XFEM4U Plates

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In the graphical screen slabs can be added very easy by drawing them. Select this item in the function bar. Wikipedia encyclopedia

Plate egdes are drawn as a 'polyline' just as you know it from AutoCAD.The begin node from a following beam is the end node of the last drawn plate edge.

It is possible, but not necessary, to draw nodes before you insert the plates.

You can also start with drawing the plate edges, in this way the nodes will be inserted automatically.

When you draw your first plate edge, the dialog box shown below appears. In this box you can, among other things, insert the material data of the slab. Use the escape-key or click the right mouse button to end the drawing of the plate edges.

As you are drawing a plate edge, help lines (horizontal and vertical) will appear connected to the previous inserted nodes. Often the node, to which you want to draw the beam, has the same x- or y- or z-value as the previous one. In this way it is easy to insert nodes. Obviously you can adapt the coordinates afterwards numerically or by moving the node.

While drawing a new plate edge, a dimension line parallel to the plate edge in one of the main directions x,y or z will appear. You can, just as you know it from AutoCad, immediately insert the distances numerically by entering the value / values from your keyboard. There are 3 possibilities for drawing a plate edge:

1. Drawing a plate edge with a known length in one of the main directions.

The value will appear in the dimension line. Here you can type in the distance. By the use of the enter-key the input is closed and the plate edge with that length will be added.

2. Drawing a plate edge using relative Cartesian coordinates (dx, dy, dz).

First you enter the distance in x-direction. The value will appear in the dimension line. Thereafter you type a semicolon ";" and the distance in y-direction. The value will appear in a second input field. Next you type a semicolon ";" and the distance in z-direction. The value will appear in a third input field. By the use of the enter-key the input is closed and the plate edge is added.

3. Input of relative cartesian coordinates (dx, dy, dz) or absolute cartesian coordinates (x, y, z).

Press the space key and the dialog box below appears. Here you can enter relative coordinates or absolute coordinates directly.

Wikipedia encyclopedia

In this way, you can quickly insert your slab/plate.

The plate can be supported in different ways. By Nodes and/or Plate edge.

You can enter Plate loads and/or Node loads.


Wikipedia encyclopedia


Steel grade

The steel grade of the basic and additional reinforcement.

Creep coefficient

The creep coefficient of concrete. By this coefficient the effective creep coefficient is calculated according to EN 1992-1-1 art. 5.8.4.

You can insert the creep coefficient yourself or you can have it calculated. See Creep. When the creep coefficient is calculated, a detailed calculation according to EN 1992-1-1 B.1 is displayed in the output as well.

Granule diameter

The nominal granule diameter of concrete.


Environmental class

The environmental or exposure class is used for the determination of the required cover. See Exposure classes

Concrete surface

Can be checked, can not be checked or finished


Execution tolerance of the concrete cover in mm


Concrete cover top / bottom in mm


Reinforcement in X- and Y-direction

Basic reinforcement top/bottom

Syntax 1: <amount>x<diameter> [+<amount>x<diameter>...]

Syntax 2: <diameter>-<ctc distance> [+<diameter>-<ctc distance>...]

Syntax 3: <mm2> [ / <diameter>]

Additional reinforcement diameters

The diameters by which the additional reinforcement is designed


Setting which reinforcement is in the first layer

Angle compression strut

Shear reinforcement: Angle compression strut in degrees

Holes in plate

Holes in plate V1.png

Here you can easily enter holes or openings. You can choose from a large number of basic shapes that are parameterized.

Holes in plate V2.png

The position and dimensions of the hole or opening can be adjusted by clicking on the relevant dimension line. The focus in case of multiple holes can be changed by clicking with the left mouse button in the hole contour. If you hold down the left mouse button and move the mouse, you can move the hole graphically. It checks whether holes overlap or cut through the outer contour.

Holes in plate V3.png

Holes in plate V4.png

Holes in plate V5.png

Plate edge

Plate edges are drawn as transparent tubes. By double-clicking on a plate edge (or 1 click right mouse button > Properties) the dialog box below becomes visible.

Plate edge.png

Local to the plate

Setting whether the supports are to be introduced in relation to the local axle system of the plate.

Supports / Restraints

Here you enter how the plate edge is supported. There are many possibilities.

You can use the most common / standard supports:

      Fully fixed Tx=A(Absolute), Ty=A, Tz=A, Rx=A, Ry=A, Rz=A. (That is the default setting)
      Hinged Tx=A, Ty=A, Tz=A. No moments can be transmitted, only transverse and normal forces.

Spring support

You can also enter a spring support. Tx=S(Spring), Ry=S and/or Rz=S. You also give the spring value Kx, Cy and/or Cz in kN/m or kNm/rad.

Local x-axis see Local coordinate system

Plate stresses/forces

See Plate stresses/forces.


See also the background information about the calculation method.