Sye,
You have a very informative presentation in how to model a plate support, now I would like to know exactly the difference between the foundation support vs. the fixed but support for a plate or mat foundation, especially when modeling a slab on grade or grade beam.
Regards..
Hazim
The main difference between a foundation support and a spring support defined using the FIXED BUT option is that the former calculates the spring stiffness based on inputs like subgrade modulus and influence area associated with the nodes whereas the later requires direct input of the spring stiffness values by the user. If you are modeling a mat using a mesh of plates, it would be the easiest to use the PLATE MAT type support ( available within Foundation support )
Which one is better off for grade beam modeling?
Thanks again for the informative You Tube presentation.
You are welcome. I assume you have modeled the mat using a mesh of plates and the grade beams using beam elements. If so, the grade beams would be split into segments by the plate nodes and these nodes are going to be the point of connectivity between the plates and the grade beams. If you assign PLATE MAT support to the plates, the software would calculate the springs at all of these node points which are going to act as common supports for the mat and the grade beams.