RISAFoundation FAQ
Common support and usage questions.
RISAFoundation
I get an error stating that the solution could not converge. What does this mean?
RISAFoundation models the soil as a grid of compression-only springs. Because it uses an iterative solution, it can sometimes have a problem converging on a solution since the slab tends to rock back-and-forth by very small amounts on each successive iteration. This can usually be solved by increasing the Maximum number of iterations in the Global Parameters. This could also be an indication of an overturning instability in your foundation.
How can I see my soil bearing pressure displayed graphically?
Go to Plot Options (Under the View Menu). On the Slabs tab select Color Fill with Contours as the Color Basis. Below, in the Contouring Control, select Soil Pressure.
How can I model a slab that has varying thickness?
You can draw the slab as multiple slabs with different thicknesses. As long as the slab edges are co-linear they will be considered fully connected.
How wide should I draw my design strips?
There is no easy answer to this question. The slab moments and shears will be averaged over the width of a strip, therefore unless a slab is uniformly loaded and acts rigidly, defining your strip as the entire width of the slab is ineffective. Much like the principle of column strips and middle strips for elevated slabs, it is important to define strips as having a width equal to that which the forces would naturally distribute over.
Structural Engineering Software, Structural Analysis Software, Structural Design Software
©2010 RISA Technologies, LLC. All Rights Reserved.
949.951.5815 | E-mail RISA Technologies, LLC | Privacy Policy