Vocabulary for a survey

I'm looking for a vocabulary to RDFize a survey
A look at lov doesn't gives anything significant
I've walked around the web without success
DDI-DRF doesn't seems to map on my case which is:
i have a lot of CONTRIBUTION in the survey
each contribution is
* related to one user -> foaf
* has one or several questions (which are just label in several langages
and list of possible values)
* has one or several answers, each one relate to a question and has a value

Nothing more.
Is someone having advices?


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Jean-Claude Moissinac
Telecom ParisTech