formula recognition

[landrover77]

Gents

can someone give me a hint or two on the following please. I'm trying to work through some else"s calculations

i have a simple frame two vertical members, bridged at the top by a single Horizontal member.

Vertical height = h
Horizontal length = between vertical members = L
I1 = second moment of area for the vertical leg
I2 = second moment of area for the Horizontal
Load = P


the first formula, finds a ratio of second moment of areas x ratio of height to width

K = I2/I1 * h/L

Then K is used to find to dimensionless factors.

N1 = K + 2
N2 = 6K+1

the two N factors are then used in calcs to find moments.
eg; moment around ground level end of vertical legs. in vertical plane +PL/8N1
eg; moment around ground level end of vertical legs. in Horizontal plane -PH/2 * 3K+1/N2

I assume these factors just allow simplification of eqns, i'd like to see the derivation of these, its been a while since i've done any structural calcs, any help much appreciated.

thanks in advance

 

[paddingtongreen]

This looks like Kleinlogel. Your idea is correct. Simply expand them back into the formulae and you will see recognize the usual un-simplified versions of the formulae.



Michael.
Timing has a lot to do with the outcome of a rain dance.

 

[landrover77]

Thanks,

Reference is correct.
Steel designers manual appears to list his formulas.