Retractable Tensile Membrane Dome, France

Project Description

The structure consists of six movable arches, opening up the entire structure. The dome's first five arches are simple member elements, while the sixth element is designed as a three-dimensional truss consisting of five arch sections. To achieve an open dome position of up to 180°, two struts made of HEB 280 cross-sections, placed at each end of the spatial arch truss, are activated for rotation by two geared motors. This allows for controlling the opening and closing of the dome.

For this project, additional RFEM 5 models were created to analyze the welded joints of both the members of the three-dimensional truss and the struts with the geared motors, using nonlinear material behavior.

Structural Analysis

First of all, the form-finding process for the textile membrane was carried out on the entire model using the RF-FORM-FINDING add-on module. This way, it was possible to design the forces in the membrane and to dimension the structure.

In the second step, the steel structure's loading from the support reactions of the membrane model was applied in order to start the calculation according to second-order analysis with automatically generated imperfections using the RF-STABILITY and RF-IMP add-on modules.

Finally, the structural components were designed by the RF‑STEEL Members and RF‑STEEL EC3 add‑on modules. Furthermore, the RF-MAT NL add-on module was used to perform FEA calculations for the connections and anchorages using elastic-plastic material models.