Not a bad try at all.
Modelling is excellent, cant see any tesselation problems, the detail is all there nicely but there are a few things that could make this nice image more appealing:

It needs a little more sense of depth and darkness, try an ambient occlusoin pass along with some more detailed diffuse and specular map corrosponding with the rust nicely.

Differenciate the textures a little more the floor and walls feel a little simmilar, get some reds into the rust and some muddy and dull cracks into the walls, damp into the celing.
Other things that would help is volumetric lighting an maybe bring some of the details closer to foreground, it seems a little flat and exclusively mid-ground.