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32857 Parchem Technical Data Compendium 2015_Crop4emag.pdf

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 INDEX 512 ® Vandex® BB75-Z Properties Form: Cementitious powder Colour: Cement grey Bulk density: 1.30 - 1.50 kg/L Compressive strength: 40 MPa after 28 days water storage Bending tensile strength: 7 MPa after 28 days water storage Elastic modulus: 2.16 x 104 MPa after 28 days air cure at 23°C, 50% RH Initial setting time: 2 - 4 hours Full cure time at 5 days 20°C 50% RH: Physical or chemical change: Chemical cure Application temperature: 5°C - 30°C Service temperature (continuous ambient): Minus 40°C - 120°C Chemical resistance Vandex BB75-Z protects concrete against sewerage water, sea water, aggressive ground water and a range of chemical solutions. Vandex BB75-Z is approved for use in contact with potable water and is therefore suitable for the treatment of water storage tanks, reservoirs, water towers etc. Maintenance No special requirements, any damage identified during normal inspections should be water blasted clean, repaired and recoated as appropriate. Specification clauses Where so designated on the drawings, surfaces to be waterproofed shall have a surface applied, cementitious waterproofing membrane installed. The waterproofing must form an impermeable layer on the surface of the substrate and must not rely on crystal growth within the substrate in order to be effective. It must have a proven capability of sustaining pressures of 7.0 bar (70 metre water head) while maintaining its waterproofing integrity. The waterproofing treatment must have a compressive strength greater than 35 MPa and bending tensile strength greater than 5 MPa after 28 days water cure. The cementitious waterproofing membrane must have a modulus of elasticity greater than 1.8 x 104 MPa after 28 days cure. The setting time for the waterproofing must be in the range 2 - 4 hours and the bulk density for the dry powder before mixing must be in the range 1.30 - 1.50 kg/litre. The cementitious waterproofing membrane must be non- toxic and be capable of being applied to concrete and masonry surfaces by trowel, or as a slurry by brush or by spray application through a hopper gun. The waterproofing must be installed by a prequalified contractor nominated by the supplier and both the manufacturer and supplier must be accredited to ISO9001. Vandex BB75-Z supplied by Parchem is such a product. Surface preparation When applying Vandex BB75-Z to existing concrete or masonry, all surfaces to be waterproofed should be clean, sound and free of concrete curing compounds, form release agents, paints and all other coatings, dirt and contamination. Concrete surfaces should be prepared by water blasting, grit blasting or grinding in order to remove the laitance and open the pore structure of the concrete in preparation to receive the Vandex BB75-Z. Concrete surfaces should be free from major imperfections. All major imperfections must repaired with a suitable cementitious reprofiling mortar such as Vandex Uni Mortar 1-Z which is suitable for reprofiling depths of 6 mm to 12 mm. Larger repairs may be carried out using multiple layers of Uni Mortar 1-Z or a suitable high build cementitious repair mortar. Priming Priming is not normally required on good quality concrete substrates, however all surfaces must be pre-watered before applying Vandex BB75-Z. Movement joints All expansion and movement joints should be sealed with a suitable joint sealant after application of the Vandex BB75-Z. Consult your local Parchem sales office for advice on the joint sealing method best suited to your application. Cracks All shrinkage and non-moving structural cracks having a width equal to or less than 0.3 mm will be waterproofed by applying Vandex BB75-Z directly bridging over the crack. Static cracks wider than 0.3 mm must be routed out to form a ‘V’ shaped groove with a hand or pneumatic chisel to a depth and width of approximately 25 mm. These larger cracks must be repaired by priming the chiselled out crack with two coats of Vandex Concrete Grey, followed by the application of Vandex Uni Mortar 1-Z to fill the rebate flush with the concrete surface. All of the above products must be installed ‘green on green’, before the previous layer has dried out. Live cracks cannot be waterproofed with Vandex BB75-Z. If the structure contains live cracks, Vandex BB75E-Z, an elasticised cementitious waterproofing membrane should be considered. Consult the local Parchem sales office for advice regarding the best method of waterproofing live cracks.


32857 Parchem Technical Data Compendium 2015_Crop4emag.pdf
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