Dodecahedric mutually supported element space structure: Experimental investigation

Circuits of mutually supported elements (MSEs) can produce novel 3-dimensional spatial structures. In the creation of a circuit, the basic concept is that the primary members rely on each other for support. These novel structural arrangements may give rise to complexity in the configuration geometry and structural behaviour due to the creation of an eccentricity between elements. An experimental programme was designed to aid understanding of the primary behaviour of structures composed of MSEs. This investigation concentrated on the structural performance, under applied static loading, of a dodecahedric MSE space structure. The main objectives of the experimental investigation were to confirm behaviour as being linear elastic within a predermined appied load range, to understand the distribution of stress and the displacements of the structural elements, later to be compared with that predicted by numerical modelling. Displacements of closed MSE circuits with different spatial orientations were considered. Differences in the recorded strains were also considered. The experiment highlighted the difficulties associated with monitoring MSE circuits, particularly support stiffness and displacements of circuits with arbitrary 3-dimensional spatial orientations. The recorded strains were complex in nature in as far as they included the effects of axial forces, bi-axial bending, shear and torsion. It was found that the maximum applied load did not cause yield of the material according to the von Mises ductile material failure criterion