Doing rehabilitation of concrete structures, you must combine several principles and methods to achieve the desired result.
If you have a concrete structure with a lot of damage and a large amount of reinforcement corrosion, we use methods to stop further corrosion. This is done, for example, by applying coatings, impregnation or molding with a mortar or concrete. Corrosion protection must also be ensured by joining between reinforcement and new mortar / concrete.
For concrete rehabilitation we use concrete spraying (dry spraying) in some cases. This provides good filling and compression around reinforcement iron and this method is suitable for heavier rehabilitation, for example: Underside of dock or bridge. Multibetong has great expertise in the use of dry spraying.
Workmanship and proper selection of products for surface treatment of concrete and walls provide results that last.
Casting of new concrete foundations for pipelines / anchoring blocks. This job consisted of a pipeline of 320 meters and diameter Ø 2000.
Rehabilitation of dam Foundation and new casting. Helicopter was used regarding this. Total length of dam 210 meters.
Grouting, pouring with thin-flowing, possibly expanding, mortar (grouting mortar) of joints, cracks, holes or and the like. In constructions of concrete or masonry, for example: by repairs, bolt fixing and the like or in the filling of joints between prefabricated items.
The method is often used for repairs and fixing of bolts or supporting steel structures.
Putzmeister Grouting pump. Typical pump for grouting and support molding.
Sealing and stabilization in mountains and concrete structures. The method is used to rebuild damaged concrete and is effective when there are cracks and leakage. The injection mixture is forced into open pores and bursts under pressure and expands in contact with moisture so that the scratch is sealed. The purpose of the work and moisture conditions will determine the choice of method and materials
Injection of water leaks in rock and concrete can be divided into 2 main groups:
► Cement injection is used to seal leaks by dam systems and tunnels. With the help of cement injection you can get cracks and cavities in rock and concrete filled. Cement injection is also suitable for stabilizing soils.
► Chemical injection is used for sealing smaller scratches and cracks in rock and concrete structures.
Using wire saw, you have many options and can cut out whatever it may be. Wire saw can be used for example in mountains where blasting is not possible. Removing old concrete foundations is done easily and safely with this method.
Wire sawing gives less shakes, dust and noise. Finer cutting edges and less damage to the terrain.
Place the wire around the surface to be sawn. When the wire runs at high speed while tightening, the material is cut rapid. Both horizontal and vertical cutting into mountain sides are possible.
Structures are cut from a safe distance, which means that the work is carried out in a safe and harmless way. With a diamond wire saw it can be sawn in heavily reinforced concrete.
Multibetong AS uses Pentruder wire saws – for all purposes – granite, concrete, steel
The pictures show the old foundation that is removed with wire saw. A total of 48 foundation and 3 anchoring blocks. The concrete was carefully sawed away and replaced with new ones.
Using extremely high-water pressure removes damaged concrete and rust from reinforcement iron bars without damaging the surrounding area, leaving a clean and strong surface.
The method is a quick and effective method of removing concrete which also limits the removal of intact concrete to a minimum.
Water demolition does not develop any micro cracks.
The advantages of water demolition are:
► Removes lightweight concrete at different depths ► Separates easily between bad and good concrete ► Large capacity ► Ensures good adhesion ► Do not create micro cracks ► Do not damage the reinforcement ► Does not cause vibrations or shaking in the structure ► Provides less load for the operator than with chiseling machine ► Well suited for areas with dense reinforcements
Water gun with handgun for casting of cast iron.
The picture shows water mapping of anchoring pads (power supply), for replacement of poor reinforcement. In this case, robot was used.
Water demolition with a handgun
Multibetong AS has equipment for performing various types of water demolition jobs.
We also have expertise in chiselling underwater using camera and video.
Sandblasting is a common method to use when cleaning larger areas. But also smaller structures like tanks, containers and pipes.
Compressed air from an air tank and sand in a proper mixing ratio is blown through a hose. When the sand hits the surface, the material is grinded / torn off. The surface is left clean and ready for after treatment. The size of the sand grains varies from 0.05 mm to 3 mm.
This method can be used to remove rust, old paint, cleaning of hard surfaces and more. On surfaces where it requires more gentle treatment, soft abrasives are used instead of sand.
The benefits of sandblasting are:
► Effective for removing thin and crisp paint layers ► Can achieve varying roughness if desired ► Highly effective for removing corrosion on steel ► Effective in hard reachable places due to small dimensions of the hose and nozzle ► Opens pores and scratches in concrete ► Leaves a rough / structured surface to secure optimum adhesion ► Affordable equipment ► Fast rigging time
Insulation foam is a simple and affordable alternative to traditional insulation materials. The polyurethane foam provides both thermal and acoustic insulation, waterproofing and radon barrier in one and the same product. Continuous application with a special syringe helps to avoid thermal bridges and leaks at joints and cracks.
Polyurethane insulation foam is a kind of insulation that we will be seeing more of in the future. The possibilities and areas of use are many.
Insulation of containers with polyurethane foam
Insulation of water pipes
The image shows the sprayer is used for insulation with polyurethane foam
There are several different types of foam, depending on what to isolate
►Open LOC foam: Used for internal insulation and noise reduction. ►Closed LOC foam: Used for ground insulation with radon barrier, exterior roof, tanks, pipes, etc.
Core drilling is dust free and cuts through steel reinforcement bars without any problems. It is a precise and powerful drilling technique that makes holes in concrete, Leca and all other types of stones. There is no vibration at core drilling, and therefore no structural damage because the reinforcement does not loosen.
Core drilling is widely used in sampling of hardened concrete.
Multibetong AS has four sizes of core drilling equipment. We often use core drilling in connection with wire sawing.
Core drilling is an economical, fast and clean process.
The picture shows core drilling in concrete wall. For this job a 900mm drilling bit was used.
Demolition / Environmental sanitation
Multibetong AS is certified in demolition and environmental sanitation. We have had several assignments for major clients.
► Building ► Fuel depots ► Shooting range ► Large commercial building ► Production equipment ► Docks (concrete and wood)
Polyurea is a relatively new type of coating. In the same way as epoxy and polyurethane, polyurea chemically hardens when the components are mixed together.
This is a highly elastic, waterproof, and strong material that meets the strictest wear and tear requirements, as well as requirements for bridging over fissures. It hardens in seconds and can be loaded directly after application.
The product is applied with a two-component high pressure reaction syringe, with high pressure and temperature, where the mixture takes place at the extremity of the nozzle.
Corrosion protection, wearing layer and membrane on steel and concrete structures including materials such as metal, fiberglass, wood, styrofoam and a various plastic materials that are exposed to impact and abrasion. The coating can be used almost everywhere, as it can be applied in temperatures from below freezing point to more than 100 degrees Celsius.
Before and after pictures where polyurea coating was used in drinking water pool. This is to prevent bacterial growth and easier cleaning of the pool.
The coating is also very chemical resistant, which makes it very suitable for, for example, industrial floors with a lot of wear and effects from chemicals and mechanical equipment. And at the cleaning plants. Polyurea coatings are also excellent for placing in large wardrobes, and showers.
Polyurea coatings can also be placed in a drinking water pool. This type of coating is approved by the public health institute for drinking water.
The image shows the sprayer used under polyurea coating.