# Steel Construction Manual



## Bigwolf (Jun 23, 2008)

I have been working some steel problems in both SERM (4th Edition) and also in "Seismic Design Review for the PE Exam" (6th Edition)--Kaplan book.

I have run into a couple problems involving tension connections and trying to determine the effective area. In both SERM (Pg 4-30) and "Seismic Design" (Pg 195) the author (Alan Williams) says that dh = db + 1/8" for use in the determination of the effective area......both books reference the Steel Construction Manual (AISC) Section D 3.2 and Table J3.3--&gt;however, when I go to these sections, the best that I can figure out is that the bolt hole should be 1/16" greater and not 1/8".

I'm just curious if the 1/8" is a flub that wasn't updated with the new version of the Steel Design Manual or if I'm missing something :reading:


----------



## kevo_55 (Jun 24, 2008)

BW,

I must admit, I only have my 9th and 13th editions infront of me but I think you have found an error in the SERM and Kaplan books. The standard hole is 1/16" larger in diameter than the bolt you're using.

Have you checked for errata for the SERM or Seismic 6th edition from Kaplan?


----------



## rdbse (Jun 24, 2008)

The net area for bolt holes in design should be taken as 1/8" larger than the diameter of the bolt. For punched bolt holes, the holes are actually 1/16" larger than the bolt; however, punching is assumed to damage 1/16" more of the steel around the hole.

See AISC 13th addition, Commentary Section D3, Part 2 Net Area.


----------



## Bigwolf (Jun 25, 2008)

Thanks for the responses....I see now how they get the 1/8"....seems like kind of round about logic but o well....

cheers. :beerchug:

http://www.ncees.org/exams/professional/pe...n_standards.pdf

One more question....referencing the above link to the Structural Design Standards for NCEES....does footnote #3 mean we can use LRFD for the 13th edition?


----------



## rdbse (Jun 25, 2008)

You have the option to choose between ASD and LRFD. I remember for SEI there are two columns of answers A through D, one column for ASD and one column for LRFD.

Also, back to the bolt hole question. Table 9-1 in the 13th Edition connection section provides the reduced area for bolt holes based on the plate thickness and bolt diameter. Basically, the diameter + 1/8" is factored into the table.


----------



## kevo_55 (Jun 25, 2008)

Holy crap, I didn't know that. I guess you learn something new every day.

Thanks rdse!


----------



## itsmemario (Jul 1, 2008)

I ran into this same exact problem when studying for the PE civil/structural test. Glad someone could clear this up. Thanks.

But I was looking through the AISC manual and came across this during my studying, Table J3.3 on page 16.1-105, Nominal Hole Dimensions; they give a chart for bolt hole diameters and it seems for a standard hole its 1/16". Please clarify. Thanks.


----------



## itsmemario (Jul 1, 2008)

itsmemario said:


> I ran into this same exact problem when studying for the PE civil/structural test. Glad someone could clear this up. Thanks.
> But I was looking through the AISC manual and came across this during my studying, Table J3.3 on page 16.1-105, Nominal Hole Dimensions; they give a chart for bolt hole diameters and it seems for a standard hole its 1/16". Please clarify. Thanks.


I think I got it...nominal = bolt diameter + 1/16" and design = nominal + 1/16", so total would be bolt diameter + 1/8". A bit confusing.


----------



## Bigwolf (Jul 2, 2008)

^^^^^^ lusone:

I completely agree


----------

