I want to study the motions (in Moses) of a long and hollow box standing vertically on the seabed. The box extends throughout the water depth and has a small portion extending above the water surface. The base of the box is heavy and is simply resting on the seabed. As this body is in contact with seabed (not floating), the weight of the box is larger than its buoyancy.
I want to know,
Hello, In MOSES a body can be modeled as a rigid body without any motions, one can turn off all degrees of freedom for a body that makes it "fixed". Another approach is to apply a generalized spring connecter and give high stiffness values to simulate a "fixed" body. If the body undergoes rigid body motion in response to environmental loading then the seabed can be modeled as foundation that applies contact forces when the body comes in contact with the seabed. I hope this is clarifying