In RAM Concepts I have a shear wall core and when looking at the mat forces it seems that the forces are concentrated at the ends of the wall and not distributing along the wall. This is causing my shear reinforcement to be very high. Is there a certain way to model the wall? I imported the model from RAM SS. Are there certain slab modifiers for mat foundations? I am currently using two slab properties.
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You can see the loads that are applied. Nodal reactions are used for lateral loads from a wall on a mat. Line loads are used for gravity forces.
See also: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/4406/importing-items-into-ram-concept
Does Ram dump the loads at the ends as if the walls were pin -pin on the ends. Or does it break it up into segments. I would think that even for just D + L the distribution of forces would be more even under the walls.
I think that behavior is to be expected. The height of the walls and the size of the mesh are factors that could affect the force distribution. So too is the stiffness of the soil springs. Whether the stress spikes lead to a design issue depends on how wide the design strips are. I don't typically see slab modifiers used on mat slabs, but if cracking is expected then you certainly could apply them and the force would be further redistributed.