Advantages and Disadvantages of Vacuum Concrete

What is Vacuum Concrete?

Vacuum concrete is a type of concrete in which excess water is removed by vacuum pressure after the placement of concrete structural members using vacuum mats connected to a vacuum pump. The goal of vacuum concrete is to increase the strength of the concrete. It is more durable than regular concrete.

Vacuum Concrete Process

1. A large amount of vacuum is present on the top surface of the concrete during the vacuum dewatered concrete procedure.

2. A large amount of water is removed from a specific depth of the concrete during vacuum concrete processing.

3. Vacuum concrete is made by laying porous mats connected by a vacuum pump.

4. The final water cement ratio before setting is then reduced, and the concrete gains strength.

5. Vacuum concrete contains a greater strength capacity, a lower permeability, and a higher durability property, making it a very effective material to use.

The Use of Vacuum Concrete

• The vacuum concrete is mostly used in Hydropower plants.
• A cooling tower is a vacuum concrete application.
• Another use for vacuum concrete is on industrial floors, cold storages, and so on.
• Vacuum concrete is widely used in port and harbour bridges.

Given below advantages and disadvantages of vacuum concrete :

There are numerous advantages to using vacuum concrete, including:

1. One of the primary benefits of vacuum concrete is that its density is higher than that of other types of concrete.
2. The vacuum concrete has a decreasing permeability power, which is also one of its main advantages.
3. A reduction in the water-cement ratio may increase compressive strength by 10 to 50% while decreasing permeability.
4. Because of the high stiffness of this concrete, the formwork and columns of 20 feet in height can be easily removed in 30 minutes.
5. Vacuum concrete has a bond strength that is 20% greater than other concrete.
6. One of the main advantages of this vacuum concrete is its low cost, so it's a good investment.

Disadvantages

• The inherent porosity of the concrete allows water, oil, and grease to seep through, weakening it.
• Joints are required for concrete floors (to accommodate shrinkage, thermal movements, and so on), which can lead to joint breakage and seepage of the aforementioned contaminants.
• Power is used for dewatering, which raises the cost.
• Special tools are required.
• The initial investment is much higher.
• The vacuum dewatered concrete process necessitates the use of skilled labourers.
• It is not well suited to concrete with a water-cement ratio less than 0.4.