## *CONTACT PRINT

Keyword type: step

This option is used to print selected nodal and/or integration point and/or surface variables in file jobname.dat. The following variables can be selected:

• Relative contact displacements (key=CDIS)
• Contact stresses (key=CSTR)
• Contact spring energy (key=CELS)
• Total number of contact elements (key=CNUM)
• Total force on a slave surface (key=CF)
• Total normal force on a slave surface (key=CFN)
• Total shear force on a slave surface (key=CFS)

Contact quantities CDIS, CSTR and CELS are stored for all active slave nodes in the model for node-to-face penalty contact and for all active integration points in the slave face for face-to-face penalty contact. The relative contact displacements and the stresses consist of one component normal to the master surface and two components tangential to it. Positive values of the normal components represent the normal material overlap and the pressure, respectively. For the direction of the tangential unit vectors used to calculate the relative tangential displacement and shear stresses the user is referred to *CONTACT FILE. The energy is a scalar quantity.

The contact quantity CNUM is one scalar listing the total number of contact elements in the model.

The quantities CF, CFN and CFS represent the total force, total normal force and total shear force acting on the slave surface, respectively, for a selected face-to-face penalty contact pair. In addition, moments of these forces about the global origin, the location of the center of gravity and the area of the contact area and the moment about the center of gravity are printed.

There are five parameters, FREQUENCY, TIME POINTS, TOTALS, SLAVE and MASTER. FREQUENCY and TIME POINTS are mutually exclusive.

The parameter FREQUENCY is optional, and applies to nonlinear calculations where a step can consist of several increments. Default is FREQUENCY=1, which indicates that the results of all increments will be stored. FREQUENCY=N with N an integer indicates that the results of every Nth increment will be stored. The final results of a step are always stored. If you only want the final results, choose N very big. The value of N applies to *OUTPUT,*ELEMENT OUTPUT, *EL FILE, *ELPRINT, *NODE OUTPUT, *NODE FILE, *NODE PRINT, *SECTION PRINT,*CONTACT OUTPUT, *CONTACT FILE and *CONTACT PRINT. If the FREQUENCY parameter is used for more than one of these keywords with conflicting values of N, the last value applies to all. A frequency parameter stays active across several steps until it is overwritten by another FREQUENCY value or the TIME POINTS parameter.

With the parameter TIME POINTS a time point sequence can be referenced, defined by a *TIME POINTS keyword. In that case, output will be provided for all time points of the sequence within the step and additionally at the end of the step. No other output will be stored and the FREQUENCY parameter is not taken into account. Within a step only one time point sequence can be active. If more than one is specified, the last one defined on any of the keyword cards *NODE FILE, *EL FILE, *NODE PRINT, *EL PRINT or *FACE PRINT will be active. The TIME POINTS option should not be used together with the DIRECT option on the procedure card. The TIME POINTS parameters stays active across several steps until it is replaced by another TIME POINTS value or the FREQUENCY parameter.

The first occurrence of a *CONTACT PRINT keyword card within a step wipes out all previous contact variable selections for print output. If no *CONTACT PRINT card is used within a step the selections of the previous step apply, if any.

The parameter TOTALS only applies to the energy. If TOTALS=YES the sum of the contact spring energy for all contact definitions is printed in addition to their value for each active slave node (node-to-face contact) or active slave face integration point (face-to-face penalty contact) separately. If TOTALS=ONLY is selected the sum is printed but the individual contributions are not. If TOTALS=NO (default) the individual contributions are printed, but their sum is not.

If the model contains axisymmetric elements the spring energy applies to a segment of . So for the total spring energy this value has to be multiplied by 180.

The parameters SLAVE and MASTER are used to define a contact pair. They are only needed for the output variables CF, CFN and CFS. They have to correspond to the face based master of slave surface of an existing contact pair.

First line:

• *CONTACT PRINT
Second line:
• Identifying keys for the variables to be printed, separated by commas.

Example:

*CONTACT PRINT
CDIS


requests the storage of the relative displacements in all slave nodes in the .dat file.

Example files: beampkin, beamrb, contact5.