nonlinear spring input file abaqus

Hello all,

I am currently working at a structural dynamic problem with Abaqus/Explicit. The work involves an impact and in this context the goal is to connect two rigid bodies (with their constraint, mass and velocity field) to each other with a NONLINEAR SPRING; the element used is the so called SPRINGA element.

Using File-->Import-->Model I have imported the input file, which I have previously modified in the following way:

*Spring, elset=SPRING-spring, nonlinear

0,0

1000,0.002481