Technical guide with sources · ROLL Lab
Cardboard column formers: how they work
In shortCardboard column formers are large-diameter tubes with a waterproofed inner surface: they are filled with concrete, stripped once it has set and give round columns with no joints.
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How they work
The former is stood upright, braced and filled with concrete. The inner lining stops the board absorbing water from the mix and gives the column its surface finish. Once the concrete has set, the tube is scored and stripped off: it is single use and goes back into paper recycling.
What to check
- Column diameter and height, and the pressure of fresh concrete, which grows with the height of the pour.
- Type of inner lining and the finish you want (smooth, fair-faced).
- Storage on site, protected from rain and damp.
- Bracing and plumb during the pour.
Frequently asked questions
How do cardboard column formers work?
They are large-diameter tubes (from about 150 to over 1,000 mm) with a treated inner surface. They are filled with concrete and stripped once it has set. They are single use and give round columns with no joints.
Sources
- ISO 11093 (parts 6, 7, 8, 9)
- ISO 13542
- CCTI T-158, T-159
- ROLL Lab calculation
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