Strusota
Structural
- Oct 12, 2012
- 1
This is a re-posting of thread that was posted in April of 2011. There were no responses to this original post. I have the same question that StuSE presented and I'm wondering if anyone has experience with this issue.
Thanks.
StuSE (Structural)
13 Apr 11 18:45
This sentence actually states for Nonstructural Component Anchorage(13.4), for Anchors in Concrete or Masonry anchors embedded in concrete (13.4.2) shall be proportioned to carry the least of the following:
13.4.2.a: 1.3 times the force in the component and its supports due to the prescribed forces.
Now....for the design of "Exterior Non Structural Wall Element" in Table 13.5-1, I have values for ap and Rp for both "wall element" and "Fasteners of the connecting system" The ap/Rp for the element is 1.0/2.5 = 0.4 ...and the ap/Rp for the fastener is 1.25/1.0 = 1.25. Therefore the seismic load for the "fastener" is 3.125 larger than for the "element".
Now 13.4.2 states that the anchors in concrete must be deisigned to support 1.3 times "the force in the component"....
so I'm wondering if this means 1.3 times the load I come up with for the "Wall Element" or 1.3 times the load I come up for the "fastener".....
It seems that I'm already designing the fastener for 3.125 times the load of the element, it seems excessive to add another 1.3 to it as well.
Note that none of the other listings in table 13.5-1 has numbers for the "fasteners" of the component.
I've checked FEMA 450 and can't find further info. I was hoping someone out here would have some insight or something else to point to.
Thanks.
StuSE (Structural)
13 Apr 11 18:45
This sentence actually states for Nonstructural Component Anchorage(13.4), for Anchors in Concrete or Masonry anchors embedded in concrete (13.4.2) shall be proportioned to carry the least of the following:
13.4.2.a: 1.3 times the force in the component and its supports due to the prescribed forces.
Now....for the design of "Exterior Non Structural Wall Element" in Table 13.5-1, I have values for ap and Rp for both "wall element" and "Fasteners of the connecting system" The ap/Rp for the element is 1.0/2.5 = 0.4 ...and the ap/Rp for the fastener is 1.25/1.0 = 1.25. Therefore the seismic load for the "fastener" is 3.125 larger than for the "element".
Now 13.4.2 states that the anchors in concrete must be deisigned to support 1.3 times "the force in the component"....
so I'm wondering if this means 1.3 times the load I come up with for the "Wall Element" or 1.3 times the load I come up for the "fastener".....
It seems that I'm already designing the fastener for 3.125 times the load of the element, it seems excessive to add another 1.3 to it as well.
Note that none of the other listings in table 13.5-1 has numbers for the "fasteners" of the component.
I've checked FEMA 450 and can't find further info. I was hoping someone out here would have some insight or something else to point to.
