XFrame2D Beams

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BACK

In the graphical screen beams can be added very easily by drawing them. In the function bar you choose this icon: XBeam2DIcon.png

Beams are drawn as a 'polyline' just as you know it in AutoCAD. The begin node from a following beam is the end node of the last drawn beam.

It is possible, but not necessary, to draw nodes before you insert the beams. You can also start with drawing the beams, in this way the nodes will be inserted automatically.

When you draw your first beam, the dialog box shown below appears. In this box you can insert the beam connections and the profile of the beam. Use the escape-key to end the drawing of the beams.

Beam properties

Changing a beam

Changing a beam is possible by clicking on the beam with the left mouse button, and subsequently choose for properties by clicking with the right mouse button. There is a more easy way, namely a double click on the beam. Consequently the following dialog box will be opened.

XBeam2DProperties.png

Beam number

This is the number of the beam.

From node no.

This is the number of the begin node.

To node no.

This is the number of the end node.

Beam angle

This is the angle in degrees with the global x-axis. The direction opposite to the clockwise direction is positive.

Beam type

By the use of the beam type it is shown if the beam in the relevant node is connected by a hinged or a stiff connection.

Indices Description
XBeam2DConnection1.png Fixed connection both sides (default)
XBeam2DConnection2.png Fixed connection at beginning; pinned connection at the end
XBeam2DConnection3.png Pinned connection at beginning; fixed connection at the end
XBeam2DConnection4.png Both sides pinned connection
XBeam2DConnection5.png Fixed connection both sides, ONLY tension
XBeam2DConnection6.png Fixed connection at beginning; pinned connection at the end, ONLY tension
XBeam2DConnection7.png Pinned connection at beginning; fixed connection at the end, ONLY tension
XBeam2DConnection8.png Both sides pinned connection, ONLY tension
XBeam2DConnection9.png Fixed connection both sides, ONLY pressure
XBeam2DConnection10.png Fixed connection at beginning; pinned connection at the end,  ONLY pressure
XBeam2DConnection11.png Pinned connection at beginning; fixed connection at the end, ONLY pressure
XBeam2DConnection12.png Both sides pinned connection, ONLY pressure
XBeam2DConnection13.png Both sides are connected by springs
XBeam2DConnection14.png At the beginning connected by a spring; pinned connection at the end.
XBeam2DConnection16.png Pinned connection at beginning; end connected by a spring
XBeam2DConnection15.png Both sides a pinned connection


Connection

Specifically and only for the spring beam connections, the spring data needs to be inserted.

See Spring beam connection.


Profile name

Here you choose the profile name.


Angle

The angle of the profile. That is the angle relative to the local coordinate system. Normally this is zero degrees. When you want, for example, to enter loaded at its weak axis you fill in 90 degrees.

XBeam2DNewCopy.png

You can also add new profiles, copy profiles and delete profiles. Choose for Properties when you want to adapt the profile data and/or want to select another standard profile type from the profile database.

Elastic soil

This enables you to enter an elastic supported beam. The elastic soil is schematized as a number of spring that can support positive reactions only. The spring distance can adjusted with "Smoothing". The spring value of the spring will be calculated automatically.


Modulus of Sub-Grade Reaction

The modulus of Sub-Grade Reaction in kN/m3.


Global values of Sub-Grade Reaction of several types of soil.

Type Modulus Sub-Grade [kN/m3]
well-graded gravel and gravel / sand mixtures, with little or no fine 80000 - 130000
poorly graded gravel, with little or no fine 80000 - 130000
gravel / sand / clay mixtures 50000 - 130000
well-graded sand and gravelly sand, with little or no fine 50000 - 100000
poorly graded sand, with little or no fine 40000 - 100000
sand / clay mixtures 30000 - 80000
very fine sand, loamy sand 30000 - 50000
solid clay 10000 - 30000
weak clay and peat 0 - 10000

Width

The width of support. Default is the width of the used section but it can be adjusted as well. The width is relevant to determine the spring value.


Smoothing

Default the spacing corresponds with 1x section height. It is possible to change this from 0,5x to 5x section height. This value is relevant to determine the spring value.


Input per beam

When this is switched on the dialog above will be displayed each time a new beam is drawn. This for example enables you to switch the profile.


Table Beams

Beams can also be added/changed in the table Beams in the left bottom. It doesn't matter. It is also possible to change in between graphical drawing and numerical input via tables.

XFrame2DTableBeams.png

Spring beam connection

The following dialogue box is opened.

XBeam2DBeamConnections.png


Here you can adapt the spring characteristics of a spring connection ( for example a semi-rigid fixed connection).


No.

This is the number of the connection, this number is set automatically. From the beams reference is made to this number. In that way the same connection can be applied multiple times. The spring characteristics are only defined one time. So afterwards adapting the spring characteristics is very easy.


Description

Free text space.


Kx

Stiffness in kN/m.


Cy

Momentum stiffness in kNm/rad.