PSI - Issue 63

Dominik Gřešica et al. / Procedia Structural Integrity 63 (2024) 7– 12

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2. 3D printing and membranes 2.1. Micro scale model

In the example presented here, a way is used where 3D printing is gradually applied to the above-mentioned solution of specific details of membrane structures. This phase involves the preparation and application of small models of membrane structures in which 3D printed fasteners are applied (Fig. 1), which allow the specific unconventional shapes of the fasteners to be taken into account with regard to the stress demands at the connection detail points, particularly due to the high tensile forces that arise at these points. The cost-effectiveness of 3D printed joints for structures with complex details and loading patterns is particularly evident in cases of non-repetitive details where each joint is unique. Otherwise, with multiple repetitive details, it is advisable to consider, for example, the use of 3D printed moulds for the subsequent casting of fasteners.

Fig. 1. Prototype of joint of the membrane to the support element made using 3D printing in scale approx. 1:100.

2.2. Macro scale model The concept of creating small physical models is then only a step away from application to larger models (Fig. 2). However, this step brings with it a number of challenges and unknowns that must be considered. The primary complication is the size of the joints themselves, where there is a limit to the print sizes. In the context of small reference models, it is possible to consider joints as one-piece units. In the case of application to large models, the divisibility of the connection into individual parts must already be addressed, due to the limitations of the 3D printer's print area and the subsequent joining, for example by gluing (Fig. 2 (b)) or mechanical fasteners. This fact brings with it a significant difference in the assessment of the behaviour of