- The water jet penetrates existing cavities and cracks.
- By exposing the concrete with the water jet for a certain time, you reach the desire depth.
- By changing the angle, the remaining material under the rebar (the shadows) will be removed.
- A perfect removed area of deteriated concrete which now is ready for a new layer of concrete.
The high-pressure water jet creates overpressure in the structure when it enters the concrete by using the permeability in the concrete. When the pressure exceeds the tensile strength of the concrete, then the concrete will be removed without causing any damage to the remaining structure.
Hydrodemolition – Selective removal – Robotic process
The water jet travels over the surface by means of a robot carrier at a constant speed and a pressure range of 1000-1600bar. The “low-pressure” hydrodemolition method has a selective effect on the concrete. This means that the poor and deteriorated concrete will be removed, and sound concrete will remain. The sides and the bottom of the cut will be rough because it follows the strength quality of the concrete.
Hydromilling – None-Selective removal or Controlled depth removal – Robotic process
The water jet travels over the surface by means of a robot carrier at a constant speed and a pressure range of 2000-3000bar. Higher pressure has more of a cutting effect on the concrete and the result will be more even both on the sides and in the bottom of the cut. It will remove what is set in the control system, regardless of the concrete quality consequently is it a non-selective removal.
Water jetting – Non-Selective removal – Manual operation
The water jet is a manual operation, the most common is 2000-3000bar. The operator is using a hand lance, mainly used on areas that are not accessible for the robot to reach. The maximum reaction force is 250N so this method is slow compared to the robotic process.
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