Good Day Everyone,
I wish to analyze and design an underground cistern (tank) using STAAD Pro. However, I would like some advice as it relates to the supporting conditions for the base plate. Based on my idealization I used plate meshes to form my surrounding walls, and the top and bottom slab and I considered the base as a mat/raft foundation, as such I used the foundation support in STAAD. I have the following queries:
1. Is this an accurate foundation option to analyze an underground tank?
2. If the tank was on the surface would this foundation be suitable as well?
3. Example 10 in the application examples uses pinned supports, why was this done rather than fixed supports or the use of the foundation supports?
4. Will the use of the foundation support accurately represent the upward pressure reaction of the soil when the loads are applied to it?
I have attached the model for inspection
Thank you.(Please visit the site to view this file)