This kind of rupture has a very unpredictable shape, depending on material structure, etc... so there is no way to emulate it properly using SU. BUT... you can use a image (photo) to guide yourself in doing the shape or that rupture. Then, using the same image as texture, apply it on that piece. Just build the wall as you would normally do in reality and use real-life photos to guide you and to create textures. Best would be for rendering to use a rendering engine that support Displacement Mapping, so you will be able to create richer surfaces that way.