Fab painting ! Great concept too.
A few pointers to make it better - although I hate to dare suggest:
The holes in the cement / stone would be a lighter colour, not red brick colour.
If the tanks runs on dusty ground, the track pads would be dusty too - it wouldn't rub off.
There seems a disconnect between the red brick rubble - and specifically the lighter dust on the road. Perhaps add some odd brick pieces on the cobbles, and / or lighter dust on the bricks?