*DYNIMP

Data format:

A single line with 5 parameters, as follows:

ITEMAX DELTA ALPHA IOPTDT ITMIN

Status:

Optional.

Purpose:

To set control parameters of the Newmark implicit time-domain integration scheme.

Details :

Parameter	Description
DTREC	Maximum number of iterations at each time step Default value is 30
DELTA	Newmark's delta (or gamma) coefficient. Default value is 0.5
ALPHA	Newmark's alpha (or beta) coefficient. Default value is 0.25
IOPDT	Sets whether or not the variable time-step is to be used. IOPTD = 0 no optimisation of the time step length IOPTD == 1 optimisation of the time step. Default value is 0
ITMIN	If the program converges five consecutive time steps in less than ITMIN iterations, the time step will be increased. default value is 1

Example:

*DYNIMP
30 .5 .25 0 1

This example uses the default values. It would be therefore unnecessary to write this keyword in the data file for this specific case.