Help >

Opening in webs of beams

Normally, when a 1D member is defined in SCIA Engineer, its cross-section is constant along the whole length. Haunches and arbitrary beams are the only exceptions. But even for these two situations, we usually have a solid web of the 1D member that may change its height or width or both over a specified interval.

Function Opening in beams (Member 1D opening) introduce a qualitatively new feature. This function enables you to define an opening anywhere in the 1D member. Compare the two 1D members in the following picture to understand what the opening means.

$image\BeamOpenings.gif$

Parameters of the opening

General

Name

Specifies the name of the opening

Shape

Rectangular

The opening is rectangular in shape.

$image\BeamOpeningRect.gif$

Circular

The opening is circular in shape.

$image\BeamOpeningCirc.gif$

Cross-section

The shape of the opening is defined by a specific cross-section (e.g. Z-section as in the figure below).

$image\BeamOpeningCSS.gif$

Rectangular shape

Width of the rectangular opening.

Height of the rectangular opening.

Alpha

Inclination of the opening.

$image\BeamOpeningAlpha.gif$

Circular shape

Diameter	Diameter of the circular opening.
Number of edges	The circle of the opening is idealised by a polygon with n-vertices. The number here specifies the number of edges (vertices) of this idealised shape of the opening.

Cross-section-type shape

Cross-section	Specifies the cross-section that defines the shape of the opening.
Alpha	Inclination of the opening.
X-axis reverse	The x-axis of the cross-section making the opening is reversed.

Position

Alignment	Centre Centre-line of the opening is aligned with the centre-line of the cross-section. $image\BeamOpeningAlignmentCentre.gif$ Top Top face of the opening is aligned with the centre-line of the cross-section. $image\BeamOpeningAlignmentTop.gif$ Bottom Top face of the opening is aligned with the centre-line of the cross-section. $image\BeamOpeningAlignmentBot.gif$
Perpendicular offset	Specifies the offset in the position of the opening. The offset is measured along the height of the opening. I.e. if the opening is oriented in Y direction (see parameter below) the offset is made in another direction than for orientation Z.
Orientation	Y The normal to the opening follows the direction of the local Y-axis of the 1D member. The picture below shows a Y-oriented opening with Top alignment. $image\BeamOpeningOrientY.gif$ Z The normal to the opening follows the direction of the local Z-axis of the 1D member. The picture below shows a Z-oriented opening with Top alignment. $image\BeamOpeningOrientZ.gif$
Beta	Rotation of the opening around the X-axis of the 1D member. $image\BeamOpeningBeta.gif$
Depth	Full The opening goes through the whole thickness of the web of the cross-section. (For inclined and rotated openings it cuts the flanges as well). $image\BeamOpeningFull1.gif$ $image\BeamOpeningFull2.gif$ Partial The opening cuts out just a portion of the web. $image\BeamOpeningPartial1.gif$ $image\BeamOpeningPartial2.gif$
Depth value	Specifies the depth of the partial opening. $image\attention_16x16.gif$ The depth is measured from one side-face of the beam cross-section. In order to cut a part of the web from the other side, define angle Beta equal to 180 degrees, which turns the opening around and the depth is measured from the other face.

Calculation

Use for analysis and design

If ON, the opening is used for the calculation and design.

If OFF, the opening is used just for the drawings and the calculation is performed with the original cross-section without any openings and cut-outs.

Number of FE

Specifies the number of finite elements generated along the length of the opening.

Note: For rectangular opening parallel with the longitudinal axis of the 1D member, a single finite element is sufficient. For other configurations, larger number is necessary to model the opening properly.

Note: A 1D member with opening is handled in the same way as an arbitrary member. More specifically General Cross-sections are generated at the position of the opening.

The properties of these General Cross-sections are calculated as specified in Calculation of sectional characteristics . For an exact calculation regarding shear and torsion the FEM analysis should be activated.

FEM analysis

If ON, the sectional characteristics of the General Cross-section generated at the opening are calculated using finite element method.

See separate chapter Sectional characteristics calculated by FEM.

If the FEM analysis is selected, the user can specify additional parameters:

Mesh size

This parameter specifies the size of the finite elements used for the calculation.

Min. point distance

Specifies the minimum distance of two FEM nodes.

Geometry

Position x	Defines the position of the opening in the direction of the local X-axis of the 1D member.
Coordinate definition	Selects if the position is defined in relative (<0, 1>) or absolute coordinates.
Origin	The position can be measured from the beginning or from the end of the 1D member.
Repeat (n)	Defines number of identical openings located one next to each other.
Regularly	If ON, the specified number openings is distributed uniformly along the length of the 1D member. If OFF, the distance between adjacent openings can be defined – see below.
Delta x	Defines the distance between two adjacent openings.

Note: If you need to specify a specific opening that cuts just a specific part of your 1D member (i.e. it does not make just a simple hole), it may be sometimes more efficient to use trial-and-error approach instead of detailed studying of individual parameters.

The procedure to input a new opening in a beam

The beam into which the opening is to be inserted must be already present in the model.
Open service Structure.
Select and start function Member 1D opening.
The Member 1D opening dialogue is opened on the screen.
Fill in the parameters (see above).
Confirm with [OK].
Select the beam(s) where the specified opening(s) should be inserted.

Note: The openings in beams are accessible only if the project level is set to advanced.

SCIA web

Downloads

SCIA is part of the Nemetschek group

Open topic with navigation