PISM, A Parallel Ice Sheet Model  stable v2.0.4 committed by Constantine Khrulev on 2022-05-25 12:02:27 -0800
MohrCoulombPointwise.cc
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19 #include <cmath> // pow, tan, atan
20 
21 #include "MohrCoulombPointwise.hh"
22 
23 namespace pism {
24 
26  m_W_till_max = config->get_number("hydrology.tillwat_max");
27  m_till_cohesion = config->get_number("basal_yield_stress.mohr_coulomb.till_cohesion");
28  m_reference_effective_pressure = config->get_number("basal_yield_stress.mohr_coulomb.till_reference_effective_pressure");
29  m_reference_void_ratio = config->get_number("basal_yield_stress.mohr_coulomb.till_reference_void_ratio");
30  m_compressibility_coefficient = config->get_number("basal_yield_stress.mohr_coulomb.till_compressibility_coefficient");
31 }
32 
34  double P_overburden,
35  double water_thickness) const {
36 
37  double
38  s = water_thickness / m_W_till_max,
40  N_till = (N0 * pow(delta * P_overburden / N0, s) *
41  pow(10.0, (m_reference_void_ratio / m_compressibility_coefficient) * (1.0 - s)));
42 
43  return std::min(P_overburden, N_till);
44 }
45 
47  double P_overburden,
48  double water_thickness,
49  double phi) const {
50 
51  double N_till = effective_pressure(delta, P_overburden, water_thickness);
52 
53  return m_till_cohesion + N_till * tan((M_PI / 180.0) * phi);
54 }
55 
57  double P_overburden,
58  double water_thickness,
59  double yield_stress) const {
60 
61  double N_till = effective_pressure(delta, P_overburden, water_thickness);
62 
63  return 180.0 / M_PI * atan((yield_stress - m_till_cohesion) / N_till);
64 
65 }
66 
67 } // end of namespace pism
std::shared_ptr< const Config > ConstPtr
double yield_stress(double delta, double P_overburden, double water_thickness, double phi) const
MohrCoulombPointwise(Config::ConstPtr config)
double m_W_till_max
Maximum till water thickness.
double till_friction_angle(double delta, double P_overburden, double water_thickness, double yield_stress) const
double m_till_cohesion
Cohesion of till.
double m_compressibility_coefficient
Coefficient of compressibility of till.
double effective_pressure(double delta, double P_overburden, double water_thickness) const
double m_reference_void_ratio
Reference void ratio.
double m_reference_effective_pressure
Reference effective pressure.
const double phi
Definition: exactTestK.c:41
double min(const IceModelVec2S &input)
Finds minimum over all the values in an IceModelVec2S object. Ignores ghosts.