Damaged Steel Column Capacity
Damaged Steel Column Capacity
(OP)
What references are there for determining the real-world, remaining column capacitiy for steel columns with damaged or dislocated flanges (ie: flanges bent mostly by fork truck impact)? We need to assess the stability and safety of an existing structure, and make provisions for any needed repairs.
Thanks -
David Anderson
Thanks -
David Anderson






RE: Damaged Steel Column Capacity
tubulars has been studied and documentad in offshore industry, and
used as well. Similar concept should be applicable for I-sections as well.
Basically, the procedure assumes that the dented/damaged portion is
ineffective in carrying axial load, computes the effective section properties
over the damaged region, and calculates the buckling strength. This
value is used in the interaction equations. This is not fully correct
for axial + buckling interaction, but is the best we have. This approach
has been used to evaluate damaged underwater elements,
strengthening which is very expensive, and should be avoided if
possible.
In case of land structures, I would box up the damaged region,
so that the original strength is nearly ensured. If the flange is very
severely bent, it is not effective anyway. The damaged piece can be
removed and a new patch-up piece welded in, before boxing up.
It will also safeguard the section against future forklift collisions!
RE: Damaged Steel Column Capacity
Additionally, the member should be protected either with ballastrades around the column or encase the column in concrete to avert further damage.
RE: Damaged Steel Column Capacity
If you encase the column in concrete to a fixity point above the damage, you really don't have to worry much about the damage affect.
RE: Damaged Steel Column Capacity
RE: Damaged Steel Column Capacity
We usually either encase with concrete or add new steel shapes to the old to provide an extended, stronger shape. This involves calculating a new set of section properties of the added steel with the "true" remaining cross section and ensuring that the new cross section has more stiffness and area than the original. In addition, the connection between the old/new steel should be looked at by ensuring that the full capacity of the new steel can be developed across the weld interface.
RE: Damaged Steel Column Capacity
RE: Damaged Steel Column Capacity
Caution for over-heating whenever an existing structure is involved. Provide shoring if you have to use a lot of welding.