I am trying to incorporate sand as py material using opensees. The pysimple1 material as listed in opensees has in it the following:
pult and y50. These apply to clay. Does anyone know what to use for sand . do we use y50 for sand as well? if so what is the equation for it?
thank you
py material
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sharidamiri
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Boulanger
Inputs for sand
For most p-y equations, if you define the point at p50-y50, you can develop the rest of the curve. Using y50 as in input parameter keeps the input parameter list consistent and forces the user to become aware of the relative y50 values for different relations. Or at least that was the logic.
For example, the API-sand curve uses the equation:
p/pult = tanh(K*y/pult)
where K is the product k*x and pult has already been factored by the parameter A. The design curves for API give the A and k. The value of p equals 50% of pult at:
p/pult = 0.5 = tanh(0.549)
which gives us,
K*y50/pult = 0.549
or
y50=0.549*pult/K
We have used spreadsheets (in MathCad or Excel) to generate input parameters, and so computing y50 for API sand is quite easy. More recently, Scott Brandenberg implemented some p-y generator commands in OpenSees that make this easier. You might want to try them out.
I hope that helps.
For example, the API-sand curve uses the equation:
p/pult = tanh(K*y/pult)
where K is the product k*x and pult has already been factored by the parameter A. The design curves for API give the A and k. The value of p equals 50% of pult at:
p/pult = 0.5 = tanh(0.549)
which gives us,
K*y50/pult = 0.549
or
y50=0.549*pult/K
We have used spreadsheets (in MathCad or Excel) to generate input parameters, and so computing y50 for API sand is quite easy. More recently, Scott Brandenberg implemented some p-y generator commands in OpenSees that make this easier. You might want to try them out.
I hope that helps.