*SPRINGPRO

Data format:

An arbitrary number of lines with up to 20 values each ('&' character included)

IPRO NBVAL U1 EF1 ... UNBVAL EFNBVAL

Status :

Mandatory when spring or flex-joint elements are used

Purpose :

To define mechanical properties of a set of spring or flex-joint elements

Restriction :

The total number of spring and flex-joint properties sets is limited to MAXPRO (version dependent)

Details :

Parameter	Description
IPRO	identification number of the following set of properties
NBVAL	number of values defining the element stiffness K
(Ui, EFi)	Couples of values defining the spring behaviour by couple (displacement, effort (force or moment) )

Spring Flex-joint

In case of a linear spring, a single couple is defined as (displacement, stiffness)
In that case, the stiffness is assume to be symmetric versus the origin

Note

If (NBVAL == 0), a non-linear spring is defined.

Note

If (NBVAL == 0), the keyword is then:

*SPRINGPRO

IPRO 0 K_layers K_limit DeltaX_limit tplast xCp K_layers : initial stiffness before the non-linear behavior occurs;

K_limit : asymptotic stiffness;

DeltaX_limit : limit elongation defining the non-linear threshold;

tplast : first parameter for the non-linear law. Equals zero for a bi- linear hardening law;

xCp : second parameter of the non-linear law (automatically computed if tplast=0.