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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 418 Technical Data Eccovoid Sheet Collapsible void former Uses To separate concrete slabs, ground beams and pile caps etc from unstable expansive soils that can exert significant swelling pressures on structural foundations. Eccovoid provide a temporary support for the concrete during curing but collapse over time as the cardboard product biodegrades naturally. Advantages „ Environmentally friendly „ High load capacity when dry „ Light weight and easy to install „ Fully glued units are easy to cut into odd shapes „ Can be stacked to achieve greater void depths „ No assembly required Description Eccovoid is a honeycomb bonded partition panel selected for its uniformity of manufacture and exhibiting excellent dry strength properties. It will support the weight of construction traffic, reinforcement and wet concrete until the cured concrete gains sufficient strength to be self-supporting. Be aware that the ground and atmospheric ambient moisture conditions are critical to the successful utilisation of this product and hence it must be used only in dry conditions. Eccovoids are used to separate slabs and ground beams from unstable expansive soils. Eccovoids will break down by the absorption of moisture and / or from soil bacterial attack to create a void beneath the slab or beam. Eccovoid is made from 400 micron cardboard with a honeycomb cellular core between face sheets. Because they are of glued construction they can be easily cut on site to fit most situations. Design Criteria Geological data indicates that unstable expansive soils occur in all states of Australia but in particularly in the eastern states. Building foundations and ground slabs interrupt the natural evaporation of soil moisture and cause a build up of its moisture in the ground beneath the structure which leads to the swelling of the sub-foundation clays. Tests by the Queensland University of Technology (QUT) show that the time required for swelling pressures to cause damage is generally a min of 14 days or longer. Upward movements of the soil vary with the depth and type of clay deposits. Exploration of the soil profiles for any structure should be undertaken by experienced and properly qualified soil testing engineers. Approximated void former depths for known heave values: Potential Heave Void Former Depth 60 mm 100 mm 100 mm 150 mm 150 mm 200 mm Working loadings The following working loading is suggested using fully dry materials; any moisture contaminating the material will reduce this working load. Standard Eccovoid 3.0 tonne/m² For working loads above 3.0 tonne/m², contact Parchem for further advice. Installation Instructions Transport and Site Storage Eccovoid void formers are made from 400 micron cardboard and throughout their use this must be taken into consideration. Moisture either induced or natural, is the key to degradation and hence they MUST only be used in dry conditions with the utmost care being taken to keep moisture away from the product until the concrete has achieved its self supporting strength otherwise premature collapse will occur. Delivery of void formers to site MUST be organised so that they can be used immediately to minimise exposure to the elements. Transport, store and handle the product in such a manner as to keep it off the ground and undercover in order to keep it dry and allow the air to circulate and prevent condensation at all times. Bar chair positioning The concentrated loading from bar chairs must be spread to avoid puncturing the face sheet. Flat based chairs can generally be used straight on the surface. Wire leg type bar chairs will require bar chair plates under them to prevent puncturing the surface sheets. Generally more bar chairs are required to reduce the puncture loadings on the Eccovoid void formers. Installation Use minimum 0.2 mm thick polythene sheeting on the topside of the boxes to help protect the void former from the elements and the wet concrete. This also helps protect the underside of the slab from moisture. The boxes shall be placed together so that the concrete cannot fall down between the boxes. The polythene sheet is to be lapped 150 mm at joins and taped. Take the polythene sheeting down September 2007


32857 Parchem Technical Data Compendium 2015_Crop4emag.pdf
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