Column
Formwork

Column formwork is a steel formwork system that maintains the design cross-section and verticality of a reinforced-concrete column throughout the pour. For circular columns, the formwork consists of half-shells bolted together. Stiffeners on the outside of the shell carry the fresh concrete pressure, while the connecting flanges ensure that the two halves close on the same axis. Square, rectangular and special geometries follow the same logic, using made-to-measure panels and corner details.

The formwork is manufactured in the workshop, erected on site and struck once the concrete has reached the required strength. Because the same formwork can be re-erected at the next level or on the next column, the erect-and-strike sequence is planned from the outset on tall and repetitive column work. The aim is not just to shape the concrete, but to keep the surface finish, diameter and verticality consistent from one pour to the next.

Half-Shells for Circular Column Formwork

In circular column formwork, two half-shells join to form a complete circle. The diameter, pour height and concrete pressure determine the shell plate, the stiffener spacing and the bolt pattern. If the flanges do not close fully, the column loses its roundness and the joint leaves a mark on the surface. For this reason, the joints, clamps and supporting members are detailed before fabrication, and the tightening sequence on site follows these drawings.

On tall columns, the formwork may not cover the full height in a single piece. With staged pours, the lower shell is struck, raised to the next level and the work continues with the same system. This cycle is arranged so that it does not clash with climbing formwork or a conventional scaffolding arrangement. Reinforcement, embedded plates and starter bars must be in place before the pour; opening the shell to add a missing anchor after the formwork has been closed costs both time and geometric accuracy.

Rayf Teknik treats column formwork not as a fixed catalogue size, but as a fabrication developed around the diameter and height of each project. The Taksim column formwork images show this production in the workshop and ready for dispatch: painted steel shells, stiffeners and flanged joints. The same formwork can be reused on the next job if the diameter matches; if the diameter changes, the shell is renewed, while the supporting structure and suitable connection components can be retained.

During erection, the axis and verticality are set before the first pour. As the concrete is placed, vibration must not shift the shell, and the concrete consistency must not generate more pressure than the stiffener design allows for. The formwork is never struck before the concrete has gained enough strength to hold its own shape. Striking too early distorts the circle; striking too late lets the formwork bond to the concrete and damages the surface.

Whether the formwork is purchased or deployed on a site contract, site supervision can be provided for the initial erection and the first pour. At handover, the diameter, joint details and operating notes are documented. In this way, column formwork is not a one-off sheet-metal job but a production tool that is re-erected time after time, with a dimensional record kept throughout.