Types of Concrete Used in Construction
Concrete is a construction material composed of cement, fine aggregates, and coarse aggregates mixed with water. Concrete is used for the construction of foundations, columns, beams, slabs, and also other load-bearing components.
There are different kinds of binding material is used other than cement-like bitumen for asphalt concrete which is used for road construction.
Types of Concrete
There are many different types of concrete. Properties and uses of different types of concrete are explained briefly,
1. Normal Strength Concrete
This type of concrete blends all the basic components, cement, sand, and aggregates using different ratios as per required strength. The strength of this type of concrete will vary from 10 MPa to 40MPa. It takes around 30 to 90 minutes to set, but this depends on the weather conditions at the concrete site and the cement’s properties.
It’s generally used for pavements or buildings that don’t require high tensile strength. It is not very good for several other structures as it is quite bad at withstanding stresses creates by vibrations, wind loading, and so on.
2. Plain Cement Concrete (PCC)
In plain cement concrete (PCC), it is poured without the use of any type of reinforcement. This is used when the structural member is subjected only to the compressive forces and not bending. This is another concrete that uses the typical mix design of 1:2:4 with its ingredients of cement, sand, and aggregates.
It can use to make sidewalks or buildings where there is not a high need for tensile strength. It bears the same problems as normal strength concrete– it doesn’t stand up effectively to vibrations or wind loading. The toughness evaluation of this kind of concrete is quite satisfying.
3. Reinforced Cement Concrete (RCC)
Reinforced Cement Concrete (RCC) is one of the most important concrete types and is widely used in the construction industry. In this concrete type, steel in different forms is used as reinforcement to give very high tensile strength. The steel reinforcement used in the concrete can be in the form of rods, bars, or in the form of meshes. Now fibers are also produced as reinforcement.
It is because of the combined activity of plain concrete which is having high compressive strength and steel which is having high tensile strength.
It makes sure the maximum bond between the reinforcement and the concrete while the setting and hardening process.
These reinforcements resist tensile forces while the concrete itself resists compressive forces. They develop a strong bond and therefore, both materials resist various applied forces.
4. Precast Concrete
Many structural components can be made and cast in the manufacturing unit or mold at the site as per the specifications, and bring to the site from the manufacturing unit at the time of assembly. These types of concrete units are called precast concrete. Precast concrete is used for precast poles, fence posts, concrete lintels, staircase units, concrete blocks, and precast walls.
The benefit of using precast concrete is its quick assembly. Because the units are made in a factory, they are of very high quality. The current trend in the construction field is to move increasingly to prefabricated concrete units in building construction.
5. Prestressed Concrete
Most of the major concrete projects use prestressed concrete units. It is a special type of reinforced concrete in which the reinforcement bars or tendons are stressed before the actual use of the concrete.
When the concrete is mixed and placed, these bars are positioned at each end of the structural unit where they are used. When the concrete sets and hardens, this unit is put into compression. This procedure makes the lower section of the reinforced concrete also stronger against tension.
This technique requires heavy tools and equipment and also need experienced labor. Usually, prestressed units are created and assembled on-site. Prestressed concrete is used to construct bridges, heavy-loaded structures, or roofs that have long spans.
6. Lightweight Concrete
Any type of concrete that has a density less than 1920 Kg/m3 is identified as lightweight concrete. This type of concrete is developed by using lightweight aggregates. Aggregates are, components that contribute to the density of the concrete.
Different types of aggregates that are used in the making of lightweight concrete include natural materials like pumice and scoria, artificial materials like expanded shales and clays, and processed materials like perlite and vermiculite.
The most important thing about lightweight concrete is its very low thermal conductivity. The lightweight concrete is used for the protection of the steel structures, construction of the building blocks, and also used for the construction of the long-span bridge decks.
7. High-density Concrete
High-density concrete has a quite particular purpose. In this concrete type, the density ranges 3000-4000 Kg/m3, and also this type of concrete is called heavyweight concrete. These types of concrete are made by using high-density crushed rocks as coarse aggregates.
One of the most commonly used heavy-weight aggregates is Barytes that contains barium sulfate. It is commonly used in the construction of atomic power plants. The heavyweight aggregates used in the production of high-density concrete benefits the structure to resist radiation.
8. Air-Entrained Concrete
Some types of concrete have plenty of air cells in every cft of concrete. These little air cells soother the inner pressure on the concrete. They give little boxes where water can increase when it freezes.
The air is entrained in the concrete by adding different foaming agents. Some examples of air-entraining agents are resins, alcohols, and fatty acids. The volume of air hence, entrained may vary between 3-6 percent of the concrete. Mostly all concrete use in freezing conditions.
9. Ready Mix Concrete
This concrete type is prepared in concrete plants and delivered with the help of transit mixtures. When the vehicles reach the project site, the concrete can be used immediately since it does not need further treatment. Ready-mix concrete is a specialty concrete that is mixed based on specifications and mixed designs with great precision.
The plant location should be at an adjustable location so that the concrete can be supplied before the set time. If the site is too far from the concrete plant then retarding agents are to be used to increase the initial setting time of concrete. Ready-mix concrete is preferred to concrete blended on-site because the ready-mix concrete has higher accuracy. Ready-mix concrete can be used for buildings, roadways, walls, and many other works.
10. Polymer Concrete
Polymerization is a procedure of conversion of monomers into polymers. In polymer concrete, the aggregates will be bound with the polymer instead of cement. The processing of polymer concrete will help in the reduction of the volume of voids in the aggregate. This will therefore reduce the quantity of polymer that is required to bind the aggregates used.
Currently, four types of polymer concrete materials are available,
- Polymer impregnated concrete
- Polymer cement concrete
- Polymer concrete
11. High Strength Concrete
High-strength concrete is concrete with a strength of over 40 N/mm2. This increased strength is achieved by decreasing the water-cement ratio even lower than 0.35. High strength concrete is used to achieve some special properties in concrete like high strength, low shrinkage, self compaction, high fire resistance, etc. The high-strength concrete shows less performance in terms of workability which is an issue.
The materials used in the high strength concrete are the same as ordinary concrete but to make high strength concrete add cementing materials like silica fume, fly ash, blast furnace slag, etc, and Superplasticizers if required.
12. Self Consolidated Concrete
These types of concrete are compacted by their own weight, are regarded as self-consolidated concrete. This type of concrete does not require any vibration or compaction. The workability of concrete is always high in this type. That is the reason it is also known as flowing concrete. Self-consolidating concrete works great in the areas where there is heavy reinforcement. This type of concrete is commonly used in pile foundations.
13. Shotcrete Concrete
Shotcrete is concrete created similarly to ordinary concrete, however, the difference is that they are laying in a different way.
This type of concrete is placed with the help of high air pressure with nozzles. The advantage of this technique is that the compaction and laying of concrete will be done at the same time.
14. Pervious Concrete or Permeable Concrete
Pervious Concrete or Permeable concrete is created in such a way that the water can be passed in it. They have about 15% to 20% voids to ensure that the water can pass in it. This is one of the most common kinds of concrete used to build roads and pavements. It is created to manage the problems of stormwater overflow and swimming pools water and puddles on roadways or airport runways.
It is made up of a combination of cement, water, and coarse aggregates. It has no sand, which develops an open-scale, permeable structure. This permits water to pass through the layers more easily.
15. Vacuum Concrete
In this type, an additional amount of water is added to the concrete mix, and after that, the mixture is poured into the formwork. The excess water is then taken out from the concrete with the help of a vacuum pump without waiting for the concrete sets. It is called vacuum concrete.
This method is used to achieve the strength of concrete early. It can achieve compressive strength within the period of 10 days as compared to 28 days of normal concrete.
16. Pumped Concrete
Exactly how the concrete blends, used in the flooring of a very high building are? Obviously, it is pumped concrete. Pumped concrete is very workable, so it can be conveyed easily via a pipe to an upper floor. This pipe will be a flexible or inflexible hose that discharges the concrete to the required area.
It is a reliable, effective, and economical way to use concrete and is often the only way that concrete can be placed in certain locations. Very fine aggregates are used in pumped concrete. The finer the aggregate used in the mix, the freer the concrete flows from the pipe.
17. Stamped Concrete
Stamped concrete is a type of concrete, textured and colored to provide the image of patterns looking like bricks, slate, stone, and wood. It provides a more affordable and sustainable substitute for bricks or natural stone. Stamped concrete is even a nice improvement from laying lackluster typical concrete in your home.
Stamped or ornamental concrete is normally tinted by two techniques, either by the use of integral coloring procedure or by using a color hardener. In the past method, color is blended into the concrete to give it a natural shade, while in the recent, color is applied on top of concrete during the beginning of the finishing process.
Stamped concrete has mid-range compressive strength and if well maintained it’s perfect for a minimum of 25 years. It is really convenient and can be used for different ornamental or realistic uses in residences. Popular uses of stamped concrete provide flooring alternatives for swimming pool sides, outside kitchen areas, specialized lawns, counter-tops, driveways, and patio areas.
This concrete uses lime instead of cement, along with lightweight aggregates like glass fiber or sharp sand. It’s mainly used for the construction of floors, vaults, and domes. Limecrete has several environmental advantages because it is so conveniently cleaned and is renewable. It can also be used with shining floor heating.
19. Asphalt Concrete
Asphalt concrete is a combination of aggregates and asphalt. This is a form of concrete frequently used on roads, airport runways, highways, parking areas, and sidewalks. Asphalt is a dark mineral composed of a mixture of hydrocarbons called bitumens. The different mixtures of asphalt are used for different purposes.
20. Roller Compacted Concrete
This concrete is usually utilized as a filling material. They don’t have a greater strength value. They are lean concrete and are compacted with the help of weighty methods, like heavy rollers. Quite less quantity of cement is used in this kind of concrete.
21. Rapid Strength Concrete
These concretes will attain strength some hours after their manufacture. This type of concrete is mostly used in underwater construction and in the repairing of roads. Because its setting time is really less. They are also utilized in building construction, where the work should be done quickly.
22. Glass Concrete
When recycled glass is used as an aggregate in the concrete, this kind of concrete is called Glass Concrete.
This type of concrete is used when the aesthetic look is an important element in the design of the concrete.
Commonly utilized in the large-format slabs found in flooring or on decorative façades, this concrete can have shining or colored glass installed during the blending process.
23. Fiber Reinforced Concrete
This type of concrete where fibers 10 to 20 microns in diameter and 10 to 50 mm in length is used is called fiber reinforced concrete.
Fiber improves resilience, tensile strength, flexibility, and other qualities.
The fibers might be various products like steel, polymer, glass, carbon, and can be natural fibers like coconut fiber.
Some sort of fibers reacts with the cement, special treatment needs to be taken while utilizing them. It has been used mostly as overlays for pavements in bridges, airports, and industrial floors.
Fiber-reinforced concrete can also be used in places where increased resistance to cracking is required.
24. Fly Ash Concrete
Concrete using fly ash is called fly ash concrete. Fly ash is gotten from coals. Fly ash can be used to change fine aggregates or cement or to change partially both.
Fly ash improves workability in the fresh concrete and durability and strength in set concrete.
The fragments of fly ash should be finer than cement particles.