Site Class Definition

[kobys]

Hello,

Table 1615.1.1 in the new IBC code has the following definition to site class E:
Any profile with more than 10 feet of soil having the following characteristics:
1. Plasticity index PI>20
2. Moisture content w>=40 %, and
3. Underained shear strengh su<500 psf

the geotechnical engineer I'm working with say that if ANY of the conditions above exist than the site class is E. I think that the language is that if ALL of the condition exist than the site class is E. who is right?
please note the the definition for site class F has the following language:
Any profile containing soils having ONE OR MORE of the following characteristics: .....

Thanks,

KS

 

[JAE]

brave structural guy's attempt to answer it:

Upon reading 1615.1.1, it appears that the shear wave velocity is the key, and if you don't have that, then 1615.1.1 says you can use either N or su.

This is indicated in the first row of E parameters in Table 1615.1.1. The second row of E parameters indicates that any "profile with more than 10 ft. of soil having the following..." - so you would have to have ALL three to force you into a category E.

 

[emmgjld]

I believe the 'brave structural guy' has the correct answer.