Shear Modulus G

[ONENGINEER]

What is the use of the curves for G/Gmail against the shear rate? Thanks

 

[EireChch]

Which curves? Can you post a reference

 

[fattdad]

shear modulus is not linear. Low strain modulus and high strain shear modulus differ. The graphs show that difference.

f-d

ípapß gordo ainÆt no madre flaca!

 

[EireChch]

Do you mean G/Gmax (just tried to autocorrect it to mail for me so I take it you are!)

f-d is right.

That graph shows that the more strain you have the less stiffness you get.

Retaining walls are typically small strain problems and they benefit from using small strain stiffness. For example in plaxis you can use the hardening small strain model (HS small). You select the strain rate, for example 0.001. As your strain increases it uses your shear modulus (0.7 x Gmax) to a strain of 0.001 to determine deflections. After that it uses your standards Young’s modulus to determine deflections.

 

[Okiryu]

Look at Google for "Modulus of reduction curves". These curves are used in geotechnical earthquake engineering - site response analysis.

Also, agree with f-d and EireChch...

What will be the application?

 

[ONENGINEER]

Thank you all for your replies and my apology for mis-autocorrection. G/Gmax against shear rate was intended as you guessed correctly. There are usually two curves and wonder if this is a range or two different cases.

I am familiarizing myself with soil dynamics with no special application.