P-S Logging Test and alternative

[kaynakve]

Hi,

For a tunnel construction we are drilling boreholes and want to perform P-S Logging tests. However, due to some reasons we can not provide P-S Logging instrument.

Does anyone have any idea which other test(s) can be performed to get values comparable to the values that could be taken from P-S Logging?

If there is a way to evaluate the results to P-S Logging test results in a high accuracy, that will be the best.

Thanks for any advice

kaynak

 

[coneboy]

Hello kaynakve

I believe some text books and papers have been published on this subject.

You should be able to get an rough estimate of the compression wave velocity from some of the published literature. You will also need to review the core from the bore hole to fine tune your estimate of the shear wave velocity profile. Please remember that what you are attempting will be a rough estimate.

A couple possible alternatives.....
Can you set some PVC casing installed in any of the boreholes?
If yes, then grout in a PVC casing then lower a triax geophone down the hole. Many GeoPhi contractrors have tools that can measure S and P wave velocities using a cased hole.

If the brorehole is not accessable then you could try using SASW. SASW would enable you to get a better idea of the shear wave velocity, especially if you already have a core.

Hope this helps some

Coneboy