Henrik L. Funke

Flexible fiber-reinforced plastic formworks for the production of curved textile-reinforced concrete

A new constructive and technological approach was developed for the efficient production of large-dimensioned, curved freeform formworks, which allows the manufacturing of single- and double-curved textile-reinforced concrete elements. The approach is based on a flexible, multi-layered formwork system, which consists of glass fiber–reinforced plastic. Using the unusual structural behavior caused by anisotropy, these glass fiber–reinforced plastic formwork elements permit a specific adjustment of defined curvature. The system design of the developed glass fiber–reinforced plastic formwork and the concrete-lightweight-elements with stabilized spacer fabric was examined exhaustively. Prototypical curved freeform surfaces with different curvature radii were designed, numerically computed, and produced. Furthermore, the fabric’s contour accuracy of the fabric was verified, and its integration was adjusted to loads. The developed textile-reinforced concrete had a high three-point bending tensile strength. Beyond that it was ensured that the textile-reinforced concrete had a high durability, which has been shown by the capillary suction of deicing solution and freeze–thaw test with a low amount of scaled material and a relative dynamic E-modulus of 100% after 28 freeze–thaw cycles.