Peer relationships measurement Is there a method for measuring peer relationships in university students (e.g., a questionnaire)? 

I am looking for a questionnaire that can be used to asses the level of peer relationship among students. In other words, how students are able to relate to their peers.
Yes. This field of research is known as social network analysis, or SNA. It existed well before Facebook et al. hijacked the term.

Various resources will include sample questionnaires and the mathematical analysis applied (Networks: An Introduction was for me by far the clearest text on the mathematics of networks; a lot of books on SNA are off-putting once you get to the maths part).

You may also want to google for graph databases (eg, neo4j). I'm pretty sure I've seen a few examples of such analysis floating about.