Did you know you can use Consteel to run second-order and buckling analyses on specific parts or elements of your model by defining a Custom Portion for the portion of interest?

The workflow starts in the Portions Manager, where you can manually group structural members, frames, columns, beams, bracings into Custom Portions. These are fully user-defined and, importantly, only these custom portions can be directly used for analysis. This allows you to isolate exactly the structural subsystem you want to investigate, without being constrained by the full model.

Once a portion is defined, it can be selected in the Analysis Settings, where you can choose whether second-order and buckling analyses should be performed on the entire model or only on the selected portion. The solver will then consider only that subset of elements when assembling the stiffness matrix and evaluating stability behavior.

Running these analyses on specific portions has clear engineering advantages. Second-order effects and buckling phenomena are often governed by local structural behavior, such as a critical frame, a bracing system, or a column group, rather than the entire structure. By isolating these regions, you can:

• reduce computational effort and analysis time, especially for large models
• focus on the most critical load paths and instability mechanisms
• perform faster iterations during design refinement
• avoid unnecessary influence from non-relevant parts of the structure

This targeted approach leads to more efficient and controlled stability analysis, particularly when investigating sensitive or highly utilized structural components.

Download the example model and try it!

Download model

If you haven’t tried Consteel yet, request a trial for free!

Try Consteel for free

Did you know that you could use Consteel to build 3D models with smart link elements which automatically adapt the model when profiles are changed?

Link elements are used to connect members that are not directly joined. In Consteel, three types of link elements are available: Link, Smart Link, and Constraints.

A smart link is a dynamic connection element designed to simplify the management of geometric changes between connected members. It automatically follows the movement, rotation, or profile changes of the primary member it is attached to, while also ensuring that any connected secondary member adapts accordingly.

A common application is connecting a main beam to a purlin or other secondary elements, with smart links positioned at specific points. They enable easy attachment of additional members while preserving the defined eccentricity, and automatically adapt to any changes in the main beam’s geometry or profile.

The Smart Link function, located on the Structural Members tab, opens the Edit Smart Link dialog box after activating the command. This allows you to:

• define the eccentricity of the link relative to the main section

• set the connection type in the Release field

The connection position can be specified manually or left to default automatically to the edge of the main member.

Defining the connecting section is optional. When specified, an eccentricity can be assigned, and the program automatically determines the link length based on the section height and reference point.

Smart links can be placed individually by clicking on a member or in groups by specifying distances from the member’s start. Any placement conflicts are indicated by a warning.

By combining associative behavior with precise control, Smart Links support efficient and reliable 3D modeling in Consteel. They help maintain structural intent throughout design changes, reduce manual corrections, and improve overall model consistency.

For workflows where geometry evolves and secondary members must remain accurately connected, Smart Links provide a clear advantage and enable a more resilient and adaptable modeling process.

Download the example model and try it!

Download model

If you haven’t tried Consteel yet, request a trial for free!

Try Consteel for free

Did you know that you could use Consteel to Consider the shear stiffness of a steel deck as stabilization for steel members?

In many practical steel structures, trapezoidal decking is treated only as a load-bearing surface. In reality, when properly connected to the supporting members, it behaves as a shear diaphragm and contributes to the overall stability of the structure. This effect can be directly taken into account in Consteel by applying shear field stiffness to beam elements.

The stabilizing effect comes from the in-plane shear stiffness of the deck. Under horizontal loading, the sheeting deforms and transfers forces between structural members. This behavior can be described by a single parameter, the shear stiffness (S), which represents the resistance of the diaphragm against deformation.

The overall stiffness is influenced by several components, including the shear deformation of the sheet, profile geometry, fastener slip, and connection flexibility. These contributions together define how effectively the deck can restrain phenomena such as lateral-torsional buckling.

A key requirement for this behavior is proper fastening. Typically, the sheeting must be connected along its edges and fixed to supporting members at each rib to ensure reliable diaphragm action.

In engineering practice, shear stiffness is determined using standardized or manufacturer-based methods rather than detailed analytical models. Consteel supports several established approaches:

• Schardt/Strehl method (DIN 18807), based on parameters describing shear and warping deformation
• Improved Schardt/Strehl method, including the effect of fastener spacing
• Bryan/Davies method, considering additional structural parameters
• Eurocode-based method, using general geometric properties of the sheeting

These methods differ in complexity and required input data, but all aim to provide a realistic stiffness value for use in global analysis. If the sheeting is not fixed at every rib, the calculated stiffness must be reduced accordingly.

The shear field object in Consteel allows engineers to include the diaphragm effect without detailed shell modeling. The calculated shear stiffness can be assigned directly to beam elements, providing additional lateral restraint.

The process involves selecting a trapezoidal sheet profile, choosing the appropriate calculation method, and defining the relevant geometric and connection parameters. The software then determines the stiffness and incorporates it into the structural model.

Including shear stiffness in the analysis can lead to higher critical load factors and reduced displacements, resulting in more efficient structural designs. However, it also means that the decking becomes part of the stabilizing system.

Any later modifications to the sheeting, such as openings or changes in fastening, may reduce this effect and should therefore be carefully assessed.

The shear stiffness of trapezoidal steel decking provides a measurable and often significant contribution to structural stability. By incorporating this effect in Consteel, engineers can achieve more realistic analysis results and optimize their designs while maintaining structural safety.

Download the example model and try it!

Download model

If you haven’t tried Consteel yet, request a trial for free!

Try Consteel for free

Introduction

Are you wondering how a web opening would influence the lateral-torsional buckling resistance of your beam? Check it precisely with a Consteel Superbeam based analysis

It is often required to let services pass through the web of beams. In such cases the common solution is to provide the required number of opening in the webplate. Such an opening can have a circular or rectangular shape, depending on the amount, size and shape of pipes or ventilation or cable trays.

Beams must be designed to have the required against lateral-torsional buckling. The design procedure defined in Eurocode 3 is based on the evaluation of the critical bending moment value which provides the slenderness value, needed to calculate the reduction factor used for the design verification.

There is no analytical formula provided in the code for beams with web openings. Would the neglection of such cutouts cause a miscalculated and unsafe estimation of the critical moment value?

The following demonstration will be made with a 6 meters long simple supported floor beam with a welded section.

Exposed to a linear load of 10 kN/m, the critical bending moment value of the solid web beam can be obtained by performing a Linear Buckling Analysis (LBA) with Consteel.

Download model file

The obtained critical multiplier for the first buckling mode is 3.00 which means that the actually applied load intensity can be multiplied by 3.00 to reach the critical load level. The corresponding critical moment will have the value of M_cr = 3.0 * 47.18 = 141.54 kNm yielding a slenderness of 1.286 (M_pl,Rd = 234.20 kNm) and a lateral-torsional buckling resistance of 0.394 * 234.20 = 92.27 kNm. With this value the actual utilization ratio is at 51%.

How would this value change if a rectangular opening needs to be cut into the web of this beam?

Analytical formula for critical bending moment

By looking to the analytical formula (ENV 1993-1-1 F.4) to calculate the critical moment of double symmetric sections loaded at eccentric load application point it becomes obvious that the section properties having effect on the moment value are I_z, I_w and I_t.

An opening in the web has no effect on the first two values and has very little effect on the last one. As it has been already shown in previous article, the presence of such an opening can have effect on the vertical deflection, but as long as the lateral stiffness of a beam is much lower than it’s strong axis stiffness, the vertical deflections can be neglected when the lateral-torsional buckling resistance is calculated. The usual linear buckling analysis (LBA) performed also by Consteel neglects the pre-buckling deformations.

Therefore one can expect that in general web openings can be disregarded when the critical moment value is calculated.

Analysis with Consteel Superbeam

Beam finite elements cannot natively consider the presence of web openings. In order to obtain the precise analysis result, it is possible to use shell finite elements. The new Superbeam functionality comes as a solution in such cases. Instead of using beam finite elements, let’s use shell elements!

Opening can be positioned easily along the web, either as an individual opening or as a group of openings placed equidistantly. The opening can be rectangular, circular or even hexagonal. Circular openings can be completed with an additional circular ring stiffener.

The rectangular opening for this example can be easily defined with this tool. As there is no need to provide any additional opening on the remaining part of the beam, only the first part which includes the opening will be modelled with shell elements and the rest can still be modelled with beam finite elements. Using this technique, the total degrees of freedom of the model can be kept as low as possible. When using Superbeam, the designer has the choice whether to use beam or shell finite elements, as appropriate.

gate

Example hall model for trying the smart link feautre in Consteel

Watch our user guide about How to use the smart link feature to learn more.

gate

Example model for trying the smart link feature in Consteel

Watch our user guide about How to use the smart link feature to learn more.

gate

Introduction

In the last years, freeform architecture became more and more popular. A variety of complex geometric shapes are used for the facades of buildings, which brought the demand of new, innovative tools and solutions for modelling of these structures too. In Consteel we have developed such functions to make the engineers‘ work easier.

Section orientation

Orientation of the sections is always a problem. We have implemented a tool, with which the rotation of the sections can be done automatically. Sections can be rotated perpendicularly to the surface of the freeform shape of the structure. Z axis will be perpendicular to the surface formed by the connecting beams.

Load transfer surfaces

Covering a freeform structure with load transfer surfaces -like in the picture below-manually, would take a lot of time and effort. Our tool for multiple load transfer surface placement gives you a quick, easy and effective solution for covering your freeforms.

gate

Introduction

The Frame corner wizard is a useful additional function for modelling and analyzing the corner region in order to consider its special behavior.

What is it for

The frame corner zones have usually significantly different behavior than the beam elements connected to each other without significant angle between their reference line. Frame corner wizard recognises the corner regions and applies special methods during modelling, buckling analysis and global checks. Using this function will provide very similar analysis results compared to where the frame is modelled with shell elements.

But in order to that, the topology of the frame corner must be defined by the user. Four different types can be chosen. The 7. DOF displacement is transferred differently in every case. To learn more technical details of the frame corner types, please see our user manual.

How to use it

At first define Portions of the model containing all the structural elements you intend to connect with the same type of corner topology.

gate