25% Increase

[MOOK]

According to ASCE 12.3.3.4 page 125, we should increase the design force by 25% due to irregularities. Does Diaphragm nailing with shear walls (boundary nailing for example) is applicable to this 25% increase in the design force.

Thanks

 

[kevo_55]

I guess I'll take a stab at this one.

No, boundary nailing isn't applicable for this 25% increase. This increase is only for shear wall/moment frame to diaphragm connections and collector connections.

A good example of this can be found on example 7 of the 2006 IBC Structural/Seismic Design Manual (volume 1).

I hope this helps!

 

[MOOK]

I guess I'll take a stab at this one.
No, boundary nailing isn't applicable for this 25% increase. This increase is only for shear wall/moment frame to diaphragm connections and collector connections.

A good example of this can be found on example 7 of the 2006 IBC Structural/Seismic Design Manual (volume 1).

I hope this helps!

Thanks Kevo for your reply but is not boundary nailing part of the shear/wall diaphragm connection?

 

[kevo_55]

Mook,

Boundary & infill nailing is simply what is holding the diaphragm together. The connection to the shear walls or other LFRS is something else.

 

[greatjohn]

My understanding is here:

this 25% increase applies to diaphragm to vertical elements. diaphragm includes panel and its supporting framing members. Normally, panels are nailed to end blocks, and then end blcoks are nailed to supporting top plates below it.

The connections of end blocks to top plates shall include 25% increase.

 

[MOOK]

Thanks Guys for your answers

I think the following should be increased by 25%:

1-The connection between end blocking and inner blocking to the top plates

2- The connection between top plates and shear wall studs.

3- Boundary nailing above shear walls. Any boundary nailing does not connect the diaphragm to shear walls shall not be increased.