Static behavior of deployable cable-strut structures

• A foldable structure based on di-pyramid (DP) cable-strut unit was proposed.
• A prototype was designed and built to validate the concept.
• The mechanical behavior of this system in a fully deployed configuration was investigated.
• The effects of pre-stress levels, and temperature fields were studied.
• The influence of the cable loss was also investigated.

Deployable cable-strut structures are spatial structures that are composed of struts, active and passive cables. A deployable structure based on di-pyramid (DP) cable-strut unit was studied in this paper. Firstly, the concept of the deployable cable-strut system is proposed. Then a prototype is built to validate the concept. Then the mechanical behavior of this system in the fully deployed configuration is investigated. Finally, the parametric analysis is carried out to study the effects of pre-stress levels, the temperature field and the loss of cables on the structural behavior of the system. The results show that under the symmetric load case, the nodal displacements and axial forces of the struts and cables have a good symmetry. It can be found that the nodal displacements increase when the pre-stress factor is less than 2.0. Meanwhile the nodal displacements remain almost unchanged. The temperature changes have significant influence on the nodal displacements but have a little influence on the axial forces of the cables and struts. The loss of cables at the corner of the system leads to a mechanism. The cables of central DP units also have a certain influence on structural behavior in the sense that some nodal displacements and axial forces of struts change significantly after the loss of these cables.