/PROP/TYPE25 (SPR

Block Format Keyword

/PROP/TYPE25 - Axisymmetric Spring Property Set

Description

This property set is used to define the axisymmetric spring property set.

prop_type25_tension

Tension/Compression

prop_type25_y_radial

Shear (Radial)

prop_type25_torsion

Torsion

prop_type25_z_radial

Bend (Radial)

Format

(1)	(3)	(5)	(6)	(7)	(8)	(9)	(10)
/PROP/TYPE25/prop_ID/unit_ID or /PROP/SPR_AXI/prop_ID/unit_ID
prop_title
Mass	Inertia	skew_ID	sens_ID	Isflag	Ifail	Ileng	Ifail2

Tension/Compression

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(9)
K1		C1		A1		B1	D1
fct_ID11	H1	fct_ID21	fct_ID31	F1
Ascale1		E1		fct_ID41	Hscale1

Shear (Radial)

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(9)
K2		C2		A2		B2	D2
fct_ID12	H2	fct_ID22	fct_ID32	F2
Ascale2		E2		fct_ID42	Hscale2

Torsion

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(9)
K3		C3		A3		B3	D3
fct_ID13	H3	fct_ID23	fct_ID33	F3
Ascale3		E3		fct_ID43	Hscale3

Bend (Radial)

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(9)
K4		C4		A4		B4	D4
fct_ID14	H4	fct_ID24	fct_ID34	F4
Ascale4		E4		fct_ID44	Hscale4

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)

c1		n1
c2		n2
c3		n3
c4		n4

Field	Contents	SI Unit Example
prop_ID	Property identifier (Integer, maximum 10 digits)
unit_ID	Optional unit identifier (Integer, maximum 10 digits)
prop_title	Property title (Character, maximum 100 characters)
Mass	Spring mass (Real)
Inertia	Spring inertia (Real)
skew_ID	Skew system identifier (Integer)
sens_ID	Sensor identifier (Integer)
Isflag	Sensor flag (Integer) =0: See Comment 3 =1: See Comment 4
Ifail	Failure criteria (Integer) = 0: uni-directional criteria = 1: multi-directional criteria
Ileng	Input per unit length flag (Integer) = 0: See Comment 2 and Comment 7 = 1: See Comment 8
Ifail2	Failure model flag Default = 0 (Integer) = 0: old displacement criteria = 1: new displacement criteria = 2: force criteria = 3: internal energy criteria
K1	Stiffness for tension (Real)
C1	Damping for tension (Real)
A1	Coefficient for strain rate effect in tension (homogeneous to a force) Default = 1.0 (Real)
B1	Logarithmic coefficient for strain rate effect in tension (homogeneous to a force) (Real)
D1	Scale coefficients for elongation velocity Default = 1.0 (Real)
fct_ID11	Function identifier defining If H1 =4: Upper yield curve function identifier (Integer) = 0 for linear spring
H1	Hardening flag (Integer) = 0: Nonlinear elastic spring = 1: Nonlinear elastic plastic spring = 2: Nonlinear elasto-plastic spring with decoupled hardening in tension and compression = 4: Nonlinear elastic plastic spring “kinematic” hardening = 5: Nonlinear elasto-plastic spring with nonlinear unloading = 6: Nonlinear elasto-plastic spring with isotropic hardening and nonlinear unloading = 7: Nonlinear spring with elastic Hysteresis
fct_ID21	Function identifier defining (Integer)
fct_ID31	Function used only for unloading If H1=4: Function identifier defining lower yield curve If H1=5: Function identifier defining residual displacement vs maximum displacement (Integer)
fct_ID41	Function identifier defining (Integer)
Hscale1	Coefficient for (homogeneous to a force) Default = 1 (Real)
F1	Scale factor for in function (Real)
	Negative failure limit Default = -1030 (Real)
	Positive failure limit Default = 1030 (Real)
Ascale1	Abscissa scale factor for (fct_ID11 and fct_ID31) (Real)
E1	Coefficient for strain rate in tension (homogeneous to a force) (Real)
K3	Stiffness for torsion (Real)
C3	Damping for torsion (Real)
A3	Coefficient for strain rate effect in torsion (homogeneous to a moment) Default = 1.0 (Real)
B3	Logarithmic coefficient for strain rate effect in torsion (homogeneous to a moment) (Real)
D3	Scale coefficients for torsion velocity Default = 1.0 (Real)
fct_ID13	Function identifier defining If H3=4: Function identifier defining upper yield curve (Integer) = 0: linear spring
H3	Hardening flag (Integer) = 0: Nonlinear elastic spring = 1: Nonlinear elastic plastic spring = 2: Nonlinear elasto-plastic spring with decoupled hardening in tension and compression = 4: Nonlinear elastic plastic spring “kinematic” hardening = 5: Nonlinear elasto-plastic spring with nonlinear unloading = 6: Nonlinear elasto-plastic spring with isotropic hardening and nonlinear unloading = 7: Nonlinear spring with elastic Hysteresis
fct_ID23	Function identifier defining (Integer)
fct_ID33	Function used only for unloading If H3=4: Function identifier defining lower yield curve If H3=5: Function identifier defining residual displacement vs maximum displacement (Integer)
fct_ID43	Function identifier defining (Integer)
Hscale3	Coefficient for (homogeneous to a force) Default = 1 (Real)
F3	Scale factor for in function (Real)
	Negative failure limit Default = -1030 (Real)
	Positive failure limit Default = 1030 (Real)
Ascale3	Abscissa scale factor for (fct_ID13 and fct_ID33) (Real)
E3	Coefficient for strain rate effects in torsion (homogeneous to a moment) (Real)
K2	Stiffness for shear (Real)
C2	Damping for shear (Real)
A2	Coefficient for strain rate effect in shear (homogeneous to a force) Default = 1.0 (Real)
B2	Logarithmic coefficient for strain rate effect in shear (homogeneous to a force) Default = 1.0 (Real)
D2	Scale coefficients for shear velocity Default = 1.0 (Real)
fct_ID12	Function identifier defining If H2=4: Function identifier defining upper yield curve (Integer) = 0: linear spring
H2	Hardening flag (Integer) = 0: Nonlinear elastic spring = 1: Nonlinear elastic plastic spring = 2: Nonlinear elasto-plastic spring with decoupled hardening in tension and compression = 4: Nonlinear elastic plastic spring “kinematic” hardening = 5: Nonlinear elasto-plastic spring with nonlinear unloading = 6: Nonlinear elasto-plastic spring with isotropic hardening and nonlinear unloading = 7: Nonlinear spring with elastic Hysteresis
fct_ID22	Function identifier defining (Integer)
fct_ID32	Function used only for unloading If H2=4: Function identifier defining lower yield curve If H2=5: Function identifier defining residual displacement vs maximum displacement (Integer)
fct_ID42	Function identifier defining (Integer)
Hscale2	Coefficient for (homogeneous to a force) Default = 1 (Real)
F2	Scale factor for in function (Real)
	Negative failure limit Default = -1030 (Real)
	Positive failure limit Default = 1030 (Real)
E2	Coefficient for strain rate effect in shear (homogeneous to a force) (Real)
Ascale2	Abscissa scale factor for (fct_ID12 and fct_ID32) (Real)
K4	Stiffness for bending (Real)
C4	Damping for bending (Real)
A4	Coefficient for strain rate effect in bending (homogeneous to a moment) Default = 1.0 (Real)
B4	Logarithmic coefficient for strain rate effect in bending (homogeneous to a moment) Default = 1.0 (Real)
D4	Scale coefficients for bending velocity Default = 1.0 (Real)
fct_ID14	Function identifier defining If H4=4: Function identifier defining upper yield curve (Integer) = 0: linear spring
H4	Hardening flag (Integer) = 0: Nonlinear elastic spring = 1: Nonlinear elastic plastic spring = 2: Nonlinear elasto-plastic spring with decoupled hardening in tension and compression = 4: Nonlinear elastic plastic spring “kinematic” hardening = 5: Nonlinear elasto-plastic spring with nonlinear unloading = 6: Nonlinear elasto-plastic spring with isotropic hardening and nonlinear unloading = 7: Nonlinear spring with elastic Hysteresis
fct_ID24	Function identifier defining (Integer)
fct_ID34	Function used only for unloading If H4=4: Function identifier defining lower yield curve If H4=5: Function identifier defining residual displacement vs maximum displacement (Integer)
fct_ID44	Function identifier defining (Integer)
Hscale4	Coefficient for (homogeneous to a force) Default = 1 (Real)
F4	Scale factor for in function (Real)
	Negative failure limit Default = -1030 (Real)
	Positive failure limit Default = 1030 (Real)
Ascale4	Abscissa scale factor for (fct_ID14 and fct_ID34) (Real)
E4	Coefficient for strain rate effect in bending (homogeneous to a force) (Real)
	Reference translational velocity Default = 1.0 (Real)
	Reference rotational velocity Default = 1.0 (Real)
c1	Relative velocity coefficient in translation X Default = 0.0 (Real)
n1	Relative velocity exponent in translation X Default = 0.0 (Real)
	“Mult” factor in translation X Default = 1.0 (Real)
	Exponent in translation X Default = 2.0 (Real)
c2	Relative velocity coefficient in shear Default = 0.0 (Real)
n2	Relative velocity exponent in shear Default = 0.0 (Real)
	“Mult” factor in shear Default = 1.0 (Real)
	Exponent in shear Default = 2.0 (Real)
c3	Relative velocity coefficient in torsion X Default = 0.0 (Real)
n3	Relative velocity exponent in torsion X Default = 0.0 (Real)
	“Mult” factor in torsion X Default = 1.0 (Real)
	Exponent in torsion X Default = 2.0 (Real)
c4	Relative velocity coefficient in bending Default = 0.0 (Real)
n4	Relative velocity exponent in bending Default = 0.0 (Real)
	“Mult” factor in bending Default = 1.0 (Real)
	Exponent in bending Default = 2.0 (Real)

1.	The spring’s X direction is defined using nodes N1 and N2 of the spring.

If the node of the spring N3 is defined, the spring’s Y’ direction is defined using nodes N1 and N3 of the spring. N3, N2, and N1 should not be in a line.

•	The Z direction is:

•	If node N3 is not defined in the element input, and skew system is defined in the property input, the Z direction is:

•	If neither node N3 nor skew system are defined in input, the Z direction is:

prop_spr_beam14

Finally, Y direction is found as:

2.	In case of Ileng =0, the force in the spring is computed as:

Linear spring:

with i=1, 2

with i= 3, 4

Nonlinear spring:

with i= 1, 2

with i= 3, 4

with

Note:

•	Here, (with ) is the difference between the current length and the initial length of the spring element for corresponding translational DOF.

•	is the relative angle for corresponding rotational DOF in radians.

•	For linear springs, , and , , and are null functions and Ai, Bi, Ei, and Hscalei are not taken into account.

•	If stiffness function (or ) is requested, then K is used as a slope for unloading only.

•	If K is lower than the maximum slope of function (or ) (K is not consistent with the maximum slope of the curve), K is set to the maximum slope of the curve.

linear_spring

Linear spring

nonlinear_spring_0

Nonlinear elastic spring, Hi=0

nonlinear_spring_1

Nonlinear elastic plastic spring, Hi=1

nonlinear_spring_2

Nonlinear elasto-plastic spring with decoupling hardening in tension and compression, Hi=2

nonlinear_spring_4

Nonlinear elastic plastic spring 'kinematic' hardening, Hi=4

nonlinear_spring_5

Nonlinear elasto-plastic spring with nonlinear unloading, Hi=5

nonlinear_spring_6

Nonlinear elasto-plastic spring with isotropic hardening and nonlinear unloading, Hi=6

nonlinear_spring_7

Nonlinear spring with elastic Hystersis, Hi=7

3.	If Ileng = 1, all input are per unit length:

•	Spring mass = Spring stiffness = Spring damping = Spring inertia =

Where, is the reference spring length.

•	The force in the spring is computed as:

- Linear spring:

with i=1, 2

with i=3, 4

- Nonlinear spring:

with i=1, 2

with i=3, 4

where, is the engineering strain and defined as:

- Force functions are given versus engineering strain and engineering strain rate.

- Failure criteria are defined with respect to strain. Input negative/positive failure limit should be related to initial length

4.	If hardening flag is 4, hardening is kinematic. Lower and upper yield curves are the same.

5.	If hardening flag is 5, residual deformation is a function of maximum displacement:

with i=1,2

with i=3,4

6.	The decoupled hardening (hardening flag Hi=2) and kinematic hardening (hardening flag Hi=4) models are only valid in axial direction (tension and torsion). They are not available in radial direction (shear and bending).

7.	Failure criteria:

•	If the failure criteria are uni-directional Ifail=0, the spring fails as soon as one of the criteria is met in one direction:

or , with and being the failure limits in direction i=1, 2

or , with and being the failure limits in direction i=3, 4

For each direction (or ) should be negative and (or ) should be positive. If the values are zero, then no failure will be taken into account.

•	If the failure criteria is multi-directional Ifail=1, the spring fails when the following criteria is fulfilled:

For “old” displacement formulation (Ifail =0), the coefficients i and i are equal to 1.0 and 2.0, respectively.

New formulation ( Ifail2 > 0) allows to model velocity dependent failure limit for translational DOF:

Where, or is the static failure limit in translational directions (Lines 5 and 8), and v0 is the reference velocity.

•	Force and energy criteria are activated with Ifail2=2 or 3:

In this case the displacement values are replaced by positive failure force or failure energy values.

New formulation (Ifail2 =1) allows you to model velocity dependent failure limit for rotational DOF:

Where, or is the static failure limit in rotational direction (Lines 11 and 14), and is the reference velocity.

Moment and energy criteria are activated with Ifail2=2 or 3:

In this case the rotation values are replaced by positive failure moment or failure energy values.

8.	Spring activated and/or deactivated by sensor:

•	If sens_ID ≠ 0 and Isflag = 0, the spring element is activated by the sens_ID.

•	If sens_ID ≠ 0 and Isflag = 1, the spring element is deactivated by the sens_ID.

•	Spring elements with sensor activation or deactivation are mainly used for the pretension model.

•	If a sensor is used for activating or deactivating a spring, the reference length of the spring at sensor activation (or deactivation) is equal to the nodal distance at time =0.

/PROP/TYPE25 (SPR_AXI)

/PROP/TYPE25 (SPR_AXI)

/PROP/TYPE25 (SPR_AXI)