There is no concrete evidence of his physical abuse but I wouldn't hold is past him. He used to be a raging alcholoic and has had many violent outbreaks according to various actors and directors.
From Aishwariya:"I stood by him enduring his alcoholic misbehavior in its worst phases and in turn I was at the receiving end of his abuse (verbal, physical and emotional), infidelity and indignity. That is why like any other self-respecting woman I ended my relationship with him."
Aishwarya has reportedly admitted that Salman's abusive nature and violent activities in the likes of creating scenes at her workplace or outside her apartment, forced her to walk away for good.