Large Deformation Hyperelastic Material Model Commands

Compressible Neo-Hookean Material Commands

nDMaterial NeoHookean3D matTag? K? G? <rho?> 

or

nDMaterial NeoHookeanCompressible3D matTag? K? G? <rho?> 

This model is the traditional compressible Neo-Hookean material model. A compressible Neo-Hookean material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter K defines the material reference bulk modulus. The parameter G defines the material reference shear modulus. The optional parameter rho defines the material reference density, the default value of rho is zero.

Although this is named compressible Neo-Hookean material, it can also be used for near-compressible or incompressible material. In this case, make K a value far bigger than G.

Decoupled Neo-Hookean Material Commands

nDMaterial DecoupledNH3D matTag? K? G? <rho?> 

or

nDMaterial DecoupledNeoHookean3D matTag? K? G? <rho?> 

This model is a decoupled model for its volumetric and isochoric parts. A decoupled Neo-Hookean material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter K defines the material reference bulk modulus. The parameter G defines the material reference shear modulus. The optional parameter rho defines the material reference density, the default value of rho is zero.

Decoupled Logarithmic Material Commands

nDMaterial DecoupledLog3D matTag? K? G? <rho?> 

or

nDMaterial DecoupledLogarithmic3D matTag? K? G? <rho?> 

This model is a decoupled model for its volumetric and isochoric parts. A decoupled logarithmic material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter K defines the material reference bulk modulus. The parameter G defines the material reference shear modulus. The optional parameter rho defines the material reference density, the default value of rho is zero.

Decoupled Mooney-Rivlin-Simo Material Commands

nDMaterial DecoupledMRS3D matTag? c1? c2? K? <rho?> 

or

nDMaterial DecoupledMooneyRivlinSimo3D matTag? c1? c2? K? <rho?> 

This model is a decoupled model for its volumetric and isochoric parts. Its isochoric part is Mooney-Rivlin model and its volumetric part is Simo-Pister model. A decoupled Mooney-Rivlin-Simo material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter c1 and c2 define the material constants. The parameter K defines the material reference bulk modulus. The optional parameter rho defines the material reference density, the default value of rho is zero.

Decoupled Ogden-Simo Material Commands

nDMaterial DecoupledOS3D matTag? N? c1? ... cN? m1? ... mN? K? <rho?> 

or

nDMaterial DecoupledOgdenSimo3D matTag? N? c1? ... cN? m1? ... mN? K? <rho?> 

This model is a decoupled model for its volumetric and isochoric parts. Its isochoric part is Ogden model and its volumetric part is Simo-Pister model. A decoupled Ogden-Simo material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter N, c1, ..., cN, and m1, ..., mN define the material constants. The parameter K defines the material reference bulk modulus. The optional parameter rho defines the material reference density, the default value of rho is zero.

Decoupled Mooney-Rivlin Material Commands

nDMaterial DecoupledMR3D matTag? c1? c2? <rho?> 

or

nDMaterial DecoupledMooneyRivlin3D matTag? c1? c2? <rho?> 

This model is a decoupled isochoric model. A decoupled Mooney-Rivlin-Simo material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter c1 and c2 define the material constants. The optional parameter rho defines the material reference density, the default value of rho is zero.

Decoupled Ogden Material Commands

nDMaterial DecoupledOgden3D matTag? N? c1? ... cN? m1? ... mN? <rho?> 

This model is a decoupled isochoric model. A decoupled Ogden-Simo material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter N, c1, ..., cN, and m1, ..., mN define the material constants. The optional parameter rho defines the material reference density, the default value of rho is zero.

Decoupled Simo-Pister Material Commands

nDMaterial DecoupledSP3D matTag? K? <rho?> 

or

nDMaterial DecoupledSimoPister3D matTag? K? <rho?> 

This model is a decoupled volumetric model. A decoupled Simo-Pister material is constructed using nDMaterial command. The argument matTag is used to uniquely identify this nDMaterial object among nDMaterial objects in the BasicBuilder object. The parameter K defines the material reference bulk modulus. The optional parameter rho defines the material reference density, the default value of rho is zero.