity and low shrinkage limit should be used, black cotton soil is never be used for making mud mortar.
Functions of various types of mortar:
- To tie building materials such as bricks and stones into a solid mass.
- For pointing and plaster work on exposed surfaces of masonry.
- Also, to create a uniform and soft bed layer for construction units.
- To make pipe joints.
- To improve the general appearance of a structure.
- Also, to prepare the moulds for coping, corbels, cornices, etc.
- To serve as a matrix or cavity to hold the coarse aggregates, etc.
It is used to bond masonry or other structural units.