What is G (equivalent) in QUAKE/W module?

On giving a constant Gmax as an input parameter, there is a range of values that could be observed for G (equivalent). What exactly is this G (equivalent) ?


  • Hi!

    Thank you so much for your post

    G equivalent, in the equivalent linear model, is a value that changes in every iteration by a function and uses as parameter Gmax.

    The Equivalent Linear model is very similar to the linear-elastic model. The difference is that the soil stiffness G is modified in response to computed strains. 

    With the Equivalent Linear model QUAKE/W starts a dynamic analysis with the specified soil stiffness. QUAKE/W steps through the entire earthquake record and identifies the peak shear strains at each Gauss numerical integration point in each element. The shear modulus is then modified according a specified G reduction function and the process is repeated. This iterative procedure continues until the required G modifications are within a specified tolerance.

    If you have any more questions, please feel free to reach out!