Support structure having alternative states of high strength or low thermal conductivity, and connecting strut

A connecting strut for connecting structural members having different temperatures, comprising:

• a support structure, the support structure including:
• at least one shaped component formed of a shape memory alloy, the at least one shaped component being configured to increase a strength of the support structure in a first operating state thereof and to reduce a thermal conductivity of the support structure in a second operating state thereof;
• a first strut structure;
• a second strut structure surrounding the first strut structure, the second strut structure having a higher mechanical strength than the first strut structure, the first strut structure being securely connected at least at one end to the second strut structure;
• and
• a holding device, the first strut structure being connected to the holding device, the second strut structure being releasably connected to the holding device by the at least one shaped component.