Selected Datasets
Element Attributes
All element attributes are stored in the ETAB.<br> relational tables (dictionaries). The tables are accessed either by the MemCom relational table manipulation functions (C API) or with the Python module tb object. ETAB.<br> is an array of NE relational tables, where NE is the number of elements (of the branch).
Common Attributes
Keyword 
Type 
Description 


I 
External element identifier (integer of type 

I 
List of internal element node indexes defining the element,
i.e. the element connectivity list (array of integers of type

Solid Mechanics Elements
If a specific keyword is not listed in one of the sections below, then this keyword is described in the general description of ETAB.<br>.
Keyword 
Type 
Description 


F 
If specified, the array contains rod or cable prestress
information. If 

I 
Element material identifier pointing to dataset


F 
Array 
Keyword 
Type 
Description 

I 
Array containing the optional node eccentricities


I 
Beam start node release code. 

I 
Beam end node release code. 

F 
Array containing the beam local coordinate system
definition. 

I 
Element material identifier pointing to dataset


I 
External property identifier pointing to datatset

Keyword 
Type 
Description 


F 
Array containing optional node eccentricities. 

F 
Optional array containing the element local coordinate system definition. See below. If not specified the material orientation system is the (branch) global system. See additional information on mbase. 

I 
Element material identifier pointing to dataset


I 
External property identifier pointing to dataset PROPERTY.<pid> Element properties. 

F 
Array containing the element thickness at the element nodes. If the array size is 1, the thickness is constant over the element, otherwise a thickness value for each of the element nodes is specified. 
MBASE Additional Information
Unless described otherwise in element specific descriptions of ETAB
,
the first array element of MBASE
contains the type and the remaining 9
array elements the parameters describing the element material
reference coordinate system:
MBASE[0]=0
: The material reference coordinate system is identical to the branchglobal coordinate system, the base vectors being dummy values.MBASE[0]=1
: The material reference coordinate system is defined by 3 base vectorsMBASE[1:3]
,MBASE[4:6]
,MBASE[7:9]
with respect to the branchglobal coordinate system.MBASE[0]=2
: The material reference coordinate system is defined by base vectorsMBASE[1:3]
,MBASE[4:6]
,MBASE[7:9]
with respect to the elementlocal coordinate system.MBASE[0]=3
: The material reference coordinate system is defined by base vectorsMBASE[1:3]
,MBASE[4:6]
,MBASE[7:9]
with respect to the integration point local coordinate system.,MBASE[0]=1
: The material reference coordinate system is defined by angles of orientationMBASE[1:3]
with respect to the branchglobal coordinate system.MBASE[0]=12
: The material reference coordinate system is definedby angles of orientation
MBASE[1:3]
with respect to the elementlocal coordinate system.
MBASE[0]=13
: The material reference coordinate system is defined by angles of orientationMBASE[1:3]
with respect to the integration point local coordinate system.MBASE[0]=30
:MBASE[1]
specifies an (internal) beam reference node identifier which, together with the node identifier of the first beam nodeNODES[0]
(see ETAB.<br>), defines the local beam yaxis.MBASE[0]=31
:MBASE[1:3]
specifies a beam reference orientation base vector \(b\). The beam local coordinate system base vectors (\(e_{x}\), \(e_{y}\), \(e_{z}\)) are then defined as follows: \(e_{x} = P_{2}  P _{1}\), where \(P_{1}\) is the coordinate array of the beam start node and \(P_{2}\) the coordinate array of the beam end node. See also datasets COOR.<br> and ETAB.<br>). Then, \(e_{z} = a \times b\) and \(e_{y} = e_{z} \times e_{x}\). All vectors are normalized.
ENDRELEASE Additional Information
The beam element release flags are bitcoded ENDRELEASE
as
follows: A bit is set to 1 if the corresponding DOF is locked and free
otherwise. Note that bits are numbered starting from 0 and the DOFs
are numbered staring from 1:
Bit 
DOF 

0 
1 
1 
2 
2 
3 
3 
4 
4 
5 
5 
6 
If the ENDRELEASE
parameter is absent all beam DOFs are free.
Materials
DOF Fields
DOF fields are 2dimensional arrays containing F float data pertaining to nodes or elements of the
mesh.One single dataset containing the array is defined per branch and
case, subcase, cycle, and subcycle. The dataset name
gname.br.cycle.subcycle.case.subcase
is composed of
gname
(the generic name as listed below),br
(the branch identifier),cycle
(the computational cycle identifier),subcycle
(the computational subcycle identifier),case
(the ‘load’ case identifier),subcase
ormode
(the ‘load’ subcase or eigenmode identifier)
The FIELDS dataset contains table with attributes describing all defined fields of the current model. The summary of DOF fields below is not exhaustive  it reflects the current standard of B2000++.
Dataset name 
Description 


Displacements and optional rotations (usually) at the mesh nodes. Generated by the iput processor. 

Forces and optional moments (usually) applied to the mesh nodes. Generated by the iput processor. 

Concentrated heat values acting (usually) at the mesh nodes. 

‘Reaction’ forces and moments computed by the relevant solver (usually) at the mesh nodes. 

Concentrated heat values computed by the relevant solver (usually) at the mesh nodes. 

Temperatures computed by the relevant solver (usually) at the mesh nodes. 
Sampling Point Fields
Sampling point fields contain ‘derived’ quantities of the DOF fields and they are stored elementwise in “Array Tables” AT datatype. They can contain a variable number of columns for each element, where a column represents a ‘sampling’ or element integration point. In the current version of B2000++ the sampling points are collected in groups, see the table below.
One single dataset containing the array is defined per branch and
case, subcase, cycle, and subcycle. The dataset name
gname.br.cycle.subcycle.case.subcase
is composed of
gname
(the generic name as listed below),br
(the branch identifier),cycle
(the computational cycle identifier),subcycle
(the computational subcycle identifier),case
(the ‘load’ case identifier),subcase
ormode
(the ‘load’ subcase or eigenmode identifier)
The FIELDS dataset contains tables with attributes describing all defined sampling point fields of the current model. The summary of gradient fields below is not exhaustive  it reflects the current standard of B2000++.
Dataset name 
Description 


Sampling point fields containing strain tensors with 6 components at integration points. The reference system is global. 

Sampling point fields containing stress tensors with 6 components at integration points. The reference system is global. 

Sampling point fields containing strain tensors with 1 component at rod and cable element sections. The reference system is elementlocal. 

Sampling point fields containing stress tensors with 1 component at rod and cable element sections. The reference system is elementlocal. 

Sampling point fields containing 3 force components at rod element sections. The forces are computed with respect to the deformed system (nonlinear analysis). The reference system is global. 

Sampling point fields containing 3 force components at beam element sections. The reference system is global. The forces are computed with respect to the deformed system (nonlinear analysis). Note that stress calculations for beams is not integrated in the B2000++ solver. The Simples bcs module computes section stresses. 

Sampling point fields containing 1 force component at rod element sections in the rod direction (local xaxis). 

Sampling point fields containing 3 moment components at beam element sections. The reference system is global. Note that stress calculations for beams is not integrated in the B2000++ solver. The Simples bcs module computes section stresses. 