Example Database
The following structural analysis example gives an informal overview of a typical B2000++ model database. A simple beam modeled by beam elements is loaded dynamically. The example is taken from the B2000++ example collection, see
<prefix>/share/b200pp/verification/staticstatic/scordelis_lo_roof
where <prefix> is the installation directory prefix, such as
/opt/smr or $HOME/smr.
In this example all elements are defined within the same single branch
number 1. A static deformation analysis is performed with one load
case, producing solution datasets DISP.*.
The table below contains a MemCom dataset directory of all datasets generated by B2000++.
Type File-address N-of-rows N-of-cols Name
---- ------------ --------- --------- ----
I 410264 1 0 ADIR
$ 384952 207 0 BDTB.1
$ 409896 2 118 CASE.1
F 366456 289 3 COOR.1
AT 25216 3072 1 COOR_IP.1.0.0.1
F 448304 289 6 DISP.1.0.0.1
F 440048 256 4 DISP_E.1.0.0.1
AT 99024 3072 1 DISP_IP.1.0.0.1
F 396232 134 3 EBC.1.0.0.1
I 387416 16 2 EDGELIST.1.0.0.EPATCH-1-E1
...
$ 3104 278 1307 ELEMENT-PARAMETERS
I 386320 256 1 ELEMENTLIST.1.0.0.EPATCH-1-B
AT 488 3072 2 ELEM_IP.1.0.0.1
$ 410400 313 0 EPATCH.1
ST 64 256 6 ETAB.1
I 389304 16 2 FACELIST.1.0.0.EPATCH-1-F1
...
AT 172832 3072 1 FAILURE_INDEX.1.0.0.1
AT 197488 3072 1 FC_VON_MISES.1.0.0.1
$ 487624 14 248 FIELDS
F 426112 289 6 FORC.1.0.0.1
F 417856 256 4 FORC_E.1.0.0.1
AT 0 12 2 IP.1.0.0.1
$ 396000 228 0 MATERIAL.1
AT 222144 3072 1 MBASE_IP.1.0.0.1
F 399552 256 5 NBC.1.0.0.1
I 380328 289 4 NODA.1
F 410720 289 3 NODE-NORMALS.1
$ 32 26 118 NODE-PARAMETERS
I 385160 289 1 NODELIST.1.0.0.EPATCH-1-B
...
F 470496 289 6 RCFO.1.0.0.1
F 462240 256 4 RCFO_E.1.0.0.1
$ 487192 430 0 SOLUTION.0.0.0.1
AT 443408 3072 1 STRAIN.1.0.0.1
AT 590944 3072 1 STRESS.1.0.0.1
K 0 26 0 TITLE
AT 738480 3072 1 VOLUME.1.0.0.1
The element description tables ELEMENT-PARAMETERS describe the parameters of all element types. Here, the sub-table 5 describing the Q4 used in this example element is listed:
'ELNO': array([6], dtype=int32),
'NAME': 'Q4',
'NTYPES': array([1, 1, 1, 1], dtype=int32)}
ELNO designates the internal element number, NAME the generic
element name, and NTYPES node types of each of the element nodes,
see NODE-PARAMETERS. Any element always refers to this
table, either by generic name or by internal element type number
ELNO. Note that the generic name also defines the element class.
The analysis directive table contains the basic model parameters in the data set descriptor. The set itself contains the list of all active branches (not listed). The descriptor is listed here:
Descriptor of set "ADIR"
'CASES': array([1], dtype=int32)
'DBVERSION': array([4], dtype=int32)
'DRILLS': array([1.e-08])
'SYSTEM': 'B2000++'
'VERSION': array([4, 3, 0], dtype=int32)
The branch descriptor table contains the primary information on the branch. Any branch can be reconstructed by interpreting the branch descriptor. BDTB.<br> stores parameters associated to the branch, such as the type of the mesh, the number of element etc. For our example the relational table contains, among others:
Relational table "BDTB.1"
Keyword Type Size Value(s)
------- ---- ---- -------
BTRF F 12 [0,0,0,1,0,0,0,1,0,0,0,1,]
LTYP I 1 (97,)
NE I 1 (256,)
NETYP I 1 (1,)
NN I 1 (289,)
NTYP I 1 (256,)
Element data are contained in the element description tables ETAB.<br>, which consist of relational table data objects. The element tables ETAB.<br> are listed for the first element of the example model:
Relational table "ETAB.1", sub-set 1
Size: 235 bytes, Free table space: 1813 bytes
Keyword Type Size Value(s)
------- ---- ---- -------
EID I 1 (1,)
ITYP I 1 (176,)
NNE I 1 (8,)
NODES I 8 (1,2,19,18)
MID I 1 (1,)
TL I 1 (0.25)
It is implicitly assumed that coordinates are specified with respect to a global Cartesian coordinate system, unless any transformation information is included in the data base. The data set COOR describes the mesh coordinates of branch and their attributes
Solution fields are defined either at the nodes of the branches or element-wise. Element-wise derives quantities are called ‘gradient fields’ or ‘sample point fields’.