Uintah, from the University of Utah is open source and quite powerful.

http://uintah.utah.edu/

Another one, smaller is here http://people.oregonstate.edu/~nairnj/

Uintah can model the water-structure dynamic interaction using MPM or MPMICE but currently there has not yet option for soil-water interaction (under development).

Nairn MPM is powerful if you want to model the cracking.

Dear All

Thank you for your responses,

Vasudeo Chaudhari

This one is for soil. https://www.cb-geo.com/research/mpm/

All the suggestions here are good, but the best choice for you will depend on the details of your problem. Do your soil-water and water-structure interactions include porous flow? Failure of the solid through fracture? In what flow regime is the fluid? e.g., can it practically be modeled with MPM particles, or do you need a hybrid method like MPM-ICE where the fluid flow is an Eulerian field?

https://www.researchgate.net/post/Which-softwares-are-available-for-Material-Point-Method

Another one, Karamelo, details here https://www.researchgate.net/publication/344346650_Karamelo_an_open_source_parallel_C_package_for_the_material_point_method?_sg=cyjApULM7NQ2ieQvr59cy2PPAOtdLg80ExZ2u1XykhY2l3fSCi-jMTzDNhTtnjx1rKT_26hrTPY9ApheC_H7glJMfUc9Qe4ypUgZbgbq.W0IkCj1-w7e3qdgPO6qMcTEeokPWRslcftvK6PEGj9OYwrPOf00jNBD8iwCZqV3c6AfleSevMJwC6XE4_MAMZA

only solid mechanics problems with explicit time integration, but both total and updated Lagrangian formulations.