I don't think there is a word to express the melancholic fascination with megastructures, but I certainly suffer from it:
...the intricate patterns of stairs, windows, pergolas and cables, the chaotic and seemingly random arrangement of supports, the organic tumefying rust that de-patterns the otherwise perfect recursiveness...
it is the same feeling that makes one appreciate kowloon walled city and Tsutomu Nihei's superb early works, to give two examples