Ceramic Backer Bars on Full Pen Welds 2

[vgillespie]

Does anyone know of a good reference I could use to become more familiar with using ceramic backer bars in full pen welds in beam to column moment connections in seismic "zone 2" or Av=0.12?

 

[TowerEngineer]

A good source of information is Lincoln Electric. You can find them on the net. Your local weld material supplier (sales rep) should be very helpful in this regard. They are "in the business" and should have a vast amount of literature available for you.

Another good source is the American Welding Society (also on the net). AWS D1.1 permits the use of ceramic backing material but does not discuss its use or mis-use.

 

[HochwaltPE]

You might also take a look at FEMA-353 "Recommended Specifications and Quality Assurance Guidelines for Steel Moment-Frame Construction for Seismic Applications." It has at least a couple paragraphs discussing the use of non-fusible backing bars. There may be additional discussion in the FEMA-350 through 352 publications which also came out of the SAC research.

How seriously I would take these requirements in zone 2 would depend on what type of frame I was designing. If I were using the R value for a SMRF, I'd feel pretty strongly that I should adhere closely to the FEMA Guidelines. If I didn't, the building might not be able to sustain the degree of non-linear behavior assumed by my design.