Plate area Load in SACS


Product(s):SACS
Version(s):23
Area:SACS IV

Problem

How can I apply plate load in a SACS model and then transfer it to member load, in similar analogy with Staad.Pro Floor Load?

Solution

There are a few different ways in which a plate load may be applied to the structure.

The options are:

1. Distribute to corner joints

2. Centroid (Space Load)

3. On plate

The first two options in my experience produce the same results. 1/4 of the total load (for quads) is distributed to each node as a joint load. With the third option, the internal loads are calculated for the plate due to the pressure and those end forces are distributed to the corner nodes. So, with the third option you will actually get moments at the nodes due to the internal loads in the plate. None of these options will result in loads being distributed to members. The plates are always connected to joints.

The only way to distribute loads to a beam framing a plate would be to do as model the load as a member area load. There is an option to distribute the loads in both the local x and y directions of the plate which should produce a similar result to the FLOOR LOAD command from Staad.Pro.