Conversation so far:
What was the tube structural system?
The exterior wall perimeter of a building simulates a thin-walled tube to resist lateral loads such as wind forces and seismic forces.
Did tube structural system do well?
Fazlur Rahman Khan's tube concept revolutionized tall building design. Most buildings over 40 stories constructed since the 1960s now use a tube design derived from Khan's structural engineering principles.
Was the tube structural system used for anything else besides buildings?
No, the tube structural system was not used for anything else.
Was there anything else interesting about the article on the tube structural system?
The tubular systems have yet to reach their limit when it comes to height.

Question: What else can you tell me about the tubular systems?
Self-contained rewrite: What else can you tell me about the tubular structural systems besides height limitations?