Structural Engineering Ref. Manual 4th

[hp32si]

I must be overlooking something but in example problem 6.5 on page 6-9 2nd column 14 lines up from the bottom--It shows an Transformed moment of Inertia of 7660 in^4----I cannot get my calculations to equal that? Any help--Please---I feel real stupid right now!

 

[deviationz]

I think it is the following:

bd^3/12 = 15.625* 15.625^3/12

2 * Ast * (d/2)^2

2 * 50.2 * (10.37/2)^2

It adds up to 7666 in^4

 

[hp32si]

Thanks--for some reason I was using the full dim. of 10.37" and not setting the axis at the mid point between the #6 bars. I must have gone on a mental vacation!

I think it is the following:bd^3/12 = 15.625* 15.625^3/12

2 * Ast * (d/2)^2

2 * 50.2 * (10.37/2)^2

It adds up to 7666 in^4