How to add traction boundary by supplying pressure?

Rodgers · Post by **Rodgers** » Sat Jan 26, 2008 9:46 am

I come to OpenSees as a FEAP user and want to use OpenSees to do some solid structure modeling, not just beam column.

I miss the ability to add patch loads and add constraints by supplying edge etc.

In case it is not listed in the online manual, does OpenSees provide a way to specify traction boundary by supplying pressure like "CSURface" in FEAP? In other words, is there a command that will compute equivalent nodal load based on pressure on a element surface? Better yet, could it find the right element to apply the load automatically?

If not, which element routine should I call to add this capability when coding it?

Rodgers · Post by **Rodgers** » Sun Jan 27, 2008 10:17 am

Looks like eleLoad has similar functionality, but is limited to single element and beams only.

silvia · Post by **silvia** » Mon Jan 28, 2008 8:42 am

i have no experience with the 3d elements. however, i think you have to calculate the equivalent nodal forces -- which is what feap does anyways.

Rodgers · Post by **Rodgers** » Tue Jan 29, 2008 12:15 am

Thanks Silvia!

I was thinking an element should be able to know how to do the N(x)Tau(x)ds integral. I just need to ask all the element that has edges aligned with the supplied conditon to provide the equivalent nodal load. And then use the "load" command to actually add these nodal loads.