2.17.2 Welded uniform cross-section beams in Tekla Structures
The consecutive method is a more intense one though the most correct
for building up welded uniform cross section beams. It is important to
consider that in practice real profiles are created of rolled metals, provisionally
cutted and welded on to get the I-beam shape.
Thus it is of a high importance to consider the rolled metal in the statements
as well as execute modelling the I-beams of the rolled metal sheets. It
is possible to create rolled metal drawn up by a polygon, but in this case
we will have to manipulate many points, which is not a convenient situation.
Thus during modelling non uniform cross section beams it is more
convenient to use the beam tool configured at a specific profile type,
which is considered in the material statements as rolled metal.
Let’s firstly create an uniform cross-section beam, which geometrically
is similar to a standard beam, but is composed of 3 distinct rolled metal
sheets welded on togher into an assembly.
Go to the view plane and create a simple beam of 1000 mm length.
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At the "Profile catalog", select the parametric plate profile.
Depending on the localization package of the Tekla Structures, there might
be various titles set out for these profile types. These profiles
are necessary for substituting the wide profile range. Thus for modeling
a rolled metal list, is it sufficient to indicate only the length and width
parameters for the initial sheet part.
Except for executing modeling rolled metal sheets, it is not recommended
to use parametric profiles, as they do not contain any ISO information
and other service system information.
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Let’s apply the selected profile to our model. Pay attention to
the fact that the first digit stands for the thickness parameter of the
part, not its width. In the below picture you can see the very error committed.
Thus in the rolled metal specification, a sheet of 200 mm thickness is
indicated. Write into the profile field the thickness value first,
but the width value right after the symbol “*”.
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Make sure that the first digit is of the smallest value.
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Subsequent to pressing the “Modify” button, you can see no
visual changes in the model, but it is of a high essence for creating the
material reports and statements: we use the material of 20 mm thickness,
but not of 200mm: “—20*200”.
Rotate the part created in the way to see it into the I-beam flange position.
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The scheme for substituting the rolled metal profile at a welded uniform
cross-section beam. Redpoint stands for indicating the building up line
of each profile with account for the offset.
Select the object and draw up a new beam by taking the account of the
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Change the beam's profile to “—16*300” and its class
to 6 (yellow). Set out by your own the position parameter values
concerning the profile reference line.
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Configure the “At depth” value as it is shown below:
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Select the upper flange part. Create one more beam taking into account
the reference line of the initial object and its starting and endpoint
sequence.
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Configure the new beam’s profile similar to the upper flange, indicating
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Let’s weld up parts into an assembly, where the beam's wall
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Thus we have created a beam made of rolled metal sheets. In the specification,
this beam is reflected as the rolled metal, not as an I-beam. Such beams
are commonly used upon a tailored object request.
Here it is essential to clarify, why during creating such a beam we were
taking account of the initial beam reference line, as it should seem easier
to create profiles at an arbitrary position and move them into a required
position by using the Ctrl+M hotkey combination, and the latter would not
be a mistake.
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Go to the view plane by pressing the Ctrl+P hotkey combination and create
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Thus we can see the "Side view" of the beam. Select all 3 components
of the assembly, and by holding on the "Alt" key pressed, select
three right points by framing them.
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Move the points at 300 mm upwards to get a sloped beam.
Thus building up parts with the account to the reference line comes in
handy, and creating a sloped beam does not require using the “Rotate”
tool.
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If we would not take account of the reference line of the initial part
when creating the other assembly components, we would be supposed to adjust
each part separately or to use the “Rotate“ tool.
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During modeling a project, there can be used various beams, composed of
the rolled metal sheets. It is of no use creating a new profile, as it
is enough to copy the one already created and configure its profile values
as required. Copy the sloped beam to the right at 1300 mm.
Note that welds are copied automatically along with the beam.
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Set out different thickness and plate width values, by configuring the
plate profile to “—25*300”. Change its class to
9 for a better visual representation.
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Modify the profile of the beam's wall to “—20*350”
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Let’s set up the offset values of the plate taking into account
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Proceed to configure the bottom flange plate according to the respective
characteristics of the upper flange, and indicate the offset value equal
to the beam's wall height+ the upper flange thickness sum of values:
350+25=375.
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Tekla Structures v2021
Thus during modeling, it is possible to create various welded uniform
cross-section beams, multiply them by copying and configure them as required.