Mortar: Essential Types, Mixing Techniques, and Construction Applications

What Is Mortar?

Mortar is an intimate mixture of inert cementing material, fine aggregates and water. It’s a workable paste which hardens to bind blocks such as brick, stone, concrete block, etc. It’s mainly used for binding blocks and plastering the masonry surface. Mud, lime, cement or a combination of these three is used as cementing material. Sand is used as a fine aggregate in mortar.

There are different types of mortars in Civil Engineering. They are-

Cement Mortar
Lime Mortar
Mud Mortar
Special Mortar

How to Make Mortar

At first, we need to measure the quantities of cement and sand. For the essential mix, we use 3 parts sand to 1 part cement. The right amount of water is needed for mixing purpose. One bag mortar should be mixed with three gallons of water to maintain proper consistency. Proper use of sand and mortar. Fine sand is preferable for preparing the cement mortar.

We require to use lime as an additive material. Lime makes the interconnecting bond stronger. Lime is specifically used in high wind area. We need to remember that if we add lime in the mortar, it will set more quickly.

How to Mix Mortar

There are two types of mixture exist in the civil engineering field. They are-

Hand Mix
Machine Mix

1. Hand Mix

At first, we stack an amount of sand and the required number of cement bags. Pile of sand should like a small mountain. Then cut the cement bag and dump the cement on the sand by the trowel or hoe. Next, we need a hoe or a shovel to mix vigorously.

We need to remember that mix is distributed uniformly and even coloured. If the mixture is not suitably mixed, then the consistency will be affected.

After that, we form a crater by hoe or shovel and pour water into it. By using a hoe or shovel pick up the dry mix from the outside edge and put it into the middle portion. Sometimes we need to add extra water to the mix. Finally, mix the mixture for 3 to 5 minutes and let it for another one minute.

2. Machine Mix

At first, we need to wash out or wet the mixer, wheelbarrow and buckets by water. Then, insert the dry materials like sand, stones and cement into the mixer and start mixing.

Finally, we add water into the mix and mix appropriately for a few moments. If there is a lack of water in the mixture, then we add some water. So, this is the entire process of Machine Mix of mortar.

What Is Mortar Made Of

There are commonly four types of mortars are used. So, the materials are also different for different kinds of mortar. They are following-

Cement Mortar
Lime Mortar
Mud Mortar
Special Mortar

#1. Cement Mortar

Cement (as binding material)
Sand
Water

#2. Lime Mortar

Lime, fat lime or hydraulic lime (as binding material)
Sand, surki or cinder
Water

#3. Mud Mortar:

Clay
Sand
Water
Sometimes fibrous material like cow dung is added, and some amount of (about 5%) hydrated lime and bitumen is added.

#4. Special Mortar

There are many types of special mortar, which are as follows

Cement Clay Mortar
Gauged Cement Mortar
Decorative Mortar

#a. Cement Clay Mortar

Cement
Clay
Water

#b. Gauged Cement Mortar

Cement
Lime
Water (ratio should be 1:1:6, 1:2:9 or 1:3:12)

#c. Decorative Mortar

Coloured Cement (instead of ordinary cement)
Sand
Water

Uses of Mortar

There are several uses of mortars. Those are following-

Uses of Cement Mortar
Uses of Lime Mortar
Uses of Mud Mortar
Uses of Special Mortar

1. Uses of Cement Mortar

To bind masonry blocks like bricks, stones, cement blocks, etc.
To give a neat and smooth finish to the wall and concrete surface.
Plastering works in slabs and walls.
To fill joints and cracks.
To give pointed joints to masonry works.
Act as a filler material in stone masonry.
Act as a filler material in Ferro-cement works.

2. Uses of Lime Mortar

Fat lime mortar is used for plastering.
Hydraulic lime mortar is used for construction works.
This mortar is used where lime is locally available.

3. Uses of Mud Mortar

Use to construct monolithic structures.
Masonry works like walls, wattle, daub, etc.
Use to construct flat roofs, vaults, domes, etc.

4. Uses of Special Mortar

Use as water resistance material.
It has a predetermined setting time.
Use as a decorative finish to the wall surface.

Mortar in Construction

In civil engineering construction, mortar is one of the most important things.

Cement Mortar in Construction
Lime Mortar in Construction
Mud Mortar in Construction
Special Mortar in Construction

1. Cement Mortar in Construction

To prepare cement mortar, we follow these charts to combine cement and sand for various works.

Works	Cement: Sand
Masonry Works	1:6-1:8
Plastering Works	1:3-1:4
Plastering Concrete	1:3
Pointing	1:2-1:3

Compressive strength of mortar is another crucial point. Here is the chart of compressive strength of mortar for different proportion-

Cement: Sand	Compressive Strength in N/mm²
1:3	10 N/mm²
1:4	7.5 N/mm²
1:5	5.0 N/mm²
1:6	3.0 N/mm²
1:8	0.7 N/mm²

2. Lime Mortar in Construction

In ancient Egypt, there was the first use of lime mortar to construct the pyramids, temples, homes, etc.
In Mohenjo-Daro, there was actively the use of lime concrete.
There was also widespread use of lime mortar in Rome & Greece.

3. Mud Mortar in Construction

Nowadays, mud mortar is not used in the construction because of its insufficient strength, but in rural areas, there is still use of mud mortar.

4. Special Mortar in Construction

In current civil engineering construction, there is a massive roll of special mortar. Some of those are-

Use as water resistance material.
It has a predetermined setting time.
Use as a decorative finish to the wall surface.
It’s also used as a fire-resistant mortar.

So, this is the enormous role played by mortar in civil engineering construction.

FAQs About Mortar in Civil Engineering

What Is Mortar and What Is It Used for in Construction?

Mortar is a mixture of cementing material (such as cement or lime), fine aggregates (usually sand), and water. It is used primarily to bind together building blocks like bricks, stones, and concrete blocks, as well as for plastering masonry surfaces.

What Are the Different Types of Mortars Used in Civil Engineering?

The main types of mortars used are:

Cement Mortar
Lime Mortar
Mud Mortar
Special Mortar (includes variations like cement clay mortar and decorative mortar)

How Is Mortar Mixed for Construction Purposes?

Mortar can be mixed by hand or using machines:

Hand Mixing: Involves stacking sand and cement, creating a mound, adding water gradually, and mixing vigorously with a hoe or shovel.
Machine Mixing: Dry materials (sand, stones, cement) are added to a mixer, followed by water, and mixed until uniform consistency is achieved.

What Are the Key Properties and Uses of Different Types of Mortars?

Cement Mortar: Used for masonry works, plastering, filling joints, and as a filler in stone and Ferro-cement works.
Lime Mortar: Includes fat lime for plastering and hydraulic lime for construction where lime is locally available.
Mud Mortar: Historically used for monolithic structures, walls, and roofs in rural areas.
Special Mortar: Used for water resistance, decorative finishes, and fire resistance in construction.

How Do the Proportions of Cement and Sand Affect the Strength of Mortar?

The ratio of cement to sand determines the compressive strength of mortar. For instance, a higher ratio of cement to sand results in stronger mortar, suitable for different construction applications.

What Are the Historical and Modern Applications of Mortar in Construction?

Historically, mortar, especially lime mortar, has been used in ancient civilizations like Egypt and Greece for monumental constructions. Today, modern mortars cater to a wide range of construction needs, from residential to commercial projects.

What Are Some Tips for Ensuring Quality Mortar in Construction Projects?

Ensure proper mixing proportions (cement to sand ratio).
Use appropriate curing methods to enhance strength and durability.
Follow manufacturer guidelines for additives and water content.

How Does Mortar Contribute to Sustainable Construction Practices?

Mortar, especially lime and mud mortar, can contribute to sustainable construction by utilizing locally available materials, reducing carbon footprint, and providing thermal mass benefits.

What Are Some Challenges Associated with Mortar in Construction?

Challenges include maintaining consistency in mixing, ensuring adequate curing to prevent cracking, and adapting mortar mixes to specific environmental conditions and building requirements.

What Future Trends Are Expected in the Use of Mortar in Civil Engineering?

Future trends may include advancements in mortar additives for enhanced performance, increased use of sustainable materials, and innovations in mortar application techniques for efficiency and durability.