Here is link to interesting document -
link
and here are some graphics:
Descriptions about pressure:
Document and graphics are about "Underwater explosion on a
ship" - not submarine but i think it gives us some good reference.
It shows that 210 kg of TNT can't sink ship from distance 120-180 yds. In other hand, your damages was
not massive. I think they responds 2-6 MPa.
I can't find information how strong nuclear warhead had shkval, but i think nuke explosion from that distances should sink your sub immediatly.
Conclusions:
- In RA shkval does little too powerfull damages from distances 120-180 yards but i think it is acceptable for "game purposes".
- damages you took definitely was not from nuke warhead