The phrase "to impose a structure" means to create or establish a clear system or organization in something that may not have had a specific order before. Full definition
Since my entrepreneurial life style doesn't impose structure on me, I have to impose it on myself, which daily habits do. (inc.com)
I personally believe that a church should never impose a structure of change on another. (nakedpastor.com)
An externally imposed structure, that dictates the nature of women's involvement in that structure, is likely to have limited success. (humanrights.gov.au)