Struct DruckerPragerModel 

pub struct DruckerPragerModel {
    pub friction_angle: f64,
    pub cohesion: f64,
    pub shear_modulus: f64,
    pub bulk_modulus: f64,
}

Drucker-Prager yield surface for geomaterials (soil, rock, concrete).

Yield function: F = √J₂ + α·I₁ - k = 0

where: α = 2 sin φ / (√3 (3 - sin φ)) (outer cone, Mohr-Coulomb match in compression) k = 6 c cos φ / (√3 (3 - sin φ)) I₁ = tr(σ), J₂ = ½ dev:dev

Fields

friction_angle: f64

Internal friction angle φ (radians).

cohesion: f64

Cohesion c (Pa).

shear_modulus: f64

Shear modulus G (Pa).

bulk_modulus: f64

Bulk modulus K (Pa).

Implementations

impl DruckerPragerModel

pub fn new( friction_angle: f64, cohesion: f64, shear_modulus: f64, bulk_modulus: f64, ) -> Self

Create a Drucker-Prager model.

pub fn from_mohr_coulomb_degrees( phi_deg: f64, cohesion: f64, E: f64, nu: f64, ) -> Self

Create from φ (degrees), c (Pa), Young’s modulus (Pa), Poisson’s ratio.

pub fn alpha_dp(&self) -> f64

DP α parameter (friction / pressure coupling).

pub fn k_dp(&self) -> f64

DP k parameter (cohesion term).

pub fn yield_function(&self, stress: &[f64; 6]) -> f64

Yield function value F. F > 0 indicates yielding.

pub fn is_elastic(&self, stress: &[f64; 6]) -> bool

Check if stress state is elastic (F ≤ 0).

pub fn uniaxial_tensile_strength(&self) -> f64

Uniaxial tensile strength (from cohesion and friction angle).

σ_t = 2c cos φ / (1 + sin φ)

pub fn uniaxial_compressive_strength(&self) -> f64

Uniaxial compressive strength.

σ_c = 2c cos φ / (1 - sin φ)

Trait Implementations

impl Clone for DruckerPragerModel

fn clone(&self) -> DruckerPragerModel

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DruckerPragerModel

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for DruckerPragerModel