Site Class Definition
Site Class Definition
(OP)
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
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





RE: Site Class Definition
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.
RE: Site Class Definition