There are various types of mortar used in construction, while the mortar is a mixture of cement (or lime), sand, and water.
Mortar prevent excessive cracking because of shrinkage of the paste, while the strength of mortars decreases as the proportion increases.
The mortars absorb carbonic acid steadily from the atmosphere and harden into a solid mass, it is used in masonry construction to fill a gap between bricks or blocks in construction.
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:
Cement mortar is a mixture of cement, fine aggregates i.e. sand, and water is taken in proper proportion, while cement and fine aggregate are properly mixed in required proportions in a 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 after mixing it up and down, a homogeneous paste of cement mortar is formed.
Cement mortar does not require grinding and pounding as it is needed in the lime mortar used for masonry work of stone and bricks.
These mortar is easily used for plastering, repair work, grouting and palling.
Cement mortar requires proper curing to achieve proper strength.
In these types of mortar, the ratio of sand to cement varies from 1: 2 to 6, or volume depending on the strength and importance of the work.
Lime mortar 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 into pits, then water is added to the mixture by 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 mass so that the two grains of sand are not without an interfering film of the binding material.
These types of mortar are used for masonry and plastering work.
The lime mortar is first prepared by grinding or pounding method, then the required quantity of cement is added, then the 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 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 times.
These types of mortar can be used for bedding and thick wall brick masonry work.
Mud mortar types:
Mud mortar is simply a mixture of clay and water 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 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 plasterwork 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 molds for coping, corbels, cornices, etc.
- To serve as a matrix or cavity to hold the coarse aggregates, etc.
Also read: Types of Lime, Types of Cement & Types of Aggregates