Hello. I'm in the middle of a project to convert my crawlspace to a basement. I will be replacing 5 masonry columns with steel pipe columns. Per my engineer's recommendations, I am using nominal 3.5" schedule 40 pipe (4" O.D.). So far I have welded the top plates to the pipes, but will be waiting until everything is in place before welding the baseplates. One thing I would like to do is fill each column with concrete. My reasoning is that it would take so little concrete to do this, and the strength increase so significant. However, I'm wondering if doing this with one side of the pipe already sealed up would trap any excess moisture from the concrete and rust my pipes out prematurely. Anyone have any thoughts on this? Would it be enough to leave one end open for a few days while the concrete sheds excess moisture? I do plan to grind a couple of notches on the pipe bottom before welding the baseplate to serve as weep holes, but with a pipe full of solid concrete I'm not sure what difference that would make. Thanks in advance for any input.