Hydrophobic cement, also known as hydrographic cement, gets its name from the combination of “hydro,” meaning water, and “phobic,” meaning against. This type of cement is produced by grinding portland cement clinker with a film-forming substance like oleic acid. The purpose of this process is to slow down the rate of deterioration of the cement when it is stored under unfavorable conditions.
The film-forming substance used in the production of hydrophobic cement creates a layer on the surface of the cement particles that repels water. This layer prevents water from penetrating the cement, making it ideal for use in structures that are exposed to moisture or humidity. Hydrophobic cement is widely used in the construction industry for various applications, including underground construction, marine structures, and structures in areas with heavy rainfall.
One of the significant advantages of using hydrophobic cement is its ability to resist water penetration, which makes it highly durable and long-lasting. This type of cement is also less prone to cracks and reduces the chances of efflorescence. Additionally, hydrophobic cement has a faster setting time, which allows for quicker construction.
However, hydrophobic cement also has some disadvantages. It is more expensive than regular cement, and its production process requires special equipment and expertise. Moreover, it is not suitable for all types of construction projects and should only be used where there is a high risk of moisture penetration.
As with any construction material, safety precautions must be taken when handling hydrophobic cement. Protective gear such as gloves, masks, and safety glasses should be worn to avoid skin or eye irritation. It is also essential to follow the manufacturer’s instructions carefully to ensure that the cement is used correctly and safely.
Fig 1: Water resistant concrete made of Hydrophobic cement.
Manufacture of Hydrophobic Cement
The manufacturing process of this particular type of cement is similar to that of Portland cement. Clinkers are produced during the cement manufacturing process and are then ground with a water-repellent film substance, such as Oleic Acid or Stearic Acid. These chemicals form a layer on the cement particles, preventing water from mixing and initiating the hydration process during transportation or storage.
However, when the cement is mixed during the construction process, the layer of water repellent is broken due to the intense agitation, thus allowing the hydration process to take place. Despite the presence of the water-repellent layer during storage and transportation, it does not affect the quality of the cement as it breaks down during mixing, thereby enabling the cement to perform its intended function.
Properties of Hydrophobic Cement
Table 1: Properties and their values of Hydrophobic cement.
| Properties | Value |
| Fineness | 350 m2/kg |
| Soundness | |
| Lechatelier (mm) | 10mm |
| Autoclave | 0.8 % |
| Setting Time | |
| Initial Setting | 30min |
| Final Setting | 600min |
| Compressive Strength | |
| 3days | 16 MPa |
| 7days | 22 MPa |
| 28days | 30 MPa |
| Water Absorption | 0.3 – 1 % |
Uses of Hydrophobic Cement
Waterproof cement is a highly versatile building material that is known for its exceptional ability to withstand wet conditions for extended periods of time. This makes it an excellent choice for use in environments where storage periods are long, and the climate is extremely wet. One of its most common applications is in tunnel construction, where repairs to underground structures can be difficult and costly.
Waterproof cement is also used extensively in the construction of dams, spillways, and other underwater structures. Due to its ability to resist water penetration, it is an ideal material for use in structures that are exposed to rain or rain puddling, such as green roofs, other kinds of roofs, parking structures, and plazas.
In addition to its use in above-ground structures, waterproof cement is also commonly used in drainage system works and manholes. It is an essential material for water treatment plants, dams, and retaining walls, where water resistance is critical.
One of the most significant advantages of waterproof cement is its ability to fix leaky pipes and basements without the need to stop the leaking. This makes it an invaluable material for addressing water damage issues, as it can prevent further damage to the structure while repairs are being made.
Overall, waterproof cement is a highly reliable and durable building material that can be used in a variety of applications. Its unique ability to withstand water penetration makes it a top choice for any construction project where moisture is a concern.
Advantages of Hydrophobic Cement
Hydrophobic cement offers several significant advantages over ordinary cement. One of the key benefits is that it provides long-lasting and durable repairs that can withstand the test of time. This makes it an ideal choice for construction projects where longevity and durability are important factors.
Another advantage of hydrophobic cement is that it has the same level of strength as ordinary cement. This means that it can be used for a wide range of applications, from building foundations to constructing walls and other structures.
One of the most notable features of hydrophobic cement is its fast setting and hardening time. In fact, it typically only takes around three minutes after being mixed with water for it to set and harden. This can be especially useful in situations where time is of the essence, such as when repairing a structure that needs to be used again as soon as possible.
Finally, hydrophobic cement also has the added benefit of being able to be painted within just one hour of application. This is because it sets and hardens quickly, allowing for a faster turnaround time in construction projects. Overall, the advantages of hydrophobic cement make it a popular choice for builders and contractors looking for a reliable and efficient building material.
Disadvantages of Hydrophobic Cement
Hydrophobic cement is known to have several drawbacks that need to be considered. Firstly, it cannot be used on frozen surfaces, which makes it impractical in colder climates. In addition, this type of cement cannot be used when the temperature drops below 40 degrees Fahrenheit, limiting its usage in certain weather conditions.
While hydrophobic cement can be useful for preventing leaks, it is not effective in addressing issues caused by condensation. It is essential to keep in mind that using this type of cement requires skilled labor and favorable climatic conditions, which may not always be available.
Lastly, the cost of hydrophobic cement is high, making it a costly option for many construction projects. Despite its benefits, it may not be the most practical or cost-effective choice in some situations. Overall, careful consideration is necessary before deciding to use hydrophobic cement in any construction project.
Health and Safety Precautions of Hydrophobic Cement
When dealing with dust, it is crucial to take precautions to protect yourself. Inhaling dust can be harmful, so it is important to avoid breathing it in. Additionally, if the dust comes into contact with your eyes or skin, it could cause irritation or other health issues.
One type of dust that can be particularly dangerous is silica dust. When inhaled, silica dust can cause lung problems. However, there is currently no conclusive evidence that silica is a carcinogen. To minimize the risk of inhaling silica dust, it is recommended to use protective clothing, such as gloves or masks.
In summary, it is essential to be cautious when dealing with dust. To avoid any potential health issues, it is crucial to avoid breathing in the dust and to protect your skin and eyes. When dealing with silica dust, taking extra precautions such as wearing gloves or masks can help minimize the risk of lung problems.