Determining undrained friction angle of cohesionless marine soils

[sway123]

Hi,
I am a mechanical engineer delving into the world of geotechnical engineering. I am using the Navy Civil Engineering Laboratory Handbook of Marine Geotechnical Engineering to determine the capacity of the soil to support a deadweight anchor. My problem arises when I try and determine the rapid cyclic bearing capacity of cohesionless soil. I have a buoy attached to the deadweight anchor that will impart a vertical uplift load on the anchor at a frequency of every 5 to 15 seconds. The Handbook states that "special cyclic undrained laboratory tests" must be run to determine the undrained friction angle. Other geotechs that I've spoken with say that the triaxial unconfined compression test isn't really valid for cohesionless soils because the sample is too easily disturbed. Does anyone know of laboratory tests, in-situ soils tests, or valid approximations for this value for marine soils?
Thanks for your help,
John

 

[ishvaaag]

I find this...

http://www.astm.org/Standards/D5311.htm

In any case any laboratory dealing with marine or coast soils may recommend how to proceed to get any data of interest to the problem.

 

[fattdad]

Tom Brandon at Virginia Tech can do cyclic shear testing. Give him a call or send him an email.

You can do triaxial testing on cohesionless soils.

f-d

¡papá gordo ain’t no madre flaca!

 

[sway123]

Thanks for your help.