shear modulus and shear wave velocity of soil

[Hanii]

I have to model foundation springs for soil structure interaction. what are simplest soil tests (that may available in UET Taxila) to find out shear modulus and shear wave velocity.

[UmarMakhzumi]

Hello Hanii,

The simplest soil test the can be  done is Standard Penetration Test (SPT). Published academic co-relations can be used to determine shear wave velocities and shear modulus of different soil layers against SPT N values. UET Taxila is able to do SPT test.

The preferred method to get shear wave velocity and shear modulus would be Cone Penetration Test. Its the most preffered field testing method for shear wave velocity determination.

Hope that answers your question.

[groszni awesome]

  On 5/11/2017 at 3:17 AM, UmarMakhzumi said:

Hello Hanii,

The simplest soil test the can be  done is Standard Penetration Test (SPT). Published academic co-relations can be used to determine shear wave velocities and shear modulus of different soil layers against SPT N values. UET Taxila is able to do SPT test.

The preferred method to get shear wave velocity and shear modulus would be Cone Penetration Test. Its the most preffered field testing method for shear wave velocity determination.

Hope that answers your question.

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so is it possible to just using SPT to determine the soil site classification on earthquake provision? as u said that we could do some calculation empirical formula to convert the SPT to Vs maybe?

[UmarMakhzumi]

  On 5/22/2017 at 2:52 AM, groszni awesome said:

so is it possible to just using SPT to determine the soil site classification on earthquake provision? as u said that we could do some calculation empirical formula to convert the SPT to Vs maybe?

Expand  

That is correct. Just ask your geotechnical engineer to do that for your. UBC 1636.2 defines soil profile type based on shear wave velocities. For types SC and SD, you can directly use average field standard penetration resistance as defined in 1636.2.2.

For shear wave velocity (the question by OP), I am dead sure that SPT correlation can be used. Here is the history why: I was recently involved in assessment of several centrifugal stiff shaft pumps. In order to calculate the dynamic response of foundation, dynamic soil properties like shear wave velocity, dynamic modulus are required. The pumps were pretty old. While looking at the geotechnical reports for the pump foundation,  I noticed that the geotechnical engineer had used SPT N correlations to do calculate soil shear wave velocity. So I know, they can use that. So ask your geotechnical guy to furnish you that info.

Thanks.