Polyurethane injection is a special method used for waterproofing and repairing cracks in the building and construction industry. The material used in this method easily penetrates even the narrowest cracks and swells in a short time to close the cracks. The process is used for purposes such as waterproofing, crack repair and ground stabilization.
Its long-lasting and durable structure ensures permanent results. It is a highly effective method for filling gaps that will cause water leakage such as cracks and cold joint openings.
What is Polyurethane Injection?
Polyurethane injection is an insulation method made by injecting polyurethane resin into cracks and gaps in order to provide waterproofing of structures.
In addition to its flexible and durable structure, it is the injection of a chemical resin, which rapidly increases in volume when in contact with water, into areas such as cracks and cold joint gaps. The injected substance is a polyurethane-based resin and can be defined as waterproofing foams. This method is used in many places, from small-scale structures such as houses and buildings to large-scale projects such as subway tunnels, industrial areas and huge reinforced concrete structures.
Polyurethane injection is used to close cracks and water leaks at points where the source cannot be clearly detected from the outside and even if it is detected, there is no chance of intervention. Water leaks coming from cracks in the concrete or cold joints between the wall and concrete are prevented in this way. Without the need to break the walls, micro cracks and capillary structures in them are completely closed.
This material is a polyurethane based resin. Its most important feature is that its volume increases 20-25 times when it comes into contact with water. When it reacts with water, it swells quickly and fills all gaps effectively.
Polyurethane Injection Features
The technical features of this application have been instrumental in its popularity and widespread use. Its prominent technical features can be listed as follows:
- These resins have the flexibility to easily adapt to structural movements. Thanks to its flexibility, it is not affected by ground tremors, vibrations and other dynamic loads that the structure will be exposed to over time. In addition, it continues to fulfill its function after the movements that will occur due to the settlement of the structures.
- It has high adhesion strength. It easily adheres and adheres to surfaces such as concrete and stone. This is one of the main reasons for the long life of the application.
- This substance swells rapidly when it interacts with water, and after the curing process is completed, it has a watertight structure. It absolutely does not leak water.
- Curing time is extremely short. This time, expressed in seconds, allows the results of the application to be seen in a very short time.
- The volume increase is perhaps its most important feature. When it comes into contact with water after application, the reaction starts and its volume increases rapidly. The volume increase occurs at 20-25 times levels.
Recently waterproofing materials Polyurethane injection, which is one of the most preferred products among the most preferred products, is preferred as a crack concealer.
How is Polyurethane Injection Applied?
Polyurethane injection is applied using special equipment. The application includes certain stages in itself. The steps to be followed for the application are as follows:
- First, the points where water leakage or cracks in the concrete are present are carefully examined. The locations of cracks and leaks are determined.
- Holes are drilled at 30-40 cm intervals in the area where there are cracks. The holes drilled have an inclination of 45 degrees. Thus, much larger areas in the concrete can benefit from the application.
- After the holes are drilled, high-pressure air is pumped into them. Thus, dirt, dust and concrete pieces remaining inside are removed. A clean surface is created for the application.
- Steel dowels are inserted into the holes and nozzles are placed on top of them. These are also called injection ports.
- After the necessary preparations are completed, the pipe of a special equipment is inserted into the nozzles and polyurethane-based resin is injected into the concrete. This process is called polyurethane injection.
- The injection process continues until the applied resin is seen to exit from other holes or from a different point. Polyurethane-based resin is injected through all the holes drilled.
- When this substance comes into contact with water, a reaction starts and its volume increases rapidly. At this time, it has high adhesion. When the reaction is over, the curing is completed and the stickiness of the formed foam ends after about 120 seconds.
This application ensures effective sealing of cracks inside the wall. Apart from waterproofing, it is also used for structural reinforcement, ground stabilization and different industrial applications.
In polyurethane injection, contact with water is required for the reaction to start. However, when there is no contact with water, although there is no expansion and volume increase, hardening occurs by forming an elastic mass. In other words, it gives effective results in closing cracks in places where there is little water.
What Does Polyurethane Injection Do?
Polyurethane injection is one of the methods developed for waterproofing. It is used to fill capillary cracks in concrete that cannot be seen from the outside and cannot be intervened. However, this is not its only function.
This method, which gives effective results in eliminating water leaks, also provides repair of cracks. The substance that fills the cracks in the concrete and adheres to the surfaces here contributes to strengthening the structures and increasing their service life.
Sealing cracks for concrete protects the iron and metal reinforcement (if any) in the relevant area from corrosion. Moisture and chemicals coming through cracks cause corrosion of metal reinforcements and cause the metals to decay over time. However, completely sealing the cracks with this application eliminates the risk of corrosion and ensures that the structures remain intact.
When buildings are constructed, not all reinforced concrete sections are built at the same time. There are often gaps, often invisible to the eye, between adjacent but not simultaneously constructed concretes. These areas, called cold joints, are one of the points where water leaks occur intensely. With polyurethane injection, these areas are filled and risky situations are eliminated.
Polyurethane-based resin is durable but not as strong as concrete and metal. Although this may seem like a disadvantage, it disappears when they fill all the voids in concrete. Thus, they contribute to strengthening and reinforcing structures.
Waterproofing and Crack Repair with DryFix DF PUR INJECTION 2K
DryFix DF PUR INJEKTION 2K, which has the ability to adhere to wet and dry surfaces, stands out with its low water requirement for curing and chemical reaction. The solvent-free, two-component polyurethane-based injection resin is non-toxic and non-biodegradable by microorganisms. This product, which remains active even when water is low, provides effective results in waterproofing and crack repair.
It is used for the insulation of thin cracks and joints in expansion joints, foundations, underground curtain walls, sewers and similar types of structures. Application is made with the accelerator known as CATALIZOR 10. Accelerator is applied by adding between 2-10%. After its reaction with water, a non-shrinking and dimensionally stable foam is formed. This foam provides waterproofing and filling of cracks.
If you want to prevent water leaks from inside concrete structures and fill invisible cracks, you can choose this product for polyurethane injection.
