Large Diameter Column Forms from EzyTube

Charles Darwin Centre, Northern Territory

The Charles Darwin Centre is one of the newest high rise commercial buildings in Darwin, Australia. It comprised of 20 levels of premium grade office space which house many blue chip clients including approximately 50% of all the Northern Territory Governmental Departments. At ground level, there are numerous prestigious retail outlets with an impressive suspended concrete floor above which is 7 mtrs high in some locations.

There are approximately 12 round columns per floor level, with the lower 8 level utilising 1000mm dia concrete columns, and the upper 12 floors utilising 800mm dia concrete columns at approximately 3200mm high per level. Including the basement level, this totalled over 260 concrete columns at 800mm to 1000mm in diameter.

The closest suppliers of column forms to Darwin are located in Brisbane (3,400km / 2,112 miles away). To supply conventional round column forming tubes would occupy approximately 16 semi trailers at almost 1 trailer load per floor level.

Ezytube offered an effective solution by supplying these large diameter column forms in a palletised Flatpack format, which resulted in the entire project supplied in a series of easily handled small palletised loads in the equivalent of one semi trailer load.

In addition to transport savings, the labour and crane costs of handling the tubes was significantly reduced as the column forms for each suspended floor level were neatly packaged to an easily handled volume per floor level.

ezytube flat pack
40 x 1200mm dia x 3500mm

Introducing Ezytube Flat Pack

Ezytube Flat Pack is an innovative new formwork tube which is rapidly expanding in use to create round concrete columns on major construction projects.

Ezytube Flatpack is lightweight, easy to set up and remove, and occupies less than 5% of the volume that a round tube would occupy therefore transport costs to site are only a fraction of the cost compared to conventional round tubular column forms.

Ezytube flatpack is manufactured as a round tubular form, has a thin, high tensile strength wall and upon manufacture is flattened to an overall thickness of approximately 15mm. The tubes are then placed on a pallet and multiples of tubes are stacked on top until a height of the stacked tubes is achieved that the tubes remain to be stable on the pallet. The total number of tubes per pallet may be anything from 20 to 80 tubes per pallet depending on the diameter of the tubes, and the total weight that can be safely handled on the pallet.

Often, one level of tubes (10-40 tubes) may be packed onto one pallet, and separate pallets for successive levels stacked on top to minimise storage space on site and to ensure simplicity for the site storage are to the level on which the column forms are to be erected.

flatpack concrete column forms
Ezytube Flatpack 800mm and 1000mm dia 12 columns per floor x 5 floors

The flattened tubes are simply taken from the pallet, pushed roughly back into shape, placed over the steel reinforcing cage and held in place by regular formwork bracing to ensure that the form does not move during the pouring of the concrete.

forming concrete column with ezytube
Ezytube Flatpack used in a 'Pour Down' situation

Ezytube Flatpack is rigid enough to be placed in a suitably plumb position, and yet flexible to revert to the original round shape under the weight of poured concrete.

Class 2 (smooth) and Class 3 (spiral) concrete surfaces can be achieved with Ezytube Flatpack, and "Pour Up" or "Pour Down" set up methods can be equally accommodated.

Upon pouring the concrete, a slight vertical mark may be reflected at the crease in the tube, however in general this crease is minor and barely noticeable, and certainly within the surface tolerances specified for class 3 surface finishes.

Ezytube Flatpack is available in the nominal diameter range that the Ezytube Spiral tube range offers (150mm dia to 1200mm dia in 50mm increments - with the exception of 1050mm dia and 1150mmdia), and can potentially be supplied in lengths up to 8 mtrs (subject to diameters required- thicker wall tube used on higher large diameter tubes may result in a slightly more visible vertical crease).

concrete column finish
Ezytube Flatpack finish after stripping