In Reply to: SurePlate steel building connections WTC?? posted by JWmHarmon on January 08, 2002 at 10:45:35:
Regarding the steel connections- If I understand some of Ngon Nguyen's posts, part of the problem could be related to the visco-elastic couplings, where elements need to move relative to each other in order to compensate for building sway, etc, so a rigid joint would not work. The VE joint is illustrated in A, with the viscous "glue" in red. What Ngon pointed out was that this kind of glue will melt or burn up in a fire, so that the bottom chord of the truss is effectively disconnected from the column. I tried to think of some ways to "add" redundancy ; in B, bolts are somehow put through the three plates, with enough latitude to allow them to slide in normal operation but not separate. In C, a sleeve surrounds the entire damper assembly; and in D, a steel bar is formed and welded to both elements, to allow some "spring" action....