It was not known how long the exclusion would last, she said.
"Some students may appeal the decisions. No further comment can be made until the appeals process is complete."
Proctor Dave Scott said the university was not opposed to students having fun, but was concerned some ill-conceived and poorly thought through events like flat initiations, may pose significant risk of serious harm to participants, both mentally and physically.
"For this reason, the university will do everything in its power to keep students safe, while providing them with a world class education."
He said work to address the issue began in 2017 and would continue this year.