Signs of Collapse

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Across
  1. 2. Showing lines on the surface
  2. 4. Bent beams or floors
  3. 5. Steel stretches from original state
  4. 6. Give way under weight
Down
  1. 1. Suddenly fall down
  2. 3. A gesture to relay information
  3. 4. Falling stone work & mortar
  4. 6. A rounded swelling
  5. 7. Carries vertical load from floors