Water-resistant concrete, sometimes referred to as hydraulic concrete, is a specific kind of concrete made to resist exposure to water without losing its structural integrity. This substance is necessary for building water-resistant structures like foundations, bridges, and dams. Due to its special qualities, it is extremely useful in many different types of construction projects, particularly those that require longevity and durability.
The composition of hydraulic concrete determines its strength. Typically, it consists of cement, water, sand, gravel, and additional special additives to improve the material’s resistance to water. These additives make concrete perfect for use in damp or submerged environments by assisting it to set and harden even when exposed to water. The concrete’s performance, such as its compressive strength, durability, and resistance to environmental factors, is determined by the exact combination and caliber of these ingredients.
A precise recipe must be followed when making hydraulic concrete, and this recipe may change depending on the intended use and surrounding circumstances. To obtain the required qualities, the procedure calls for precise material measurement and mixing. Builders and engineers can choose the best kind of hydraulic concrete for their projects, guaranteeing durability and safety, by being aware of its technical properties and composition.
| Aspect | Details |
| Definition | Hydraulic concrete is a type of concrete that hardens through a chemical reaction with water, allowing it to set and gain strength even underwater or in wet conditions. |
| Main Components | Hydraulic concrete typically consists of cement, water, and aggregates like sand and gravel. Cement acts as the binding agent, while the aggregates provide bulk and strength. |
| Technical Characteristics | Hydraulic concrete is known for its durability and resistance to weathering and chemical attacks. It usually has a high compressive strength, making it suitable for structural applications. |
| Recipe | A basic recipe for hydraulic concrete includes 1 part cement, 2 parts sand, and 3 parts gravel or crushed stone, mixed with water in a ratio of approximately 0.5:1 (water to cement) to achieve the desired consistency. |
General information
GOST 4795-53 regulates the technical specifications, material properties, and requirements that hydraulic concrete must meet in accordance with standards.
Concrete is specifically designed for use in construction for a range of applications, including areas where the structure will constantly be submerged in water. Certain building types and environments call for different kinds of materials.
Types
- By location relative to the water level – the monolith can be underwater (constantly in the water) and above-water (located above the water level).
- By scale – concrete can be massive or non-massive.
- By placement features – external structures and those located in the internal zone.
- By the force of water pressure acting on the structure – pressure/non-pressure structures.
The grade of hydraulic concrete and the volume in which the required components are included in the composition determine many of the properties and technical regulatory characteristics.
The decision about which solution to use is made in light of the facility’s operational needs, the type of structure (massive, thin-walled, prefabricated, etc.), the local climate, etc.
- BNM – for the construction of massive above-water structures
- BGT – relevant for areas where the water horizon is variable
- BPT – mixtures for creating underwater thin-walled structures
Materials
Different types of cement, such as plasticized cement, hydrophobic, pozzolanic substance, ordinary Portland cement, and slag Portland cement resistant to sulfates, can be used as binder when mixing hydraulic concrete; the choice of cement depends on the operating conditions.
Here, the characteristics of each mixture must be taken into account. Puzzolanic cement has a higher monolith density, produces less heat, and exhibits a high degree of chemical resistance in freshwater or mineralized environments.
Low levels of water separation and poor frost resistance are two more characteristics of a mixture of this material.
The preparation of waterproof, frost-resistant solutions requires the use of plasticized and hydrophobic cement varieties. This is particularly crucial in regions with fluctuating groundwater exposure and harsh climates. It is feasible to cut heat transfer and cement consumption during the hardening process of such mixtures by 8–10%.
Cement that is resistant to sulfur is appropriate for building operations in extremely harsh environments with waters that are acidic in nature. For the construction of above-water structures, Portland cement with specific mineral additives in the composition and slag Portland cement are relevant.
GOST is followed when choosing fine and coarse filler. Microfillers, like fly ash, can be added to the composition to raise the density of the mixture.
- Plasticizers (introduced into the solution in a volume of up to 3%) – GKZh (silicon-organic additives), SNV (which stands for neutralized air-entraining resin), SYUB (sulfate-yeast mash), superplasticizer C3.
- Various types of structure compactors (introduced into the mixture in a volume of up to 1%) – sodium/potassium silicate, sometimes saltpeter (calcium nitrate), ferric chloride is often used.
- Hydrophobic substances (in a volume of up to 1%) – calcium/zinc stearate, sodium oleate and others.
Requirements and specifications
The standards state that any hydraulic concrete must have specific characteristics, regardless of the brand or compositional additives used.
The primary ones are: minimal shrinkage, maximum resistance to abrasion under the pressure of water and moisture, resistance to low temperatures, water resistance, water impermeability, minimal heat release during the hardening process, and the capacity to withstand significant deformations without collapsing.
- Compressive strength – measured by class, the hydraulic mixture must demonstrate up to B35
- Osenger tensile strength – up to bt3.2
- Water resistance level – up to W20
- Frost resistance – up to F600
Large volumes of hydraulic concrete are laid rapidly. They must thus, among other things, comply with the specifications pertaining to heat release during hardening.
To reduce the chance of thermal shrinkage and monolith cracks, the solution shouldn’t be heated too much during the hydration phase. When preparing the mixture, crushed ice and cooled filler can be added to the concrete for this purpose.
The main advantages and disadvantages of hydraulic concrete
The three main categories of hydraulic concrete are: regular mortar for blocks, foundations, various types of supports, pouring basements, and cellars; waterproof mortar for the construction of various types of hydraulic structures of above-water and underwater types (dams, dams, locks); and strong waterproof concrete, which is primarily used in the Far North for the construction of structures with special requirements. The classification of hydraulic concrete is based on the operating conditions and areas of application.
- High level of water resistance, regardless of specific operating conditions
- Good waterproofing properties, due to which the solution is not afraid of cutting and significant temperature changes
- Very high strength index
- Excellent frost resistance parameters, which is achieved due to the minimum volume of water in the mixture
Among the drawbacks are the high price, the requirement that the expert possess specific abilities and knowledge in order to work with the technology, and the impossibility of completing the task without the use of specialized tools and equipment.
Since concrete sets quickly, delivery can be problematic as the mixture is typically purchased from factories in the area. Furthermore, if this is not an issue in Moscow and the surrounding area, it may be challenging to locate hydraulic concrete in remote areas at a reasonable price.
When people inquire about hydraulic concrete, they typically start by focusing on its properties and composition, which are important for carrying out particular kinds of tasks.
Specialized concrete known for its capacity to solidify and harden in water is called hydraulic concrete. This property makes it perfect for foundations exposed to moisture and underwater structures. To improve its strength and water resistance, this long-lasting and adaptable material is made of Portland cement, water, aggregates, and particular additives. Comprehending the composition, technical attributes, and appropriate mix recipe of hydraulic concrete is imperative to guarantee its peak performance in construction endeavors, particularly in demanding settings.
A versatile and long-lasting material, hydraulic concrete is crucial for many types of construction projects, particularly those that involve water. For dams, bridges, and other damp structures, its capacity to solidify and harden even underwater makes it indispensable.
The strength and durability of hydraulic concrete are guaranteed by its special composition, which consists of cement, aggregates, water, and additional additives. To achieve the required technical characteristics, like high compressive strength and resistance to water infiltration, careful component selection and mixing are essential.
Hydraulic concrete is made with exact measurements and careful mixing, frequently by using special recipes made to fit the needs of the project. The success and longevity of the construction can be greatly impacted by knowing the characteristics and correct application of hydraulic concrete, whether it is for large-scale infrastructure or smaller applications.
Overall, many engineers and builders choose hydraulic concrete because of its strong performance in difficult situations. Experts who understand its composition and application can guarantee the construction of long-lasting structures.
