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glass block anchorage

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I'm looking for some input on the anchoring of glass block wall panels. 
I am working with a group of architects who feel that using steel
channels along the top and sides of the wall panel will detract too much
from the architectural statement of the building.  UBC section 2110
clearly allows the use of "panel anchors" to anchor glass block, but
also requires that the panels be anchored for a minimum load of 200
lbs/ft.  I am having trouble quantifying the allowable load for these
anchors (as well as satisfying myself that a light gage metal strap
perpendicular to the direction of the load can provide a positive
connection).

I have spoken with members of ICBO, the International Masonry
Association, The Masonry Association of California, and Pittsburg
Corning in regard to this issue and still have nothing definitive.  The
best and most relevant information I received from Pittsburg Corning was
a copy of some testing which was performed on some 12 ft square glass
block panels anchored to a frame with panel anchors at 16 inches on
center on both sides and across the top.  The panel was loaded with a
constant pressure by inflating air bags on the face.  Failure of the
panel anchors was recorded at a pressure of 60 lbs/sq ft.  It has been
my experience that a safety factor of 4 is ordinarily used on ultimate
failure loads such as this. That would leave me with an allowable design
load of 15 lbs/ sq ft which may meet wind and seismic criteria, but will
not meet the requirement for anchorage in the code -  even if I double
the anchors to 8 inches on center.  Am I applying too great a safetly
factor? 

Any comments or advice? 

Karen E. Casano, CE
Biggs Cardosa Associates
San Jose, Ca.