liquefaction.k_sigma()

Overburden correction factor on the cyclic resistance ratio.

Usage

Source

liquefaction.k_sigma(
    n160cs,
    sigma_v0,
    pa=P_ATM,
)

Parameters

n160cs: array_like

Clean-sand equivalent blow count, clamped to 37.

sigma_v0: array_like

Vertical effective stress, ksf.

pa: float = P_ATM

Atmospheric pressure, ksf.

Returns

ndarray

min(1 - C ln(sigma'v0 / pa), 1.1) with C = min(1 / (18.9 - 2.55 sqrt(N)), 0.3).

References

Boulanger and Idriss (2014), Eqs. 2.16 and 2.16b.