Is it ever discussed or revealed if Cardassians are generally stronger than humans? I would think they are since humans seem to be pretty weak when compared to many other races (klingons, vulcans, etc.) Where do the Cardassians rank in physical strength?
Within the TV show, there aren't any specific conversations about Cardassian physical strength, nor are there any special mentions in the general reference material about the Cardassians being stronger or weaker than humans (or any other race, for that matter).
There are numerous scenes of the Cardassians in fights with humans. Sisko punches Dukat, Dukat is dragged from his office, Sisko punches Garak, various guards are beaten up by Federation soldiers, etc etc. In each of these encounters, the Cardassians show no overt physicality, all of which tends toward the the conclusion that their physical strength is unremarkable by human standards.
Moving down the canon scale, within the EU the Cardassians are generally portrayed as having no exceptional strength. The Cardassian RPG sourcebook gives them no additional points for strength compared to human-normal and the various novels make no reference to their strength.
in "Emissary", O'Brien fights a Cardassian and is pushed backwards by a Cardassian soldier:
Movement: a black-sleeved arm sweeping across his field of vision, knocking the phaser from his hand. O’Brien reached out blindly, seeing nothing now but rage and hate, and caught one of the Cardassian’s wrists, then the other, roaring as he slammed the alien into the wall. The air rushed from the Cardassian’s lungs with a loud gasp. O’Brien seized the hand that held the phaser, pinned it against the wall and then slammed it again and again, until the weapon clattered to the floor.
With a surge of strength, the Cardassian pushed. O’Brien staggered backwards, stumbled over a wailing child, and lost his footing. The Cardassian scrabbled for his weapon.
In the Mirror Universe Novel "Shards and Shadows", Keiko is pushed and lifted by a cardassian guard. There is no mention that she's surprised by his abilities:
A Cardassian guard she knew by sight but not by name reached down to grab her arm. He pulled her to her feet. Keiko got her legs underneath her and used the Cardassian’s arm to help steady herself.
The Cardassian pushed her against the wall. “Explain yourself.”
He pushed her against the wall and kissed her. She responded by dropping her tools and wrapping her arms around his neck. She leaned into his kiss.
They never say, although Cardassians seem to be much weaker than Bajorans - Kira, a 90-pound Bajoran female, is able to kick the asses of at least a couple different male Cardassias. And those were soldiers, not a tailor - Sisko kicked Garak's ass. Since Bajorans were never shown to be any stronger than humans, I assume a human is also much stronger than a Cardassian.
There is a scene in DS9, where humans are described as having superior auditory abilities... we also have a higher tolerance to cold opposed to Cardassians and Vulcans.