I sent a similar message to the list yesterday, but only received one
response. I am still confused. No offense Ben Yousefi, I did very much
appreciate your input, I'm just still confused. Now somebody has got to
understand this code and be able to explain it to an average engineer like
Some background, I thought 1997 UBC took care of the change from ASD to USD
through the R factor and other adjustments. I don't understand why Equations
30-1 and 30-2 are there. Do they apply to all designs?
Equation 30-2 multiplies Eh by the omega factor. I am designing a concrete
SMRF structure. Omega is 2.5. Therefor Em is equal to 2.5 Eh, which I
believe is the base shear. So does this mean I multiple the base shear by
2.5 for my member design? If I am running load combinations in my frame
analysis, do I add this factor to the combinations? It seems I am increasing
the shear quite a bit, although it was already suppose to be at strength
Any insight into this would be helpful.
Richard Lewis, P.E.
Missionary TECH Team
The service mission like-minded Christian organizations
may turn to for technical assistance and know-how.