Resource for design of washer plate connections to wood

[SparksRfun]

I'm looking at determining the strength of a bolt with a washer connecting a wood bottom plate to concrete. Code in high wind or seismic areas typically dictate a square steel plate of a certain size in some cases. What resource (charts, formulas) can I use to find the capacity of such a connection given a known bolt size, washer size,and wood species? Is this information somewhere in the NDS?

SparksRfun

"The truth will set you free, but first it will make you madder than a wet bobcat"

 

[DaveAtkins]

Are you concerned about shear, uplift, or both?

I have found if you try to design a washer for uplift by checking bearing perpendicular to grain, NDS will give you a very conservative value. I think this is because the bearing perpendicular to grain value in NDS limits deformation, not ultimate failure. I think the ultimate uplift capacity is more accurately determined by checking punching shear through the wood sill plate.

DaveAtkins

 

[SparksRfun]

@Dave Atkins, yes we have to check for shear and also for uplift. I am trying to learn how to do this, and do not know how to use the NDS to check for bearing perpendicular to grain. Maybe that is where we need to start? How is that done generally? In general I am attempting to blunder my way through learning this subject, without much guidance, and this particular exercise is not going on any plans, just trying to learn how it is done.

SparksRfun

"The truth will set you free, but first it will make you madder than a wet bobcat"

 

[lexpatrie]

For lateral load, there's a Table in the NDS, Chapter 12, i think.

 

[DaveAtkins]

Start with Table 4.3.1 in the NDS. It is for sawn lumber, and it gives the formulae for the various design values.

DaveAtkins

 

[ChorasDen]

Years ago I made this flow chart to try and understand the requirements for shear walls anchorage in SPDWS. The provisions in the NDS are intended to limit cross grain bending.