A bridge rebuilt for soldiers (7)
I believe the answer is:
brigade
'for soldiers' is the definition.
(I've seen this before)
'a bridge rebuilt' is the wordplay.
'rebuilt' indicates anagramming the letters.
'a'+'bridge'='abridge'
'abridge' with letters rearranged gives 'BRIGADE'.
(Other definitions for brigade that I've seen before include "Corps" , "Army grouping" , "Military group" , "Army unit" , "Company" .)