There are a couple of reasonable pictures of LNER coaling plants in the book Great Northern Engine sheds voulme 3 which covers Yorkshire and Lancashire. One pic of Ardsley one at Hammerton Street in Bradford both of which look virtually identical and two of Doncaster Carr,all 3 are mechanical facilities and from the pics appear to be concrete, the Doncaster ones give a good view of the wagon lift and the balance weights on the side to propel the wagon up to the hopper.
Alternatively the coaling plant at nine elms is maybe one of the best known.
Alternatively the coaling plant at nine elms is maybe one of the best known.