Friday, May 18, 2007

RE: Backing bar in RBS steel moment connection

As usual excuse my ignorance, but why only the bot. flange?
 
MB
-----Original Message-----
From: bart@nbse.com [mailto:bart@nbse.com]
Sent: Friday, May 18, 2007 11:47 AM
To: seaint@seaint.org
Subject: RE: Backing bar in RBS steel moment connection

At the beam bottom flange, the backing shall be removed.
 
At the top flange, removing the backing is optional. (continuous attachment to the column with a fillet weld is required)
 
My opinion is that leaving backing bars in place is a poor idea, however, it is often cost prohibitive to remove them, backgouge and backweld with a reinforcing fillet.

----- Original Message -----
From: "Gautam Manandhar"
To: seaint@seaint.org
Subject: RE: Backing bar in RBS steel moment connection
Date: Mon, 7 May 2007 14:55:31 -0700

List members:

 

In a RBS steel moment connection, the expected plastic hinge is at the reduced beam section.  How important is it to remove the backing bar at the beam-column connection?  I am aware that in the pre-Northridge, fracture initiated at the bottom CJP joint.   Is anyone aware of tests done with the backing bar in place.

 

Gautam

 

 



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