Structural optimization of coreless filament wound components connection system through orientation of anchor points in the winding frames

Coreless filament winding is a technique where glass and carbon fibre filaments impregnated with epoxy resin are wound freely between two rotating winding scaffolds by a robotic arm. The load induction in the connections of coreless filament FRP components is one of the major challenges when designing with this novel structural system. An efficient fibre layup requires the fibre bundles to be aligned in the direction of the load, taking full advantage of the anisotropic characteristics of the material. In previous research pavilions developed at the University of Stuttgart, the direction of the fibres in proximity of the anchor points was mainly dictated by fabrication constraints (geometry of winding frame). The purpose of this research is to structurally improve the capacity of the connection system in fibrous building components. Load induction in several test specimens, representing different angles of incidence between fibres and winding frames, was investigated under tension and compression forces. Consequently, a computational tool was developed to generate winding frame geometries and optimal orientations of the winding pins (which allow fibres to lay in the direction of the load), and utilised to inform the fabrication setup for the prototyping and production of the components of the Bundesgartenschau 2019 Fibre Pavilion.