For slipforming constant cross-sections – or cross-sections which do not change with height – the formwork with all the working platforms, is raised on climbing tubes by means of hydraulic jacks.
The active principle of the slipforming process consists of a quasi-continuous perpendicular lifting process of the formwork construction while all the usual steps executed concurrently: Forming, reinforcing, placing of concrete and aftertreating. The formwork grows upwards with the structure up to several metres a day. In general, the works are carried out in 24 hours shift rotations, but slipforming only during the day is possible, as well.
The stroke process is carried out in discrete steps of 20 to 25 millimetres in a determined time interval. Slipforming speed is usually between 3 to 5 metres in 24 hours. Nevertheless, with smaller dimensions of the prefabricated components, slipforming speeds of up to 10 metres in 24 hours can be achieved. Slipforming therefore stands for rapid construction progress, an economical use of resources and the highest possible health and safety standards.
Gleitbau have a world wide experience in the design and construction of storage silos by means of cylindrical slipforming technique, ranging from single wheat silos to huge plants for industrial products with 30 silo cells and more.
Silo construction is a traditional application of the slipforming technique – nevertheless Gleitbau’s engineers are engaged to develop modern, individual and economical improvements For example, combined construction methods that imply casting-in of embedments and special formwork for the execution of the inner cone.
Furthermore, heavy lifting technology can be offered for roof constructions and cones.