Apply stress in 3DEC

Hello, I would like to ask question about how to apply a stress to a column. I have a column or block bar with 0.5m x 0.5m x 5m (x,y,z) as an elastic body. I would like to apply a triangular stress 3MPa at the top of the column for 0.02s, but I would like to make it as a point loading (apply in a coordinate) not an area loading (not apply to a block face). How can I set it ? Thank you.

Stresses can be applied on block faces & forces can be applied on block gridpoints.
Refer to the manual
http://docs.itascacg.com/3dec700/3dec/docproject/source/modeling/problemsolving/boundarystress.html?node2053#changing-boundary-stresses

If you don’t have a gridpoint at the location where you want to apply the point load, you can still do it with the BLOCK FACE APPLY POINT-LOAD command (see here: block face apply command — 3DEC 7.0 documentation).

Can it also be implemented in a old version of 3DEC (version 5.20) ? or Maybe it has another code for this version ?

This is in 5.2 as well. The command is BOUNDARY POINT …