Are there any calculation software of structural mechanics for ships?

I have no doubt that there are, but you’re not likely to gain a lot of insight into those in this forum. (But welcome to Fluther, anyway.)

ASME has pressure vessel calculation software, and other industries have software for calculating other engineering stresses on structural steel, concrete foundations, plastic injection molds – you name it. So I would only be surprised to find out if such software did not exist for the marine construction and maintenance industry.

I have no good idea even where to start looking for that kind of software, though. (And it might be the kind of software that is proprietary to particular builders and designers; not off-the-shelf software.)

@CWOTUS I just a student，my school is not buy the software，so I want to find a trial software

This site contains several free downloads.

http://www.bureauveritas.com/home/about-us/our-business/marine-and-offshore/marine/marine-solutions/marine-software