10.7 Beam Section

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A section starting with *BEAM SECTION defines a set of beam elements (B23E, B23, B21, B21E), whereby all elements within this set basically have the same properties.

The section keyword *BEAM SECTION has as options

*ELSET=<name>

refers to a name of a set of elements (mandatory)

 

(the same name also has to be defined within an element section)

*MATERIAL=<name>

refers to a material name defining the material of the elements (mandatory)

 

(the same name also has to be defined within a material section)

*SECTION=RECT

rectangular cross section oer alternatively

*SECTION=POLYLINE

cross section shape is described with a polyline

*REINF=<name>

refers to a reinforcement name defining the reinforcement of the beam elements

 

(the same name also has to be defined within a reinforcement section)

 

(this might currently work only together with *SECTION=POLYLINE ($\rightarrow $ open issue))



In case of *SECTION=RECT the first data line describes the following data

$b$,

$h$


with

$b$

cross section width

$h$

cross section height



In case of *SECTION=RECT a following data line describes a reinforcement layer with the following geometric properties

$A_ s$,

$z_ s$,

$\varrho _{eff}$,

$\beta _ t$


with

$A_ s$

cross section area

$z_ s$

height coordinate with respect to the reference line ($z_ s<0$ downward, $z_ s>0$ upward)

 

(reference line goes through the cross section center in case of *SECTION=RECT)

$\varrho _{eff}$

effective reinforcement ratio (used only for tension stiffening)

$\beta _ t$

bond parameter ($\beta =0$: no tension stiffening)



The reinforcement material properties are defined with the material type *RCBEAM. Further data lines may follow for further reinforcement layers if required. The number of reinforcement layers is not restricted.

In case of *SECTION=POLYLINE the data lines describes the following data

$z_1$,

$b_1$

$z_2$,

$b_2$


with up to $n$ data lines ($n \ge 2$, otherwise not restricted) with

$z_ i$

height coordinate, $z_{i+1}\ge z_{i}$

$b_ i$

width of cross section in height $z_ i$



The beam’s reference line goes through $z=0$. A reinforcement is defined with a reinforcement section starting with *BEAM REINF.

The section keyword *BEAM SECTION has no own keywords.

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