Old wood values

[structural2010]

This is my first post.......I see alot of posts and it seems like everyone helps alot.

I am recently out of college (one year). I work in the Chicagoland area.

I have been involved with alot of resendtial homes where the wood is almost full size (i.e. 1 7/8" x 9 5/8") therefore I assume the wood is pre 1950.

Do anyone know where I can find pre 1950 wood values (Fb Fc E)???

Some of the homes are we do are really old (1890, 1900, 1920)

Thanks

 

[msquared48]

Check out this thread:

thread488-197341

Sliderule's website is a tremendoue resource for all of us.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[woodman88]

Please be aware that the current NDS wood formulas are not compatible with the old (pre 1991) wood values.

Garth Dreger PE
AZ Phoenix area

 

[structural2010]

msquared48.......i have seen sliderule's posts before and are very helpful...Thank you!

woodman88.....that was one of my assumptions that the current formulas wouldn't apply......Thank you!

 

[RARWOOD]

The problem you are facing presents an interesting challenge. The design values you are looking for are only useful if you know the grade of the orginal material. You will also find that as you go back in time, you will start to find material that was never graded.

What I do is try to estimate the grade of material using a current grade rule book. My estimate is based on the size of knots, slope of grain, splits and other characteristics. If all four sides are visible you could have the material graded by an expert grader (which I am not). When only three sides are available you can only estimate the graded because you can't see the fourth side.

After estimating a grade I use the design values in the current N.D.S. applying at least a load duration factor of 0.9.