# Release Notes for TrueGrid^{®}

Version 3.1.2, May 1, 2015

1. The new command TRACT in the merge phase assigns traction to face sets.

TRACT FSET set_name load_curve_# amplitude xn yn zn

This is a load that will apply to models built for LS-DYNA, ANSYS, ABAQUS, and NASTRAN.

2. The abaqstep command, used to associate conditions to different analysis
steps in the simulation, has a new option to make an association of
traction to an analysis step. That option
is:

ABDSLOAD BLC load_curve_# TRACT ;

3. The LSDYNA material 72 has been replaced with 72REL3. Since LSDYNA has
dropped material 72, so has TrueGrid. If anyone is using an older version
of LSDYNA with material 72 (the obsolete material model), please let XYZ
Scientific Applications know so that we can continue supporting it.

This new version has the following parameters:

PR ratio - Constant Poission's Ratio Model

FT strength - Unixial tensile strength

A0 failure - Maximum shear failure surface parameter a0

A1 failure - Maximum shear failure surface parameter a1

A2 failure - Maximum shear failure surface parameter a2

B1 factor - Damage Scaling Factor

OMEGA dilatancy - Fractional dilatancy

A1F failue - Pressure Hardening Coefficient for Failed Material

SL factor - Lamda stretch factor, s

NOUT strain - Effective plastic strain selector

EDROP decay - Post peak dilatancy decay

RSIZE factor - Unit conversion factor for length

UCF factor - Unit conversion factor for stress

LCRATE load_curve - Load curve for strain rate effects

LOCWID length - 3 X max aggregrate diameter

NPTS #_points - Number of points in l v.s. n damage

L01 value - 1st value of damage function

L02 value - 2nd value of damage function

L03 value - 3rd value of damage function

L04 value - 4th value of damage function

L05 value - 5th value of damage function

L06 value - 6th value of damage function

L07 value - 7th value of damage function

L08 value - 8th value of damage function

Lo9 value - 9th value of damage function

L10 value - 10th value of damage function

L11 value - 11th value of damage function

L12 value - 12th value of damage function

L13 value - 13th value of damage function

B3 coefficient - Triaxial tension damage coefficient

A0Y yield - Initial yield surface coefficient A0Y

A1Y yield - Initial yield surface coefficient A1Y

N01 factor - 1st value of scale factor

N02 factor - 2nd value of scale factor

N03 factor - 3rd value of scale factor

N04 factor - 4th value of scale factor

N05 factor - 5th value of scale factor

N06 factor - 6th value of scale factor

N07 factor - 7th value of scale factor

N08 factor - 8th value of scale factor

N09 factor - 9th value of scale factor

N10 factor - 10th value of scale factor

N11 factor - 11th value of scale factor

N12 factor - 12th value of scale factor

N13 factor - 13th value of scale factor

B2 exponent - Tensile damage scaling exponent b2

A2F coefficient - Residual failure surface coefficient A2F

A2Y coefficient - Initial yeild surface coefficient A2Y

4. The output data created using the VERBATIM command for
keyword LS-DYNA has been moved in the output file. It now
appears after the material models.