HR exists to protect the company. When you raise a problem to them, you are the one responsible for the problem being put on record. This means you are the problem. Even if you go to HR and they do something about it, you still lose because your coworkers will steer clear of you for being a narc and any chance at a career is pretty much gone. Either work the problem out with your coworkers yourself, ignore it and keep your head down, or find a new job.