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Technical Dayta Sheet Compedium

CONTENTS CONCRETE REPAIR CORROSION CONTROL GROUTS & ANCHORS PROTECTIVE COATINGS INDUSTRIAL FLOORING SURFACE TREATMENTS JOINT SEALANTS CONCRETE JOINTING ROOFING WATERSTOPS WATERPROOFING JOINT FILLERS TIMBER FLOORING ALPHABETICAL Applications Instructions Preparation Saw cut or cut back the extremities of the repair locations to a depth of at least 25 mm to avoid feather-edging and to provide a square edge. Break out the complete repair area to a minimum depth of 25 mm up to the sawn edge. Clean the surface and remove any dust, unsound or contaminated material, plaster, oil, paint, grease, corrosion deposits or algae. Where breaking out is not required, roughen the surface and remove any laitance by light scabbling or grit-blasting. Oil and grease deposits should be removed by steam cleaning, detergent scrubbing or the use of a proprietary degreaser. The effectiveness of decontamination should then be assessed by a pull-off test. Expose fully any corroded steel in the repair area and remove all loose scale and corrosion deposits. Steel should be cleaned to a bright condition paying particular attention to the back of exposed steel bars. Grit-blasting is recommended for this process. Where corrosion has occurred due to the presence of chlorides, the steel should be high pressure washed with clean water immediately after grit-blasting to remove corrosion products from pits and imperfections within its surface. The prepared area should be blown clean with oil-free compressed air. Reinforcing steel priming Apply one full coat of Nitoprime Zincrich to all exposed reinforcing steel and allow to dry before continuing. If any doubt exists about having achieved an unbroken coating, a second application should be made and, again, allowed to dry before continuing. Substrate priming Several hours prior to application the prepared concrete substrates should be saturated by filling the prepared area with clean water. Immediately prior to application of Renderoc Rapid any excess water should be removed to leave the concrete substrate in an SSD (saturated surface dry) condition. Mixing Care should be taken to ensure that Renderoc Rapid is thoroughly mixed. A forced-action mixer is essential. Mixing in a suitably sized drum using an appropriate spiral paddle such the Protool HS2 140 x 600 M14 Helical mixing paddle (product code: TT-614217) or equivalent at a slow speed (400/500 rpm) using a heavy-duty mixer, 1500W such as Protool MXP 1602 E (product code: TT-621941) or equivalent is acceptable for the occasional one-bag mix. Free fall mixers must not be used. Mixing of part bags should never be attempted. It is recommended that only one bag of Renderoc Rapid is mixed at any one time to ensure that all the mortar can be placed within its working life. Place 2.5 L of drinking quality water into the mixer and, with the machine in operation, add one full 20 kg bag of Renderoc Rapid and mix for 3 minutes until fully homogeneous. Do not mix for longer than this time to ensure that the available working life is not reduced. Note that powder must always be added to water. Consistency Water Addition (Litres) Yield (Litres) INDEX 24 Page 2 Pourable 2.5 10.23 Application Apply the mixed Renderoc Rapid on to the SSD substrate as soon as possible after mixing. The mortar should be applied evenly by trowel and tamped in place with a wood float to ensure full compaction. Thoroughly compact the mortar around any exposed steel reinforcement. Renderoc Rapid can be applied up to 250 mm thickness in single applications. Note: the minimum applied thickness of Renderoc Rapid is 25 mm. Build Up Repair secions greater than 250 mm thickness can be achieved by application of multiple layers. In this instance, the surface of the intermediate layers should be scratchkeyed and allowed to set for a minimum of 2 hours before continuing. Repriming and a further application of Renderoc Rapid may proceed at this time. Note: Repairs greater than 0.15 m³ (150 litres) may exhibit significant exotherm. Contact Parchem for specific application advice in these situations. Finishing Renderoc Rapid should be struck off to the correct level and finished with a steel trowel to fully close the surface. If a textured surface is required, this can be achieved using a suitable roller or brush. The completed surface should not be overworked. Low temperature working In cold conditions down to 5°C, the use of warm water (up to 30°C) is advisable to accelerate strength development. Normal precautions for winter working with cementitious materials should then be adopted. The material should not be applied when the substrate and/or air temperature is 5°C and falling. At 5°C static temperature or at 5°C and rising, the application may proceed. High temperature working At ambient temperatures above 35°C, the material should not be used as premature setting may occur. Curing Renderoc Rapid is a cement-based repair mortar. In common with all cementitious materials, Renderoc Rapid must be Fosroc® Renderoc Rapid


Technical Dayta Sheet Compedium
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