Boiler Steel Column Bent/Allowable Value 2

[pootong]

Steel structure for boiler column is bent after erection, it can be seen by our eyes. After measurement, it is clear that the column is offset at mid span between bracing points about 15 mm. Distance from one bracing piont to the other is 6,000 mm. It is stated in AISC that allowable off set is 1/1000 that means only 6 mm. Could you give recommendation on this issue how we fix this problem.

 

[SlideRuleEra]

One way to start is to compare the design column load with the allowable load for an undamaged column. Often industrial structures have robustly sized members to allow for "unexpected" events.

The ratio of design load to allowable load will determine your next step. If the column is "lightly" loaded, perhaps you don't need to do anything. At the other extreme, column replacement may be necessary. The answer is probably somewhere in-between (perhaps additional bracing). In any event, I suggest an orderly, step-by-step approach.

http://www.SlideRuleEra.net

 

[SlideRuleEra]

I neglected to mention a very important intitial consideration:

What caused the bend? Will this event/condition happen again?

Perhaps the design is the problem.

http://www.SlideRuleEra.net

 

[pootong]

The column is intially bent after struture was erected without any load. May be it's already bent after fabrication or from the steel mill. Thanks SlideRouleEra.

 

[flamby]

Steel members sometimes get bent during erection due to improper handling or lifting. Sometimes the same thing happens during transport where such beams are kept in the trailor "simply supported" and stacked one over the another by some ignorant transporter.

To check its current status, do what SlideRuleEra has advised.

You can also try to find out if there is any steel straightening agent in your area. They may also tell you whether use of heat or flame is advisable.

Ciao.