Digital path towards Timber Reciprocal Frame Structures

A.P.H.W. Habraken, T.S. Godthelp

SIDstudio b.v.

Reciprocal Frames (RFs) are structures that are feasible by means of circulating shear with compression or tension interactions between their constituent members. Beams do not meet at their ends but somewhere along their length. RFs can create planar to complex 3d surfaces. 3D shapes will increase the level of geometrical complexity drastically. When using straight elements the curvature is created by using stacked connection details. This results in a large variation of details regarding angles of intersection, profile dimensions and forces to transfer.

To date, an RF form finding tool that regards both beam depth analysis and the structural design of connections has not yet been developed. Although researchers developed computational form finding methods to create geometrical solutions and described the global structural design, computational complexity may have prevented a direct inclusion of detailing in the overall RF design. This paper presents a digital path from design to production for RF structures. A new RF form finding method is developed that includes both the structural design of beam dimensions and detailing and results automatically in production files for each element. This parametric model - named 'Reciprocal Frame Designer' (RFD) - has been developed to design RF assemblies of wood from any arbitrary shape.

Key words: Digital technologies, reciprocal frame, timber detailing, free form, form finding, computational design, design to production