DYNAVOID™ was developed by Beaver Plastics to meet the requirements for a moisture tolerant void material to be used under structural concrete. It is a Dynamic Inclusion, mechanically responsive to expanding soils. Beaver has earned both U.S. and Canadian patents for the product.
DYNAVOID is designed to bear the weight of a very heavy structural slab until it has developed enough strength to become self-supporting. Long-term sustained stress from an expanding sub-grade then causes DYNAVOID to collapse due to thermoplastic creep. As the soils expand, the geometry of DYNAVOID converts this vertical strain into a horizontal deflection of supporting legs. Deflection continues until ‘over-center’ mechanical failure, with the collapsed leg segments nested together. A limited amount of simple compression will then continue to absorb sub-grade expansion as with ordinary foam materials.
DYNAVOID is produced in different performance ranges and in thickness’ of 100 and 150 mm (4” or 6”), in 1220 by 1220-mm (4’ x 4’) panels. The correct version must be selected to ensure the slab will be supported as well as creep and collapse should sub-grade expansion occur.
Download the Dynavoid brochure for the product selection chart.

| Dynavoid brochure - 730KB | |
| Dynavoid Specifications - 101KB | |
| Dynavoid Specifications - 67KB | |
| Dynavoid Product Descrition - 89KB |
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