No Cap and Base Plate

[jjeng2]

I am designing a modular structure that will be assembled in the factory. Its a small 15X20 box. Typically, they weld all the steel directly to each other. I dont have a problem with welding filler beam webs directly to girder webs but...they weld the tube columns directly to the top flange of the beam below and the bottom flange of the beam above. Is there any specific AISC requirement that requires base and cap plates? Is there an analysis procedure to check bearing with no plates?

Also, the structure needs to be designed to be lifted from lift points. Any advice on that?

 

[swmiami]

If Special Design Considerations in ASD Chapter K are satisfied, I don't see a reason that cap/base plates have to be used.

ASD Section A4.2 specifies minimum load increases due to impact. Building codes should have similar provisions.

 

[jike]

Cap plates and base plates are typically specified to:

1) Spread the load out

and

2) To provide a bolted connection to fasten the column to the beams

If bolting is not required and you can satisfy bearing and web crippling requirements, then no cap plate or base plate is necessary.