Quick Answer
Concrete refers to a construction material made by mixing different ingredients like cement, water, sand, and others. These materials form a hard paste after combining that creates a strong and durable structure.
Did you ever think where our homes get their strength and durability? Although there are various materials that make buildings strong, concrete is one of them. It is the backbone of modern infrastructure across the world. Sounds exciting?
Read on to learn the meaning, types, uses, and more about concrete in this blog post!
What is Concrete?
Concrete is a man-made material that builders use for construction. This solid ingredient makes the structure strong and durable. It is used worldwide because it provides invisible strength to buildings and homes. Concrete also has the ability to withstand heavy loads and harsh weather conditions.
What is Concrete Made of in Construction?
Concrete turns into a solid structure once it is mixed with several ingredients. Below is a list of these ingredients:
Cement
Cement is a fine powder that acts like a binding material in concrete. It forms a thick paste when the water and other aggregates are mixed together. It makes the concrete hard and increases its strength.
Water
Water reacts with cement to make a thick paste. It provides hardness and strength to the concrete. The important point to consider while adding water is to ensure that you add it in the right proportion. Excess water can make your concrete weak.
Fine Aggregates
Fine aggregates like sand and crushed stones make the concrete highly compact and dense. You can use them to fill the gaps between coarse aggregates. What’s more? They help you mix the ingredients with less effort.
Coarse Aggregates
Coarse aggregates are used to provide high strength to the concrete. These aggregates include larger particles such as gravel or crushed rocks. The strength of the concrete also depends on the size, shape, and quality of the coarse aggregates.
Tip: You can consult with J.K. Cement experts for on-site assistance.
What is the Concrete Mix Ratio?
Concrete mix ratio refers to the proportion of ingredients used to make concrete. The table below highlights the proportion for nominal mix concrete:
| Grade of Cement | Total Quantity of Dry Aggregates by Mass per 50kg of Cement to be taken as the sum of the individual masses of Fine and Coarse Aggregates, kg, Max | Proportion of fine aggregate to coarse aggregate (by mass) | Quantity of water per 50 kg of cement |
|---|---|---|---|
| M5 | 800 | Generally, 1:2, but subject to an upper limit of 1:1:5 and a lower limit of 1:2:5. | 60 |
| M7.5 | 625 | 45 | |
| M10 | 480 | 34 | |
| M15 | 330 | 32 | |
| M20 | 250 | 30 |
Note: Adjust the ratio of the fine to coarse aggregates from the upper to lower limit progressively. This is because the grading of the fine aggregates becomes finer and the maximum size of coarse aggregate becomes larger. Graded coarse aggregate shall be used.
What Are the Different Types of Concrete?
The choice of the type of concrete depends on your specific construction needs. It is influenced by different factors like strength, durability, weight, and the method of construction. Some of the main kinds of concrete are given below:
Plain Cement Concrete
It is the basic form of concrete that is generally used for the flooring and pavements. It does not contain steel reinforcement and is not suitable for heavy loads. While the compressive strength of plain concrete cement is good, tensile strength is very low. The best part? It is easy to mix and available at a budget-friendly rate.
Reinforced Cement Concrete
This type of concrete has better tensile strength and offers high durability. It is primarily used in the construction of large projects like residential or commercial buildings, bridges, and dams. The ratio of cement in reinforced concrete is strong in compression. However, steel is strong in tension.
Ready-Mix Concrete
Ready-mix concrete is made instantly in batching plants for the construction of large projects. The builders receive it fresh and in usable form at the site. It not only helps in saving time but also reduces the labor and material cost.
Pre-Cast Concrete
This type of concrete is manufactured in a specific environment in the factory. Further, it is transported to the construction site for installation. It is generally used to build railway sleepers or precast walls and slabs. The greatest feature of pre-cast concrete is that it helps in fast construction.
High-Mix Concrete
It is not an ordinary type of concrete but one with higher compressive strength. It is capable of managing heavy loads and comes with long durability. The bridges or skyscrapers that you see are built of high-mix concrete.
What Are the Properties of Concrete?
Given below are some of the properties of concrete:
High-Compressive Strength
Concrete has an ability to manage the heavy loads without crushing or failing. Most importantly, it helps the columns and foundations in providing support to buildings. It outperforms during the compression, which is highly important.
Durability
Another property of concrete is that it is highly durable and requires low maintenance. Whether it is weathering, water, or environmental effects like heat or rain, concrete withstands all the conditions. What does this mean? It means that it not only increases the lifespan of the structures but also makes the construction cost-effective.
Workability
It is easy to mix and shape the fresh concrete into different forms and sizes. Hence, it allows you to create complex designs and structures before it becomes hard. This is how the engineers and architects create different shapes and structural elements.
Fire Resistance
Concrete is a non-combustible material that does not burn or release harmful gases when exposed to fire. You can keep it at high temperatures for a long period of time. The strength of the concrete will remain the same. As a result, it acts like a shield in case of fire in the buildings.
What is the Difference Between Concrete and Cement?
The difference between the concrete and the cement is given in the table below:
| Basis | Cement | Concrete |
|---|---|---|
| Definition | It is a thin powder that behaves like a binding material. | It is a composite construction material made up of several ingredients, such as water, cement, sand, and other aggregates. |
| Usage | It is not used as a separate product in any type of construction. | It is widely used for large constructions like dams, bridges, and others. |
| Strength | It does not provide strength to the structures. They can crack down without concrete. | It provides extensive strength to the structures because it is formed after mixing multiple ingredients. |
| Cost | It is expensive per unit weight in comparison to concrete. | It is cost-friendly in bulk due to additional aggregates. |
| Durability | It provides less durability on its own. | It is highly durable and longer-lasting than cement. |
What Are the Uses of Concrete in Construction?
If you see any building and wonder about its modern and strong structure, that’s concrete working for the modern infrastructure. Given below are some common uses of concrete in construction:
- Foundations and footings
- Beams, columns, and slabs
- Roads and pavements
- Bridges and dams
- Residential and commercial buildings
How Much Time Does Concrete Take to Settle and Cure?
Concrete becomes hard by setting first and then is followed up by the curing process. The initial setting happens within 30 minutes to 2 hours, and the final setting occurs in 6 to 10 hours. At this stage, the concrete is still weak and must be cured to increase its strength through hydration. The curing process results in 60-70% stronger concrete in 7 days and full-design strength in 28 days. This step is important as it prevents cracks and maintains durability.
What Are the Grades of Concrete?
The grades of concrete are divided into 3 different categories and used depending on the type of work. These grades include:
Ordinary Grade
This ordinary grade is generally used for non-structural constructions. It is because they are low in strength and do not provide maximum durability.
| Grade | Strength | Typical Use |
|---|---|---|
| M 5 | 5 MPa | Leveling |
| M 7.5 | 7.5 MPa | Bedding for foundation |
| M 10 | 10 MPa | Pathways, leveling course |
| M 15 | 15 MPa | Plain cement concrete |
Standard Grade
This grade of concrete is not only used for construction but is also suitable for reinforced cement concrete (RCC). The proportions of standard-grade concrete require scientific calculations for better strength and durability.
| Grade | Strength | Typical Use |
|---|---|---|
| M 20 | 20 MPa | Residential buildings and slabs |
| M 25 | 25 MPa | RCC structures including beam, slabs, and columns |
| M 30 | 30 MPa | Heavy-duty structures |
High-Standard Grade
The high-standard grade is usually used for constructions that require high strength and durability. They come with properties like strength, workability, and resistance to chemicals.
| Grade | Strength | Typical Use |
|---|---|---|
| M 35 | 35 MPa | Bridges and commercial buildings |
| M 40 | 40 MPa | High-rise structures such as commercial buildings |
| M 45 | 45 MPa | Pre-stressed concrete |
| M 50 & above | 50+ MPa | Mega projects like dams and flyovers |
What Are the Common Mistakes To Avoid While Mixing the Concrete?
The primary win in the construction process is to mix the concrete in the right proportions. Below are some additional tips that you must keep in mind even before mixing the concrete:
- Avoid using excess water, as it can result in shrinkage and cause cracks after the drying process.
- The quality of the aggregate material should be appropriate. Low-quality ingredients can influence the final strength.
- Ensure that you mix the concrete properly. This is because uneven distribution of ingredients can create weak zones.
- Using pure water is another important factor to keep in mind. Water containing salts or chemicals can interfere with the hydration process of the cement.
Frequently Asked Questions
1. What is the difference between cement and concrete?
Cement is a fine powder, whereas concrete is a composite material made from cement and other ingredients. Cement cannot build structures alone, but concrete provides strength. This is the reason why builders mostly use concrete for construction.
2. Which is stronger, cement or concrete?
Concrete is stronger than cement. This is because different materials like cement, sand, aggregates, and others are mixed together to form a concrete. Hence, it provides bulk and load-bearing capacity to the structures.
3. What is M20 concrete?
M20 concrete is a grade that is commonly used for construction. The mix ratio of M20 concrete is 1:1.5:3, i.e., cement:sand. It provides the compressive strength of 20 MPa after the curing process of 28 days.
4. How long does concrete take to cure?
The actual curing time for concrete may vary depending on conditions. However, it usually takes up to 7-28 days to cure properly.
5. What are the main types of concrete?
The main types of concrete are:
- Plain cement concrete (PCC)
- Reinforced cement concrete (RCC)
- Ready-mix concrete
- Precast concrete
- High-strength concrete
