97 UBC Code Duration Factor Question

[SIEVERT]

Table 2.3.2-Load Duration Factors on page 2-291
I am designing anchor bolts for a sill plate connection to the concrete foundation wall for lateral analysis. For the wind load duration factor, when can you use 1.6 as specified on note 2.

Thanks

 

[DVM]

As the note states, 1.6 factor may be used for Mode III or Mode IV behavior. You have to check your sill plate for the controlling behavior per the NDS dowel bearing equations (single shear with concrete main member). Typically for sill plates the failure mode is IIIs and the 1.6 factor may be used.