Update mats1 card (#848)

* Add card format to MATS1 class description

* LIMIT1 and LIMIT2 can be real or blank, update MATS1 class to reflect this.

* Add STRMEAS field to MATS1 class

* Add STRMEAS field to MATS1 class.

* Add STRMEAS field to MATS1 class

* implement backwards compatibility

Author: benvb-97

pyNastran/bdf/bdf_interface/add_card.py

@@ -3805,10 +3805,10 @@ def add_mathp(self, mid: int,
         return mat
 
     def add_mats1(self, mid: int, nl_type: str,
-                  h, hr, yf, limit1, limit2,
+                  h, hr, yf, limit1, limit2, strmeas: str | None = None,
                   tid: int=0, comment: str='') -> MATS1:
         """Creates a MATS1 card"""
-        mat = MATS1(mid, nl_type, h, hr, yf, limit1, limit2,
+        mat = MATS1(mid, nl_type, h, hr, yf, limit1, limit2, strmeas,
                     tid=tid, comment=comment)
         self._add_methods.add_material_dependence_object(mat)
         return mat

pyNastran/bdf/cards/material_deps.py

@@ -22,7 +22,7 @@
 from pyNastran.bdf.cards.base_card import BaseCard
 from pyNastran.bdf.bdf_interface.internal_get import material_id, table_id
 from pyNastran.bdf.bdf_interface.assign_type import (
-    integer, integer_or_blank, double, double_or_blank, string)
+    integer, integer_or_blank, double, double_or_blank, string, string_or_blank)
 from pyNastran.bdf.field_writer_8 import print_card_8
 from pyNastran.bdf.field_writer_16 import print_card_16
 if TYPE_CHECKING:  # pragma: no cover
@@ -87,12 +87,22 @@ class MATS1(MaterialDependence):
     entry is specified with the same MID in a nonlinear solution sequence
     (SOLs 106 and 129).
 
+    Format (NX Nastran):
+    +--------+---------+-------+-------+------+-----+-----+--------+--------+
+    |   1    |   2     |    3  |  4    |  5   |  6  |  7  |  8     |  9     |
+    +========+=========+=======+=======+======+=====+=====+========+========+
+    | MATS1  |  MID    | TID   | TYPE  |  H   | YF  | HR  | LIMIT1 | LIMIT2 |
+    +--------+---------+-------+-------+------+-----+-----+--------+--------+
+    |        | STRMEAS |       |       |      |     |     |        |        |
+    +--------+---------+-------+-------+------+-----+-----+--------+--------+
+
     """
     type = 'MATS1'
 
     def __init__(self, mid: int, nl_type: Optional[str],
                  h: float, hr: float, yf: float,
-                 limit1: float, limit2: float,
+                 limit1: Optional[float], limit2: Optional[float],
+                 strmeas: Optional[str] = None,
                  tid: int=0, comment: str=''):
         MaterialDependence.__init__(self)
         if comment:
@@ -136,6 +146,11 @@ def __init__(self, mid: int, nl_type: Optional[str],
         #: Internal friction angle, measured in degrees, for the
         #: Mohr-Coulomb and Drucker-Prager yield criteria
         self.limit2 = limit2
+
+        #: Stress/strain measure of the TABLES1 or TABLEST data referenced by the TID field.
+        #: Valid for NX Nastran SOL 401 and SOL 402 only.
+        self.strmeas = strmeas
+
         self.tid_ref = None
         self.mid_ref = None
         assert tid is not None
@@ -150,7 +165,8 @@ def _init_from_empty(cls):
         yf = None
         limit1 = None
         limit2 = None
-        return MATS1(mid, nl_type, h, hr, yf, limit1, limit2, tid=tid, comment='')
+        strmeas = None
+        return MATS1(mid, nl_type, h, hr, yf, limit1, limit2, strmeas, tid=tid, comment='')
 
     def validate(self) -> None:
         if self.nl_type not in ['NLELAST', 'PLASTIC', 'PLSTRN']:
@@ -191,15 +207,21 @@ def add_card(cls, card: BDFCard, comment: str=''):
             h = double_or_blank(card, 4, 'H')
             yf = integer_or_blank(card, 5, 'yf', default=1)
             hr = integer_or_blank(card, 6, 'hr', default=1)
-            limit1 = double(card, 7, 'limit1')
+            limit1 = double_or_blank(card, 7, 'limit1')
 
             if yf in [3, 4]:
                 limit2 = double(card, 8, 'limit2')
             else:
                 #limit2 = blank(card, 8, 'limit2')
                 limit2 = None
-        assert len(card) <= 9, f'len(MATS1 card) = {len(card):d}\ncard={card}'
-        return MATS1(mid, nl_type, h, hr, yf, limit1, limit2, tid=tid, comment=comment)
+
+        if len(card) > 9:
+            strmeas = string_or_blank(card, 9, 'strmeas')
+        else:
+            strmeas = None
+
+        assert len(card) <= 10, f'len(MATS1 card) = {len(card):d}\ncard={card}'
+        return MATS1(mid, nl_type, h, hr, yf, limit1, limit2, strmeas, tid=tid, comment=comment)
 
     @classmethod
     def add_op2_data(cls, data, comment: str=''):
@@ -214,7 +236,21 @@ def add_op2_data(cls, data, comment: str=''):
             a comment for the card
 
         """
-        (mid, tid, nl_type_int, h, yf, hr, limit1, limit2) = data
+
+        if len(data) < 9:
+            (mid, tid, nl_type_int, h, yf, hr, limit1, limit2) = data
+            strmeas = None
+        else:
+            (mid, tid, nl_type_int, h, yf, hr, limit1, limit2, strmeas_int) = data
+            strmeas_map = {
+                0: None,  # NULL
+                1: 'UNDEF',
+                2: 'ENG',
+                3: 'TRUE',
+                4: 'CAUCHY',
+            }
+            strmeas = strmeas_map[strmeas_int]
+
         if nl_type_int == 1:
             nl_type = 'NLELAST'
         elif nl_type_int == 2:
@@ -224,7 +260,8 @@ def add_op2_data(cls, data, comment: str=''):
         else:  # pragma: no cover
             raise RuntimeError(f'Invalid Type:  mid={mid}; Type={nl_type_int}; must be 1=NLELAST, '
                                '2=PLASTIC, or 3=PLSTRN')
-        return MATS1(mid, nl_type, h, hr, yf, limit1, limit2, tid=tid, comment=comment)
+
+        return MATS1(mid, nl_type, h, hr, yf, limit1, limit2, strmeas, tid=tid, comment=comment)
 
     def Yf(self) -> str:
         d = {1: 'VonMises', 2: 'Tresca', 3: 'MohrCoulomb', 4: 'Drucker-Prager'}
@@ -298,7 +335,7 @@ def Tid(self) -> int:
 
     def raw_fields(self) -> list:
         list_fields = ['MATS1', self.Mid(), self.Tid(), self.nl_type,
-                       self.h, self.yf, self.hr, self.limit1, self.limit2]
+                       self.h, self.yf, self.hr, self.limit1, self.limit2, self.strmeas]
         return list_fields
 
     def repr_fields(self) -> list:

pyNastran/bdf/cards/test/test_materials.py

@@ -587,24 +587,30 @@ def test_mat3d(self):
     def test_mats1(self):
         """tests MATS1"""
         log = get_logger(level='warning')
-        model = BDF(log=log)
+
+        # MAT1 card properties
         mid = 10
         E = 3.0e7
         G = None
         nu = 0.3
-        model.add_mat1(mid, E, G, nu)
 
+        # MATS1 card properties
         tid = 0
         nl_type = 'NLELAST'
         h = None
         hr = None
         yf = None
         limit1 = None
         limit2 = None
-        unused_mats1 = model.add_mats1(
-            mid, nl_type, h, hr, yf, limit1, limit2,
-            tid=tid, comment='mats1')
-        save_load_deck(model, xref='standard', punch=True, run_remove_unused=False)
+
+        # Test model with and without STRMEAS entry
+        for strmeas in ('ENG', None):
+            model = BDF(log=log)
+            model.add_mat1(mid, E, G, nu)
+            model.add_mats1(mid, nl_type, h, hr, yf, limit1, limit2, strmeas, tid=tid, comment='mats1')
+            deck = save_load_deck(model, xref='standard', punch=True, run_remove_unused=False)
+
+            self.assertEqual(strmeas, deck.MATS1[mid].strmeas)
 
     def test_matdmg(self):
         """tests MATDMG"""

pyNastran/op2/tables/geom/mpt.py

@@ -837,17 +837,32 @@ def read_mats1(self, data: bytes, n: int) -> int:
         MATS1(503,5,90) - record 12
         """
         op2: OP2Geom = self.op2
-        ntotal = 44 * self.factor  # 11*4
-        s = Struct(mapfmt(op2._endian + b'3ifiiff3i', self.size))
+
+        ntotal = 48 * self.factor  # 12*4
+        if (len(data) - n) % ntotal != 0:  # MATS1 card format has no STRMEAS entry, reduce ntotal
+            use_strmeas = False
+            ntotal = 44 * self.factor  # 11 * 4
+            s = Struct(mapfmt(op2._endian + b'3ifiiff3i', self.size))
+        else:
+            use_strmeas = True
+            s = Struct(mapfmt(op2._endian + b'3ifiiff4i', self.size))
+
         nmaterials = (len(data) - n) // ntotal
         for unused_i in range(nmaterials):
             edata = data[n:n+ntotal]
             out = s.unpack(edata)
-            (mid, tid, Type, h, yf, hr, limit1, limit2, a, bmat, c) = out
+
+            if use_strmeas:
+                (mid, tid, Type, h, yf, hr, limit1, limit2, strmeas, a, bmat, c) = out
+                data_in = [mid, tid, Type, h, yf, hr, limit1, limit2, strmeas]
+            else:
+                (mid, tid, Type, h, yf, hr, limit1, limit2, a, bmat, c) = out
+                data_in = [mid, tid, Type, h, yf, hr, limit1, limit2]
+
             assert a == 0, a
             assert bmat == 0, bmat
             assert c == 0, c
-            data_in = [mid, tid, Type, h, yf, hr, limit1, limit2]
+
             if op2.is_debug_file:
                 op2.binary_debug.write('  MATS1=%s\n' % str(out))
             mat = MATS1.add_op2_data(data_in)

pyNastran/op2/writer/mpt_writer.py

@@ -468,9 +468,24 @@ def write_mat11(model: BDF, name: str, mids: list[int], nmaterials: int,
 def write_mats1(model: BDF, name, mids, nmaterials,
                 op2_file, op2_ascii, endian):
     """writes the MATS1"""
+
+    # check if strmeas entry should be written
+    # strategy: check random MATS1 card. if STRMEAS field is blank, do not write it for backwards compatibility
+    test_mat = model.MATS1[mids[0]]
+    write_strmeas = False if test_mat.strmeas is None else True
+
+    strmeas_map = {
+        None : 0,  # NULL
+        'UNDEF' : 1,
+        'ENG' : 2,
+        'TRUE': 3,
+        'CAUCHY': 4,
+    }
+
     key = (503, 5, 90)
-    nfields = 11
-    spack = Struct(endian + b'3ifiiff3i')
+    nfields = 12 if write_strmeas else 11
+    spack = Struct(endian + b'3ifiiff4i') if write_strmeas else Struct(endian + b'3ifiiff3i')
+
     nbytes = write_header(name, nfields, nmaterials, key, op2_file, op2_ascii)
     for mid in sorted(mids):
         mat = model.MATS1[mid]
@@ -488,16 +503,33 @@ def write_mats1(model: BDF, name, mids, nmaterials,
         else:  # pragma: no cover
             raise RuntimeError(f'Invalid Type:  Type={mat.nl_type}; must be 1=NLELAST '
                                '2=PLASTIC or 3=PLSTRN')
-        data = [mid,
-                # not sure
-                mat.tid,
-                nl_type_int,
-                0.0 if mat.h is None else mat.h,
-                0 if mat.yf is None else mat.yf,
-                0 if mat.hr is None else mat.hr,
-                0.0 if mat.limit1 is None else mat.limit1,
-                0.0 if mat.limit2 is None else mat.limit2,
-                a, bmat, c]
+
+        if write_strmeas:
+            data = [mid,
+                    # not sure
+                    mat.tid,
+                    nl_type_int,
+                    0.0 if mat.h is None else mat.h,
+                    0 if mat.yf is None else mat.yf,
+                    0 if mat.hr is None else mat.hr,
+                    0.0 if mat.limit1 is None else mat.limit1,
+                    0.0 if mat.limit2 is None else mat.limit2,
+                    strmeas_map[mat.strmeas],
+
+                    a, bmat, c]
+        else:
+            data = [mid,
+                    # not sure
+                    mat.tid,
+                    nl_type_int,
+                    0.0 if mat.h is None else mat.h,
+                    0 if mat.yf is None else mat.yf,
+                    0 if mat.hr is None else mat.hr,
+                    0.0 if mat.limit1 is None else mat.limit1,
+                    0.0 if mat.limit2 is None else mat.limit2,
+
+                    a, bmat, c]
+
         assert None not in data, f'MATS1 {data}'
         assert len(data) == nfields
         op2_ascii.write('  mid=%s data=%s\n' % (mid, data[1:]))