Set retarder in aqueous solution to be applied, using a low pressure airless pump, on fresh concrete surfaces, to allow removal by washing with water, a cortical layer a few millimetres thick, and then expose the aggregate forming the concrete. Specific for the realisation of floors with landscape/environmental value with the "washed gravel" technique.
Density: 1.03 kg/dm³
Shelf-life: 6 months
Temperature of use: +5 / +35 °C
- Light blu
- Plastic can 10 kg
- Plastic can 25 kg
- Plastic can 5 kg
Surface gripping deactivator, in aqueous solution, to be diluted; based on polysaccharides, specific catalysers and antifoaming agents, allows for inhibiting the cement hydration reaction and slowing down the speed in gripping, only for a surface layer a few millimetres thick, without altering in any way the performance characteristics of the concrete flooring.
From 0.10 to 0.15 kg of PRERIT SOLUTION for every square metre of surface to be deactivated.
Construction of concrete floors with a high aesthetic value with the technique of the "washed gravel" (extrados with "exposed" aggregates).
Apply on site and float, with the usual methods, a packaged concrete on the basis of design and regulatory requirements.
PRERIT must be used in pure form (without dilution). With the concrete still in "fresh" condition, apply by spraying the set retarder, in the amount determined in the preliminary tests, depending on the "washing" depth desired. Usually, for an inhibition depth up to 2-3 mm, the dose of the product is equal to about 100-150 g/m².
Indicatively, after a time between 2 and 24 hours, remove the delayed superficial cement paste, with pressure wash from 120 to 200 bar, displaying the surface gravel. The washing times and pressures depend on the climatic conditions in which the work is being carried out, the mix design of the concrete and other variables. Do preliminary tests to better calibrate these important parameters.
- Low pressure airless nebulizer
- Floor screed
The aesthetic effect is considerably influenced by the depth of removal of the cortical layer of concrete. To obtain results to your satisfaction, it is advisable to carry out preliminary tests with the materials and the working conditions that will characterise the processing. Indeed, the delay times and the thickness of the washing depend on several factors, such as the type of cement, the amount of cement, the distance between the concrete mixing plant and the unloading site , the water/cement ratio, the temperature of the fresh concrete, the ambient temperature, the ventilation etc..
Carry out the washing stage within 24 h of the day of laying the flooring; waiting too long could compromise the effectiveness of the inhibition and therefore not allow the success of the "washed gravel" effect.