What Is Hydraulic Cement?
Hydraulic Cement is a special type of cement that sets very quickly by chemical reaction with water (hydration) and gets solidified with the immersion of water to the finely ground cement. It has the capability to react with water under ambient conditions to form a solidified and water-resistant surface. The hydration reaction in cement results in the formation of a strong solid mass.
Hydraulic cement is nowadays widely used in the construction industry because it possesses properties like non-shrinkable, non-corrosive, and non-rusting.
It is a material commonly used to stop water and sets immediately when exposed to the water. Its sets in 5-10 minutes after adding water content to it.
It is a type of cement that is similar to mortar. It is generally utilized for sealing the structures and in the conditions where structures are submerged in water.
It is made with limestone, gypsum, and clay, which is burned at high temperatures and primarily used to close cracks and leaks in concrete, especially those structures that have weakened with age.
How to Mix Hydraulic Cement?
Before the mixing process of cement, some initial preparation should be done which is discussed below,
Preparation of surface on which cement mix to be applied:
- The surface to be repaired and on which the hydraulic cement mix is to be applied should be clean and dust-free. Oil, grease, dirt & loose particles will prohibit the cement from adhering to the surface adequately.
- It is necessary for the temperature to be maintained between 45 F° (7℃) and 90 F° (32℃) during initial curing since the cement will not be durable on the frozen surface.
- The area should be saturated for 24 hours before applying cement there on the surface.
- Small cracks on surfaces & holes should be enlarged before the application of cement. V-shaped cuts are to be avoided.
Mixing of Hydraulic Cement
A mechanical mixer with rotary blades is recommended for mixing the cement to get a uniform mix.
The mechanical mixer should be saturated properly and drained of extra water before the mixing.
Following the specification and instruction as per the IS 456:2000, the required amount of water is to be added to the dry mix by referring to the grade of concrete. However, one time it begins to harden, more water should not be added to the mix.
- It is recommended that small amounts of cement be mixed at a time since it hardens very quickly and has to be placed within 10-25 minutes.
- The concrete mix should be grinding at a relatively low speed.
Read More: Which Cement is Best for House Construction
Chemical Composition of Hydraulic Cement
The four main chemical constituents of hydraulic cement are listed below:
Tricalcium aluminate (3CaO·Al2O3)
- The chemical properties of cement are produced by the silicates (belite, Alite) whereas the last two chemicals are essential for the liquid phase in the production process inside the kiln.
- Some admixtures (additives) are also required for special properties like greatly reduced setting & curing time, prevention of shrinking, being able to be used underwater construction, etc.
- The working principle of hydraulic cement is based on the process of hydration of cement, which means the cement mix hardens when water is added to it.
- Some chemicals agents present in hydraulic cement state the reactions due to the application of water, which causing the mixture to set & harden very quickly with reducing the curing time of cement mix.
- The properties of these chemical agents make hydraulic cement impervious to water damage and to prevent the repaired surface from chemical attacks.
- Hence, hydraulic cement is more preferable for the construction of structures in close contact with or submerged in a water body or contact with the seawater.
- Another special property of hydraulic cement is its strength against shrinkage and effloresces. Tricalcium silicate & Dicalcium silicate existing in such type of cement cause the following chemical reactions after the addition of water in cement,
Tricalcium silicate+water→ calcium silicate hydrate+other chemical products
Dicalcium silicate+water→ calcium silicate hydrate+other chemical products
- After these reactions, calcium silicate hydrate is the main product, has a network of short fibers that increases the strength of the cement mix greatly and also making the surface water-tight.
Suitability of Hydraulic Cement for Construction
The right kind of cement is to be chosen based on the nature of the construction and development work. Various mixes of hydraulic cement contain changing proportions of chemical components to suit specific necessities.
Hydraulic cement is exceptionally suitable for projects that require a speedy setting and less curing time. However, it just gives a short window of time to work with it before it solidifies, so it is recommended to apply hydraulic cement only for projects that should be done in 10-15 minutes with a moderate amount of cement mix produced at a time.
Its capacity to give strength is monstrous, so utilized for the construction of highly durable structures. The cement is not adaptable, so it must be utilized to offer mechanical support to the structures.
How to Apply Hydraulic Cement
- Before applying hydraulic cement, first clean the surface where repaire is needed.
- The repair surface should be free from Oil dirt or any other contaminant otherwise cement bond will not gain sufficient strength.
- The are of repair should be saturated for 24 hours before its application of hydraulic cement.
- The hydraulic cement should be mixed with water in mechanical mixture to form the uniform mix.
- Add required amount of water as per the manufacturer’s recommendation.
- Any excess water left in mix should be removed before application
- Now, apply hydraulic cement for repair work where it is required.
Precaution While Using Hydraulic Cement
The hydraulic cement mix should be applied on the surface as fast as be possible.
Excessive blending/mixing will cause bleeding and segregation.
Some other admixtures or additives should not be added except if mentioned in the manufacturer’s instructions.
For constructing the underwater structures, hydraulic cement has particularly no other alternative option. Being impermeable to water, it very well utilized in constructing structures that are in steady contact with water.
This type of cement mix doesn’t corrode or rust, hence consequently it holds its strength even when submerged in water. It is also incredibly useful for water-sealing.
Hydraulic Cement Uses
Hydraulic Cement is very useful for the following construction:
- Footings and foundations
- Heavy construction
- Levee walls, sea walls, retaining wall
- Bridges, culverts
- Monolithic concrete houses, concrete block
- Tower structures
- Dams and breakwaters
- Irrigation ditches, filter beds
- Fireproofing structures
- Chimneys and sewer pipes
- Road foundations paved roads, sidewalks
- Tunnels and prison cells
Advantages of Hydraulic Cement
- It is easy to use for any types of work
- Hydraulic cement is set too quickly which helps in achieving desired strength as early.
- This cement is non-shrinkable and does not affect by corrosion.
- Hydraulic cement is waterproof cement, therefore it can be used for underwater construction work.
- Hydraulic cement is one of the economical solutions for repair work compared to other cement products.
- It is widely used in building construction of long lasting concrete repair works.
- It can be used utilized for repair and maintenance of the basement and other concrete repair work.
Disadvantages of Hydraulic Cement
- As hydraulic cement gets hardened quickly, it becomes essential to use it within 10 to 15 minutes of mixing.
- This cement cannot be utilized for the frozen surfaces.
- Hydraulic cement does not have flexible nature, it is only suitable for providing mechanical support.
- It cannot be utilized in areas where the temperature is below 48°F.
Overall, Hydraulic cement is a modern invention that reacts with water chemically to gain strength and form a hardened surface.
Due to its unique properties, it is mostly used across all forms of construction. Hydraulic cement does not shrink or contracts like ordinary cement, and a few mixes even develop solidifying.
FAQs: Hydraulice Cement
Q.1 What is the difference between hydraulic cement and regular cement?
The main difference between hydraulic cement and regular cement is that hydraulic cement able to set in wet condition whereas regular cement essentially required dry condition to set quickly.
Q.2 What is hydraulic cement good for?
Hydraulic Cement is widely used to repair water leaking problem in concrete and masonry walls. This is because hydraulic cement is quickly set even in wet condition.
Q.3 What is Hydraulic Cement?
Hydraulic Cement is a special type of cement that sets very quickly by chemical reaction with water (hydration) and gets solidified with the immersion of water to the finely ground cement.
Q.4 Does hydraulic cement stop water leaks?
Yes. Hydraulic cement made for this purpose to stop water leaks quickly.
Hydraulic Cement Applications
Hydraulic cement used for various application in construction as given below,
Sealing around concrete and masonry structures
Cisterns and fountains
Watch Video: How to Use Hydraulic Cement
This is Protected by disqus
You May Also Like:
- How to Check Cement Quality on Construction Site | How to Check Cement Grade
- Water Cement Ratio – Calculate Proper Amount of Water For Concrete
- High Alumina Cement – Manufacturing, Pros & Cons