Let me start by saying that I've really enjoyed going through your gallery. You have a lot of quality images, this one included.
As someone who likes to get feedback on my images in order to improve and/or see things I may not have thought of, I like to help out when I can. Also, since you asked for a "critique", I assume you are looking for something other than "great image!", as that type of feedback doesn't really help; the comments are for stuff like that.
That being said, I love this pose, the fact you made it b&w and the sharpness of her eyes, which really connect with the camera.
My only two "critiques", which are totally my opinion, so take them how you will, are a) that I would change the crop slightly to bring in more of her legs and bring her head a bit further down in the image, by coming out wider and/or changing the image ratio in order to make it a bit wider, and b) I would have shot this with a longer focal length than 50mm, maybe somewhere around 100-150, in order to compress the image, thereby reducing the size of her front hand. I like that it's there, but I find it a bit distracting because it appears larger and, because her arm is mostly hidden by the train track, like it's just sitting there and doesn't belong to her.