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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 Fosroc® Conbextra UW Instructions for Use Preparation The substrate surface must be free from oil, grease or any loosely adherent material. If the concrete surface is defective or has laitance, it must be cut to a sound base. Substrates which are permanently immersed should be sand-blasted or cleaned with a high pressure water jet. Non-immersed or intermittently immersed substrates can be prepared using these techniques. Alternatively scabbling or bush hammering may be appropriate. Formwork The formwork should be constructed to be leakproof as Conbextra UW is a free flowing grout. This can be achieved by using foam rubber strip or construction silicone sealant beneath the constructed formwork and between joints. Mixing and Placing Mixing For best results a mechanically powered grout mixer should be used. When quantities up to 40 kg are used, a slow speed drill fitted with a high shear mixer with a minimum 1200W and between 300-650 rpm. The Protool MXP 1602 E mixer (product code: TT-621941) or equivalent is recommend with the Protool HS2 140 x 600 M14 Helical mixing paddle (product code: TT-614217) or equivalent. Larger quantities will require a high shear vane mixer. Do not use a colloidal impeller mixer. It is essential that machine mixing capacity and labour availability is adequate to enable the grouting operation to be carried out continuously. This may require the use of a holding tank with provision for gentle agitation to maintain fluidity. Measure accurately 4.4 litres of water for each 20 kg bag into the mixer. Slowly add the Conbextra UW whilst mixing continuously. When all the powder is added mix continuously for 5 minutes ensuring a smooth even grey coloured consistency is obtained. (Fluidity will increase with increased mixing). Placing Place the grout within 20 minutes of mixing to gain the full benefit of the expansion process. Continuous grout flow is essential to prevent any air or water entrapment. The mixed grout should be poured or pumped through a flexible tube, having a minimum diameter of 50 mm, to the lowest point in the form. Filling/bulking out of the grout should not exceed a ratio of 1:1. Please refer to the Conbextra Grout Aggregate TDS for more guidance on bulking out of cement based grouts. Care must be taken at the start of the grouting operation to restrict the grout flow so that water is not entrapped. The tube may be raised as necessary to reduce any back pressure. It should not be raised above the surface level of the grout. Conbextra UW can be placed in thicknesses from 10 mm up to 80 mm in one pour when used above water. When used underwater, the heat sink effect in this environment will allow thicknesses of up to 150 mm to be placed. For thicker sections, up to 200 mm above water and 400 mm underwater, it is necessary to fill out Conbextra UW using Conbextra Grout Aggregate. The ratio of aggregate added to Conbextra UW should not exceed 1:1 by weight. For such mixes a concrete mixer should be used. Unrestrained surface area should be kept to a minimum. Curing Curing will not be required in intermittently or totally submerged situations. However, when cast above water, exposed areas should be thoroughly cured. This should be done by the use of Concure curing membrane, continuous application of water and/or wet hessian. Cleaning Because of its water resisting properties, equipment used for Conbextra UW will be harder to wash than with other cementitious grouts. The use of hot water for cleaning purposes will assist. Cured material can only be removed mechanically. Limitations Conbextra UW must not be applied below 5°C. Estimating Supply 201030 - Conbextra UW is supplied in 20 kg moisture resistant bags. Yield Allowance should be made for wastage when estimating quantities required. The approximate yield of a 20 kg bag when mixed with 4.4 litres of water is 11.60 litres. Storage Conbextra UW has a shelf life of 12 months if kept in a dry store in sealed bags. If stored in high temperature and high humidity locations, the shelf life may be reduced. INDEX 110 Page 3


Technical Dayta Sheet Compedium
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