Hi Everyone,

Good Morning

I am new to geotechnical engineering.

My SI company told me that they won't take any UD for hard soil as their equipment hydraulic pressure is not high enough and their normal Shelby thin wall sampler is not suitable for hard soil. They also didn't use the cleaning bucket to clean the base, they said water pressure is aldy good enough to clean base before taking the sample. Is that a problem?

My understanding of samplers

(1) Shelby thin wall sampler - Suitable for soft soil and use hammering or hydraulic pressure to push sampler into the soil.
(2) Thin wall piston sampler - Suitable for soft soil and hydraulic pressure to push sampler into the soil. can get better samples compared to normal thin wall samplers due to the suction developed.
(3) Rotary sampler - Suitable for hard soil but do we still use the same equipment used for drilling to rotate the cutting bit?
(4) Mazier sampler - Same as a rotary sampler?

Do you guys usually do lab tests on hard soil? Will it be too much if I insist my SI contractor to do it?

Thanks