Graitec, as a global software editor in the Design, Structural, Fabrication, and Data Management arena organizes an international contest dedicated to structural engineers and design offices.
The award is for the best practical use of Advance Design in Steel / Timber / Concrete design projects. This contest is open to customers and students who want to showcase their experience and technical knowledge through a project executed in Advance Design software. The projects will be judged by a professional jury. The final nominees and the winning projects will be made public to a wide audience through extensive marketing including social media.
• 30.7.2021 Entries close – Deadline for project submission
• 10.9.2021 Project Confirmation – Confirmation and announcement of projects accepted
• 11.10.2021 Jury Deliberation – Selection of winners
• 19.10.2021 Announcement of Results – Announcement of winners at the Advance Design User Summit 2021
Contest criteria:
The independent contest jury will gather in October 2021 to evaluate the projects. The judging will be done under the guidance of a dedicated Graitec Group representative. The representative is in charge of the contest. The jury will evaluate the projects taking the following criteria into consideration:
Technical level of the design, detailing and/or calculations.
Originality and prestige of the project.
Attractiveness, detail and presentation of the project.
Optimal use of software’s functionality.
The “story” behind the project – difficulties overcome, innovative approaches, benefits gained, etc.
Jury:
An independent and international jury composed of academics and professionals in the field will judge the submitted entries. Meet the members of our jury:
Francis Guillemard – Jury Chairman / GRAITEC President of the Group and Chairman of the board / France
Rawad Assaf / ISSAE – CNAM Liban/ Lebanon
Olivier Chappat / Bouygues Bâtiment Ile-de-France / France
Piotr Nazarko / Rzeszow University of Technology / Poland
Rodrigue Coyere / EIFFAGE CONSTRUCTION Structural design office / France
Daniel Bitca / Technical University of Civil Engineering Bucharest / Romania
Jiri Bendl, GRAITEC, Vice President SIMULATE comments: “Through the Advance Design Award organizations we want to reward our customers for being members of the ever-growing SIMULATE community and we want to encourage students to use the best possible tools for structural analysis. It is a great pleasure for me to be part of this project!”
About GRAITEC
Founded in 1986, GRAITEC is an international group (13 countries worldwide – 48 offices) helping construction and manufacturing professionals to successfully achieve their digital transformation by providing BIM and Industry 4.0 software and consultancy. GRAITEC is a developer of high-performance BIM applications as well as an Autodesk Platinum Partner in Europe and Gold Autodesk Partner in North America and Russia. With more than 550 employees including 200 BIM consultants, GRAITEC is an innovation-focused company whose products are used by more than 100,000 construction professionals worldwide.
According to EN1993-1-3, formula (10.1b), the shear stiffness of trapezoidal sheeting connected to a purlin may be calculated as :
With:
t : thickness of sheeting (in mm)
broof: width of the roof (in mm) (roof dimension parallel to the direction of the panel ribs)
s: spacing between purlins
hw: profile depth of sheeting
Assume a purlin connected to the following trapezoidal sheeting, at each rib:
Roof width : 6,00m
Distance between purlins : 2,50m
This result sin a shear stiffness of 8361 kN.
Formula (10.1b) assumes the purlin is connected at each rib to the trapezoidal sheeting :
Purlin connected at each rib
In case the purlin is not connected at each rib but at every other rib, only a small portion (20%) of this S stiffness can be considered :
Purlin connected every other rib
If this value exceeds a certain value (Smin), the purlin may be regarded as laterrally restrained in the plane of the sheeting.
Assume an IPE140 purlin:
Iw = 1980 cm6 (warping constant of the purlin)
It = 2,45 cm4 (torsion constant of the purlin)
Iz = 44,92 cm4 (minor axis inertia of the purlin)
h = 140 mm (height of the purlin)
L = 6,00m (span of the purlin)
In our case, S > Smin. The condition is met and the purlin may be regarded as laterally restrained.
In Advanced Design, such a purlin may have its ‘Continuous restraint along flange’ property enabled on the upper flange :
For more complex cases, when the member is prone to torsional effects (Channel or Z section for example), a more sophisticated calculation may be required (2nd order calculation with warping).
In this case, the shear stiffness (S) may be taken into account as the ‘Shear field’ parameter from the ‘Advanced stability’ dialog :
In order to perform second order analysis on steel elements in Advance Design, Steelwork Design “To calculate” option must be activated from the element’s property list.
Figure 1 – Steelwork Design Activation
This feature is available either for each individual steel profile or for a multiple selection, by checking 2nd order with warping and imperfections checkbox, setting the Number of iterations and Stability 2nd order parameters.
Figure 2 – Advance Stability Activation
The “Advanced stability (2nd order)” parameters can be found in the Steelwork Design section of the property sheet for steel members.
Figure 3 – Advance Stability Options
(1) Checking the “2nd order with warping and imperfections” box will perform the analysis of the selected members during the steel calculation sequence. (2) The 2nd order analysis being an iterative process , the user can set the maximum number of iterations.
The 2nd order analysis uses the user-defined imperfections in order to determine the final 2nd efforts. The imperfections are applied step by step, incrementally, until the final imperfection defined by the user is achieved. At every iteration, the 2nd order efforts are recalculated starting with the previously calculated efforts. Calculations are made until convergeance – defined as the difference between 2 succesive iterations (automatically managed internally by the solver) – is achieved, or until the maximum number of iterations is achieved.
(3) The “Stability – 2nd order parameters” will give access to a dialog where the user can define the various parameters to be considered during the analysis of the selected members. The definition dialog will show 4 tabs: • Nodal springs • Bedding • Imperfections EC3 • Loads offset
Although the “Advanced stability” from Advance Design feature considers the individual member, the intersections with the other elements are of course taken into account. In fact, the intersections are turned into nodal springs.
Figure 1 – Auto Detect Spans Option
The selected member has intersections with other elements at x = 0.00m and x = 4.00m.
The “Auto-detect spans” button enables the users to see the intersections and alter the behavior of the corresponding springs.
The users can also add or delete nodal springs (only user-added nodal springs can be deleted) from the grid using the “Add” and “Delete” buttons. Moreover, they can reset the grid with the help of the “Reset” button.
Note: Even if the user does not open the Advance stability definition parameters, Advance Design will automatically take into consideration the intersections with the other elements during the analysis.
Note: If geometrical parameters are modified after the “Advance Stability” option is checked for steel members, “Reset” and “Auto-Detect Spans” options must be selected in order to reinitialize the position of the nodal springs. Any modifications made in the Advance stability window will be reset to default. Otherwise, the calculation will not be successful.
For each nodal spring, the user can set the status for each of the seven DOF.
Tx, Ty and Tz stand for the displacement along the x, y and z axes respectively
Rx, Ry and Rz stand for the rotation about the x, y and z axes respectively
Rw is the warping
Figure 2 – The seven Degrees of Freedom
Available statuses are:
Free: enables the release for the considered degree-of-freedom ;
Fixed: disables the release for the considered degree-of-freedom (this translates into a very high stiffness);
Auto: lets Advance Design automatically determine whether the degree-of-freedom is free or treated as an elastic release (the stiffness of which is automatically computed by Advance Design for each combination);
Elastic: defines an elastic release for the considered degree-of-freedom (stiffness imposed by user).
When set on “Auto“, Advance Design is able to compute the appropriate stiffness of the release as Force/Displacement, resulting in a stiffness value for each combination.
Figure 3 – Stiffness definition
Warning: the “Auto” status means that the “Advanced stability” feature will attempt to re-create the boundary conditions based on the Forces and Displacements diagrams from the global model.
This can be challenging in some cases as the automatic determination has its own limitations.
For example, zero forces on a given node can either mean:
The degree-of-freedom (DOF) is free;
The DOF is fixed but no force was acting in the given direction.
Therefore, we would advise the users to manually set the free DOF”s on “Free” whenever possible as the “Advanced stability” feature is not able to import the boundary conditions defined on the member in the global model. The “Advanced stability” feature can only deduce the boundary conditions from the Forces and Displacements diagrams it imports from the global model.
We would also advise the users to make sure the member does not feature a free “Rx” DOF on both ends as this could lead to a numerical instability if no other intermediate nodal spring exists.
Setting the “Rx” DOF on “Fixed” can be a solution when the “Auto” detection method fail.
Figure 4 – Degrees of Freedom Status
The “Position” property enables the user to define an eccentric spring.
Eccentricity is meant in the z direction (Upper fiber, Neutral, Bottom fiber or User value).
Figure 5 – Nodal Springs Position Eccentricity
Stiffness auto correction There are cases when, by activating the “Auto-detect spans” option, the automatically calculated stiffness does not meet the minimum criteria in order to successfully perform the 2nd order analysis (for example, when displacements are automatically imposed at an element”s ends for which the automatically calculated stiffness is insufficient). By activating the “Stiffness auto correction” option, the program automatically imposes a minimum stiffness in order to successfully perform the analysis, but only when the values are very small.
Figure 6 – Stiffness Auto Correction Activation
Generally, the warping DOF (degree-of-freedom) is free and fixing it requires special rules for detailing, like the end plates, beam extensions, flat stiffeners.
The reinforced concrete linear elements are usually characterized by square, rectangular or circular cross-sections. Advance Design computes the reinforcement for such elements with the Reinforced Concrete (RC) Design expert. For irregular, user defined cross sections, the RC design falls outside the standard procedure. Therefore, the real reinforcement may be determined following an iterative process, as described in the next steps:
1. Add a new user defined cross-section – follow the steps from Figure 1
Figure 1 – Steps to define a new user section
2. Define the cross-section geometry (shape and reinforcement position) and material in the Cross Sections module: draw the shape by point coordinates, define the reinforcement (automatic or manually) and concrete cover, define the material and calculation settings.
Note: It is recommended to define the initial reinforcement from the minimum reinforcement area.
Figure 2 – Define the cross-section shape and place the reinforcement
3. Set parameters and calculate the cross-section properties
Figure 3 – Calculation settings
4. Export the cross-section to the Advance Design library
Figure 4 – Close and export the cross-section to Advance Design library
5. The user defined section is attributed to the desired linear elements (columns). Run FEM and RC Design analysis.
6. On the selected element, check the RC design – element reinforcement results. The real reinforcement (imposed) can be compared to the theoretical reinforcement (computed). The verification can be observed on the interaction curves also. The section solicitation point should fall inside and close to the capacity curve (My/Mz, Fx/My, Fx/Mz), for a safe and economic design. If the imposed reinforcement does not satisfy these conditions, the initial reinforcement is increased: restart from Step 2.
In this short article, we will look at one of the model validation methods available in Advance Design – displaying modelled elements in color according to selected criteria. Although this functionality is more general and can be used simply to improve the way a model is presented in a view or for documentation, today we will focus on its advantages for model verification.
Let us start with the topic of verification of local system of axes of surface elements. Checking and eventual change of local systems is an important step in the verification of the model, because by proper arrangement of local systems we have control over the uniformity of the FEM results and the reinforcement directions. Each modelled planar element has its own local system of axes, which is set automatically. Knowing the basic rules of automatic local axis system setting (as for example that the x-axis of the local system is usually defined along the first edge of the drawn contour) we can often control it ourselves. However, this is not always convenient or possible, especially when the model has been imported. Checking the local layout of axes for one or more elements is not a problem – we can simply select a surface element and we see its local axis symbol by default. The colors of the axes correspond to the colors of axes of the global coordinate system, i.e., the red axis is local x, the green one is local y and the blue one is local z.
However, it is much more interesting how we can quickly check the local axis settings for a larger number of elements / for the whole model. To do this in Advance Design, we can use a very versatile tool to display objects in color according to selected criteria, available in the Display Settings window. In the ‘Color’ command group, there is a list for selecting coloring criteria, as well as additional options including displaying a legend and displaying the element’s local system axis during element selection.
For our purposes, of the many criteria available here, three will be useful to us: Local x orientation, Local y orientation and Local x orientation. All these modes are used to indicate in which direction the axes of the local system are oriented relative to the global system.
Take a look at the image below showing an example of the effect of using the ‘Local x orientation’ option.
The surface elements are colored and thanks to the legend we can immediately see how the local x-axis is oriented. For example, dark blue means that the local x-axis is pointing in the Y- direction of axis of the global system, light blue means that it is pointing in the Z- direction (down), while red means that it is pointing in the Z+ direction (up). We can easily confirm this just by selecting elements, as then we can see symbols of local systems.
If we now want to unify the orientation of the local axes, all we need to do is select the relevant elements, which is very easy thanks to the colors, and then choose one of the dedicated commands: Local Axis or Local Axis on direction.
On a similar basis, we can verify the orientation of the other axes of the local system of planar elements, but in the same way we can verify the local systems of linear elements. Of course, for this purpose, it is best if we filter out only the linear elements for presentation. But the same types of coloring styles as for surface elements can be used for this purpose.
The layout of local axes is not all that we can verify with coloring. The same tool can be used to verify the correctness of the modeling according to other criteria – for example thicknesses.
On the same principle, we will also check the cross-section of linear elements or the material that has been assigned to different elements of the model. But that’s not all. In a similar way, we can color elements according to their type, system assignment, or super element affiliation. And, other objects, such as loads by category or steel connections by type. I recommend that all Advance Design users become familiar with all the available coloring criteria because using them increases the control over the model.
In order to simulate the membrane effect in a structure in Advance Design, “DOF (Degree of freedom) constraint” object can be used with the Tx and Ty translations restrained. DOF constraint object is also named as Master-Slave connection. The command can be found in “Objects” ribbon tab:
Figure 1 – DOF constraint localization
The following properties regarding restraints definition are defined for the “DOF constraint” (Master-Slave connection):
Figure 2 – DOF constraint properties
For example, the response of the DOF constraint is compared with the response of a membrane in a simple 3D structure subjected to lateral loads. In this model, the elements’ self-weight is not considered.
Figure 3 – DOF constraint model view
Figure 4 – Membrane model view
Since the master-slave connection imposes to all component nodes the same DOF restraints (translations/rotations), the master node can be placed anywhere on the perimeter. In order to simulate the same response, the nodes must be placed on the same position as the mesh nodes of the membrane:
Figure 5 – DOF constraint mesh view
Figure 6 – Membrane mesh view
The similar response of the two objects (master slave connection with Tx and Ty translations restrained and membrane) can be verified by comparing the results of the FEM analysis:
Figure 7 – Displacements comparison between the two models
Figure 8 – Axial force comparison between the two models Figure 9 – Bending moments on columns comparison between the two models Figure 10 – Bending moments on beams comparison between the two models
BIM WORKFLOW WEEK is an online event organized by GRAITEC for structural engineers and detailers. Nowadays, you can streamline your BIM workflows using Graitec and Autodesk technologies together. Bridge the gap between all stakeholders and discover how you can develop and improve your construction projects in a digital thread!
Each day we will run a webinar to show how easy it is to streamline your daily work! We show how to apply a complete BIM workflow from design to detailing on all your projects during the webinars! Don’t wait and register today!
BIM WORKFLOW WEEK AGENDA:
Monday – 15/03/2021 – CREATE YOUR BIM MODELS WITH REVIT AND SIMULATE THEM WITH ADVANCE DESIGN
Are you a structural engineering company doing construction projects with Revit® from Autodesk in a BIM environment? In this webinar, we will propose you a way to streamline your projects, starting to CREATE BIM data in Revit, exporting it to Advance Design to SIMULATE your building and synchronize back in Revit all changes. Discover how easy it is to link Autodesk Revit and Graitec Advance design to simulate and optimize your steel an concrete projects.
Tuesday – 16/03/2021 – ENRICH YOUR 3D BIM REVIT MODEL WITH ANALYTICAL DATA AND RESULTS USING ADVANCE DESIGN
In this webinar, we will go deeper in the integration between Autodesk Revit and Advance Design: exchanging and synchronizing geometrical data is a good point but is not enough to enable a real BIM structural workflow. During this session, you will discover how to enrich your Revit model with finite element results and theoretical reinforcement values using Advance Design with an effective synchronisation mechanism controlled by the user!
Wednesday – 17/03/2021 – APPLY AN EFFECTIVE BIM WORKFLOW FOR ALL YOUR REBAR PROJECTS IN REVIT!
In this BIM era, it’s time for you to manage your rebar projects with 3D models using Autodesk Revit®! Join us to this webinar and discover how you can use the Autodesk platform and Advance Design together to produce 3D Design-driven rebar cages for Beams-Columns-Footings-Slabs-Walls & Shear Walls, automate the drawing views creation with all tags and annotations, produce final drawings and manage in real time all your rebar projects!
If you’re a structural engineer or a steel detailer using Advance Steel and want to save time, cost and reduce your carbon footprint, Graitec now offers a solution to complement and optimise your current workflow. To facilitate analysing these complex 3D steel connections, Advance Steel joints can now be exported to Graitec Advance Design Connection!
Friday – 19/03/2021 – APPLY A COMPLETE BIM WORKFLOWS FROM DESIGN TO DETAILING ON ALL YOUR STEEL PROJECTS!
In this webinar, we will go through a complete BIM workflow from design to detailing using Autodesk Advance Steel and Graitec Advance Design together. You will discover how easy it is to design and optimise a steel structure with Graitec Advance Design, including steel joints. Then, we will end by exporting the model to Advance steel to create drawings, BOM lists and CNC files fir the fabrication.
The shape optimization calculation for steel elements can be performed in Advance Design considering the condition of maximum deflection. Then, new cross-sections are searched if the deflection ratio is greater than the set limit (default 100%).
Thanks to this option from Advance Design, it is possible to optimize steel elements while using more criteria at the same time, like searching and selecting for profiles that must meet the conditions for maximum load capacity (strength/stability) and maximum deflection, independently or at the same time. This is especially useful for design of steel structural elements that exceed the maximum deflection while meeting the load capacity condition.
The optimization assumptions can be found in the Optimisation tab from Steel Design Calculation Assumptions dialog. Under the “Find new sections” paragraph, a new option is available to activate the deflection criterion and to set the maximum allowable deflection ratio considered for the cross section optimization. These assumptions apply to all steel members from the model which have Steelwork DeDefault optimization assumptionssign option from the element’s properties activated. The limits imposed in this tab apply to all cross sections as a group and cannot be applied differentially for singular element.
By default, the deflection ratio optimization is unchecked:
Figure 1 – Default optimization assumptions
By checking the “if the max/all deflection ratio is greater than:” option, the user can impose the maximum ratio.
Figure 2 – Activation of the deflection optimization criterion
Once the steel calculation is completed, the strength/stability and deflection work ratios of steel elements are compared with the specific criterion, and other cross sections that meet the imposed conditions are suggested. The results of steel elements optimization are displayed in the Suggested shapes dialog, displaying the current strength/stability and deflection ratios. If the ratios are greater than the imposed limits (100% by default), the current ratio is displayed in red. For such cases, if the deflection criterion is activated, the next cross section from the catalog that will meet the required criterion will be suggested, displaying also the ratio for that section.
Figure 3 – Suggested shapes according to selected criterion
By opening the Accepted solutions flyout, we can select the suggested shape or other section from the same catalog.
Figure 4 – Selection of accepted solutions
After accepting the suggested (or imposed) sections, from the Accept all option, a new steel calculation is required, in order to recalculate the new sections and have correct results in the shape-sheet of the elements and reports. This optimization sequence is directly dependent with the sorting mode selected in the Sort profiles tab from steel Calculation assumptions. By default, the “Envelope criterion” option is selected, which means that the suggested profiles will meet both deflection criterion and strength/stability criterion.
Figure 5 – Default sort mode for section optimization
If the Envelope criterion is selected, the new profiles are suggested from both cases, if the deflection or strength/stability criterion are exceeded:
Figure 6 – Suggested shapes according to envelope criterion
If the Deflection criterion is selected, then the new profiles are suggested only if the deflection ratio is exceeded:
Figure 7 – Suggested shapes according to deflection criterion
If the Strength/stability criterion is selected, then the new profiles are suggested only if the deflection ratio is exceeded:
Figure 8 – Suggested shapes according to strength/stability criterion
In order for the deflection criterion based optimization to be computed, both Steelwork Design and Deflections options from element’s property list must be checked. The optimization based on deflection will be made according to the parameters introduced in the property list:
Figure 9 – Element property check
If the deflection verification is unchecked for an element, then “N/A” (Not available) message will be displayed for the Deflection work ratio in the Suggested shapes dialog.
This new feature makes result checking easier, thanks to the possibility of presenting a ratio for deflection during shape optimization. It also gives you the possibility to select optimal steel profiles considering the deflection. Various options from the Assumptions dialog help you get specific results for the steel elements used in design and enhance the workflow.
The present article explains how to determine wind loads on vaulted roofs at the Eurocode 1. Specifically, we will show how to use Figure 7.11 from EN1991-1-4, which provides the external pressure coefficients on vaulted roofs with rectangular base:
We will consider a structure with following dimensions:
f = 2,51m
h = 3,20m
d = 9,60m
The developed length of the vaulted roof will be split into 4 equal parts, for zone A, zone B (repeated twice) and zone C:
For each of these zones, the external pressure coefficient (Cpe10) is read on a graph, depending on the f/d and h/d ratios.
In our case:
f/d = 2,51 / 9,60 = 0,26
h/d = 3,20 / 9,60 = 0,33
For zone A
We start on the f/d axis until we reach the two diagrams related to zone A:
For h/d = 0, we read Cpe10,A = +0,42
For h/d ≥ 0,5, we read Cpe10,A = +0,16
We then perform a linear interpolation because in our case, 0 ≤ h/d ≤ 0,5:
For h/d = 0,33, we get: Cpe10,A = +0,25
For zone B
We start on the same position on f/d axis, but this time, we reach the zone B diagram.
We read: Cpe10,B = -0,96
For zone C
We read: Cpe10,C = -0,40
In the end:
For zone A => Cpe10,A = +0,25
For zone B => Cpe10,B = -0,96
For zone C => Cpe10,C = -0,40
Starting from version 2021, vaulted roofs at the Eurocode 1 are covered by the climatic generator of Advance Design.
Wind actions, whether 2D or 3D, are instantly generated:
As prescribed in the Eurocde 1, roof is divided into 4 equal zones.
The name of each zone as well as their Cpe value can even be displayed with a dedicated annotation:
Conclusion
The evaluation of wind action on vaulted roofs by reading the graph from the Eurocode 1 can be tedious, with a high risk of error.
Fortunately, in Advance Design, this process is fully automated. Wind forces are created instantly, and they can be updated in a single click whenever a modification is made on the building.
The calculated structure can be synchronised with the Revit input model; to do this you export the model from Graitrec’s structural analysis software, Advance Design, using BIM Connect. Then select the synchronisation option in Revit and indicate the location of the exported file. The software generates a list of all elements, creating a breakdown of added, changed and deleted elements.
After reviewing the changes that have occurred in relation to the calculation, you can accept, ignore or remove the changes from the sync list. Once the changes are accepted, the model in Autodesk Revit will update.
In Revit, using the PowerPack Design module, it is also possible to design foundations together with the calculation of the reinforcement, based on given conditions. After the calculations, reinforcement drawings can be generated automatically. Most of the drawing’s components such as sections, their location, used labels, dimension lines or lists/bar schedules can be saved by the user in a template which is a native Revit file. From this, PowerPack will generate the drawings.
It remains to define the steel connections. This can be done directly in Revit or using Dynamo, but for the sake of shop drawings, it is suggested to export the model to Advance Steel. The connection calculations themselves can be carried out in Advance Design structural analysis software, using the Steel Connection Designer module.
Monolithic floor slabs are currently one of the most popular solutions. Depending on the structural system used, they can cover relatively large spans.
In most cases, the slabs are reinforced with a two-way orthogonal grid up and down. A common misconception among designers is that the determination of the cross-sectional area of this reinforcement for the ultimate limit state is based solely on the bending moments which are the same for the directions of the reinforcement. Thus the dimensioning of the reinforcement in direction “x” would be based on the bending moment Myy and the reinforcement “y” on the moment Mxx.
The example of a simple two-span slab, in which one span operates in a decidedly unidirectional manner and the other in a bidirectional manner, shows how to determine the authoritative, dimensioning moments. The loads and geometry are not particularly relevant. We will mainly discuss the nature of the plate work without attaching importance to values. The model and calculations were made with Graitec Advance Design.
It must be remembered that the orthogonal reinforcement grid results from a certain compromise between its optimality from the load-bearing point of view and the ease of subsequent execution on site. In reality the directions of the principal moments can be and in many places are deviated from the direction of the moment Mxx or Myy. Therefore, the most optimal reinforcement would be one designed according to the trajectory and based on the values of the principal moments M1 and M2.
Remember that the values of the principal moments must be interpreted with their directions, since they are not local or global values of the structure. Where the principal directions coincide with the directions of our reinforcement, i.e. x and y, this means that the dimensioning value of the bending moment will be the moments Mxx and Myy and the trajectory of this reinforcement is the best possible.
It is easy to see that the directions of the principal moments coincide with the x/y direction in the central bands, but deviate at the corners. Most designers who have ever dimensioned slab reinforcement in more sophisticated FEA-based software have probably noticed that the reinforcement map does not correlate directly with the maps of orthogonal bending moments in the local floor system.
The “butterfly” shape of the two-way free-supporting slab and the top reinforcement of the corners in both the X and Y directions are very characteristic. This is usually the most questionable aspect for designers – after all, the bending moment maps in no way correspond to this distribution of reinforcement – but it is perfectly normal behaviour.
The devil is in the torsional moment Mxy/Myx. Its presence is responsible for the deviation of the moments from the x/y direction. In the main directions we are only talking about the moment M1 and M2, there is of course no torsional moment there. If you decide to deviate from the main trajectory and reinforce the slab with orthogonal mesh, you must take this moment into account in the dimensioning of the reinforcement. The program Advance Design does this automatically of course by determining the relevant dimensioning moment at each grid point. In short, this means the projection of the principal moments onto the reinforcement directions.
Influence of dimensioning forces on the dimensioning of reinforced concrete
When dimensioning reinforced concrete members, the program determines the dimensioning forces which the user can display on the structure at any time.
Literature on the principles of reinforcement design for reinforced concrete slabs recommended the use of bottom diagonal reinforcement in the corners of free-supported slabs with a certain cross-sectional area (most often referred to as maximum span reinforcement in this literature). Designers usually use such reinforcement, but often without being aware of the design necessity. It is important to realize that the above-designed orthogonal X/Y reinforcement taking into account the torsional moment closes the topic and we are not required to use any additional reinforcement with a trajectory separate from the orthogonal reinforcement. The fact remains, however, that orthogonal reinforcement is not fully optimal.
To illustrate this phenomenon, it has been decided to model in the corner a slab whose local directions (and thus also the directions of the reinforcement in the adopted settings) are in accordance with the directions of the principal moments.
When using orthogonal reinforcement, both top and bottom reinforcement in both X/Y directions were required. For trajectory reinforcement, a bottom reinforcement perpendicular to the bisector and an upper reinforcement parallel to the bisector is sufficient. This means that the principal moments are at this point deviated by 45º from the X/Y direction.
One of the most time-consuming stages during the design of reinforced concrete structures is the calculation and generation of documentation for elements such as beams or reinforced concrete columns. And usually, it is not about the complexity of calculations or difficulties in generating drawings, but rather a large number of such elements in each project. And as in practice, we use dedicated software for designing, and it is mainly on the capabilities of this software and the ability to use it that the efficiency of work depends.
In this short article, we will address one of the key issues to reduce work time, namely creating and using design templates in design modules of Advance Design. The mechanisms described below are available in all design modules, including RC Beam, RC Column, RC Wall, RC Footing and Steel Connection module.
Creating project templates with Advance Design modules is very simple and consists in saving the current settings from the current project to a file. To start with, we perform a full design process of an element (for example the first beam in the project), and as a result, all the required settings are already defined and tested. Then we call the command to save the template and enter a name for the template file. From now on, the same settings as in the current project can be applied to other similar elements.
Saving the new template is possible when we run the module for dimensioning in the standalone version (image above) as well as from the menu in Advance Design (image below). In both cases, the template is saved to the selected location on disk as a file.
Thanks to the fact that template creation is based on saving settings of the current task we can easily add new templates in every stage of work.
Generally, it is a good idea to prepare one or more general templates. We set parameters that we always want to use in all projects, like settings related to design codes, general reinforcement settings, range of reinforcing bar diameters used, etc. These will be starter templates, primarily used for the first element in a given project.
Then, while working with a given new project, it is usually useful to prepare several current templates, specific for that project. These may be templates with different settings related to the location of the element in the building (then they differ in settings like concrete cover, fire conditions, etc.), or templates related to geometry (for example separate for edge beams, T-beams, etc.), or with different settings related to reinforcement design (for example with other methods of constructing transverse reinforcement). It all depends on us.
It is important that when saving the template, all information is stored, including project settings, geometry, design parameters, reinforcement parameters or list of load cases and combinations.
But even more interesting is the fact that in Advance Design modules, when applying templates, we can decide on the scope of data that is loaded from the template. That means that when creating a new task based on a template, we can easily choose what to load from the template. Let’s see a simple example. We have saved a template for a multi-span T-beam with specific reinforcement settings, with defined specific list of load combinations, etc.
Next, we want to use this template to design another beam, but this time it will be a single-span beam with a different list of load cases while keeping all the other settings. To do this, when creating a new job, we can deselect the geometry and load settings when selecting a template:
The above method is useful, especially when creating new elements / subsequent beams in the standalone version of the program, when we enter all the data ourselves, including loads.
The approach is slightly different if we base on the FE model prepared in Advance Design and perform calculations in the design modules directly in Advance Design, or if we perform design calculations in stand-alone modules after exporting the element data to files. In this case, we are not defining the element from scratch because we already have the element with a defined geometry and internal forces, but we want to use our own templates to set all other parameters of the element. To do so, the template must be assigned to the element in Advance Design before sending it to the dimensioning module. This selection is made from the element properties in Advance Design.
Remember that the list of available templates then shows the names of template files located in the corresponding subdirectory on disk, which is different for each element category (beams, columns, walls, foundations or steel connections). All of these subdirectories are grouped into one master template directory in the User Folders of Advance Design’s design modules. The location of these directories is visible, for example, when saving templates.
So if you want to use different ranges of templates for different projects, it’s most convenient to simply archive/copy individual subdirectories or the entire main element template directory.
Of course, the use of project templates is basic but not the only way to increase the efficiency of the design process. Another way is to use your own drawing templates used by the Advance Design modules so that the time spent preparing and adjusting the reinforcement drawings is greatly reduced.
Another way is to optimize the workflow – for example, we can easily export the data for the design of reinforced concrete elements from Advance Design to files, separately for each element, and then distribute them to the individual team members. Then they can carry out the design and documentation process in parallel on separate computers using the stand-alone versions of the modules. In addition, the reinforcement files can be copied back into the project structure in Advance Design.
As well as calculating linear and non-linear statics, Advance Design can also perform what is commonly known as a buckling analysis. Buckling is the loss of stability of an element under axial compression force. As long as this force does not reach a certain critical value, the element will only shorten. Beyond this critical value, the element is thrown out of equilibrium, which is also called buckling. A structure can only be said to be stable if it can return to its original form after being tilted out of equilibrium.
The phenomenon of loss of stability in general is a rather complex issue. The linear buckling analysis itself, however, is quite easy to set up and carry out. It involves solving an eigenproblem that results in eigenvalues and eigenmodes. We will call the eigenvalue the critical multiplier and the eigenmodes simply the stability loss form. The force in an element multiplied by the critical multiplier is the critical force at which the element loses stability.
In simple cases (e.g. isolated elements), the critical force may be determined from Euler’s formula:
The designer must instead estimate the buckling length of the member, which is sometimes relatively easy. The forms of loss of stability and the buckling length for simple static schemes are generally known and are presented, for example, in EN 1992-1-1.
The problem starts to arise with unusually braced structures, where it is not so easy to estimate the rotational stiffness of the nodes. By solving a linear buckling analysis, it is possible to know the critical force and thus the buckling length.
Linear buckling analysis
The buckling analysis gives an answer to how close an element/structure is to losing its equilibrium state. If the critical factor is less than 1 (i.e. the load would have to be less than that currently occurring) the structure can practically be excluded from further calculations. The value of this multiplier if it is greater than 1 will give us information how sensitive the structure may be tosecond order effects and imperfections. This is mentioned in clause 5.2.1(3) of EN 1993-1-1, where it allows the use of 1st order analysis in calculations, provided that αcr > 10.
For a simple example of a cantilevered steel column (IPE400) 8.00m high loaded with a unit axial force, the results of the buckling analysis are presented below.
The first two forms of buckling are in the direction of the weaker axis of the section, the third in the stronger axis. The smallest critical factor is 106.68, assuming that the force was unit. That is, if the axial force was 106.68kN the column would buckle. Looking at the form of the loss of stability in each plane it is easy to see that the buckling length is 2*L – you can also ask the software for this figure – for evidence it will be determined using Euler’s formula.
An analogous check can be made in the second plane, the lowest coefficient of which corresponds to the third form of loss of stability. For a classic cantilever in both planes, 16.0m is expected in this case.
As you can see, buckling analysis is easy to carry out and accurate in simple cases. The case shown is as simple as possible, where the bar is subjected to axial, ideal compression.
The important thing to remember is that simple buckling analysis is fully linear – that is, both geometrically and material-wise. It is a very fast tool giving an answer in a short time about the potential behaviour of the structure, but it does not take into account 2nd order effects, and the material works elastically throughout.
In a situation where the whole structural system is analysed, and not just a separate element, the matter is somewhat more complicated – the critical factor, closely related to the form of loss of stability, should be identified with the elements that lose stability in this form. For a simple frame, analysed only in the plane of the system, 20 successive forms of loss of stability were obtained. The axial forces are shown below (only in members that are in compression, assuming that they do not lose stability in tension).
As shown in the image below, the 1st form of loss of stability is a global, canted form. The frame columns clearly lose stability in this form – the critical multiplier is 356.19, so with an axial force of 10.16kN, the critical force is 3618.89kN. Each subsequent form is responsible for the loss of stability of the compressed upper chord and the compressed posts and diagonals of the truss. The multiplication factors of these forms cannot, of course, be taken into account for the determination of the critical force and buckling length of the columns for example. Members that were not in compression in the buckling case do not lose stability.
Advance Design 2021.1 Update is enhanced with new functionalities and improvements with high benefits for the end-user. It is articulated around a few main subjects:
Modelling and workflow enhancements
New options and improvements to the Steel design
New options and improvements to the Concrete design
Improvements to concrete and steel Design modules (previously known as BIM Designers modules)
Among many new functionalities and improvements, we would like to highlight:
Exchange of load combination definitions with Excel allows easy management of load combination definitions by using new Export and Import
Improvements to the transfer of loads to Design modules allows easy transfer of the list of definitions of load combinations to design modules.
Increased performance of Design modules significant increase in work comfort, especially thanks to the substantial reducing the time of generation of drawings.
RC calculations for concrete beams defined as super elements allow the design of multiple span beams having different height and support widths as a single element.
Interactive drawings for steel connections easy and full control over the content of the drawing thanks to the ability to freely compose drawings, easy modification of the location of drawing components, and scale for views.
Update 1 to Advance Design 2021 also comes with many other improvements and adjustments following the feedback received from thousands of users worldwide. It brings also a big number of corrections of known problems and also includes all the fixes and improvements made with the previously released Hotfix 1 (2021.0.1) and Hotfix 2 (2021.0.2).
We are inviting you to take a quick look at the selected improvements brought to the Advance Design 2021.1 Update.
Modelling and workflow enhancements
Advance Design 2021.1 comes with several new features and improvements dedicated to the modelling and workflow.
Exchange of load combination definitions with Excel
Thanks to new Export to Excel and Import from Excel commands we can easily manage load combination definitions by using Microsoft Excel spreadsheets.
Pushover: Displaying a report with status only for selected plastic hinges
When analyzing the results of the pushover analysis by using report tables with the status of plastic hinges, the content of these tables is now filtered to the current selection of elements in the model. It greatly facilitates viewing the results, as we can focus on the statuses of plastic hinges from selected elements only.
Simultaneous creation of holes for many surface elements
When creating holes in surface elements, it is now possible to create a hole in multiple elements simultaneously on the basis of a polyline cutting through several contours.
Shortcut to the Section Editor directly on the ribbon
To facilitate and speed up the opening of the module for creating and editing cross-sections, an icon with the command to open the module directly has been added to the Manager ribbon.
Thickness in tooltips
The Thickness property has been added to the list of available attributes to be selected for the content of tooltips.
System names on the color legend
When displaying a color legend for elements colored by systems, in addition to system ID the name of systems is now displayed. It greatly facilitates the identification and improves the quality of the created documentation.
Improvements to the transfer of loads to Design modules
To improve the transfer of load-related information when transferring data from the Advance Design model to the design modules, new options have been added to easily transfer the list of self-created or modified definitions of load combinations to design modules.
New possibilities for Steel Design
Advance Design 2021.1 comes with several new powerful features dedicated to the design of steel structures.
The new version of the Canadian code for the steel design – CSA S16-19
Since version AD 2021.1 it is possible to perform design calculations of steel linear elements using the current version of the Canadian CSA standard: CSA S16-19.
Update of the Canadian CISC 11 steel section database
Steel profiles from the CISC 11 catalogue (the 11th CISC handbook) have been updated. The changes mainly concerned with changes in naming, adding missing profiles to catalogues and slight changes in the values of the characteristics for a few selected profiles.
Improvements to displaying results of the steel design
A number of improving changes have been made to the presentation of design results of steel elements (according to Eurocode 3) in the Shape Sheet window and related reports. These changes increase the readability of the results as well as allow for a more detailed verification of the results. The most important of these are:
Uniform rules for the presentation of results for individual strength checks.
The cross-section class is now displayed for each check separately, determined on the point where the check was done.
Replacing the oblique bending check by bending with an axial force, bending with shear forces, and biaxial bending checks.
Imperfections on steel columns defined as superelement
Steel columns defined as superelements can be used for the automatic generation of imperfections (according to Eurocode 3). During the generation of forces, the user can decide whether to consider the elements that intersect the superelement.
Improvement in the creation of generic steel joints
To facilitate and speed up the definition of generic joints for steel elements, the command to create them based on the current selection of steel elements has been added. A new command is available on the right-click menu and creates a single connection for steel elements that are in contact at the same point.
New possibilities for Concrete Design
Advance Design 2021.1 also comes with several improvements dedicated to the design of Reinforced Concrete structures.
The new version of the Canadian code for the concrete design – CSA 23.3-19.
With the Advance Design 2021.1 Update it is possible to perform dimensioning calculations of concrete linear and planar elements using the current version of the Canadian CSA standard: CSA 23.3-19.
Superelement for RC beams
The super element concept is now applied to the concrete linear elements for the reinforcement design according to Eurocode. This gives a possibility for the design of multiple span beams having different height and support widths as a single element
Extension of the list of rebar diameters for Poland
In order to enable the calculation of the real reinforcement with the use of reinforcement diameters used on the Polish market, new diameters (18, 22, 28, and 35) have been added to the list of reinforcement bar diameters available on the reinforcement settings window. This change is available for projects having the localization set to Poland.
Improvements to Design modules
In the latest version of the Advance Design, many improvements have been introduced to the Design modules.
Unification of brand names
In the current 2021.1 version, further changes have been made to unify Graitec software brand names. Accordingly, the design modules previously named Advance BIM Designers are now called as design modules of Advance Design.
Speed improvement
One of the most important changes introduced with this update of design modules is the increase in performance. Thanks to optimization in many areas, there are significantly reduced times of starting modules, loading projects, calculations and, above all, generation of drawings.
Improvements to the info panel
The info panel content for the RC modules has been supplemented with additional types of results, including: minimal reinforcement areas for beams, more details for top longitudinal reinforcement on beams, buckling information for columns and punching verification for foundations.
Slovakia localization
The Slovakia localization is now available for design modules, which allows for running the design calculations according to Slovak appendixes to Eurocode.
The new layout of the Reinforcement Assumption dialog windows
The layout of the Reinforcement Assumption dialog windows has been updated for the RC Column, RC Wall and Footing modules. As with most other windows with a new layout (tree menu on the left, parameter fields in the central part, and explanatory drawings on the right), the definition and change of parameters are much easier and faster.
Improvements to views
A number of improvements have been made to the graphical presentation of the RC views, including a possibility for hiding a formwork from 3D views, a possibility for changing a render mode, a possibility for filtering of the displayed loads and a new mechanism for displaying loads on RC beams.
Interactive drawings for steel connections
Drawings generated by the Steel Connection module are now managed by the interactive drawing mechanism, similar to other RC modules. Thank to this the user has control over the composition and all drawing elements.
Double Angle section for diagonals for Gusset Joints
The 2021.1 update of Advance Design Steel Connection offers a new configuration for the Gusset Joint – the double angle section for one, two or three diagonals
Learn more about Advance Design Update 2021.1 from our dedicated webinar!
Learn about Advance Design and visit our Virtual Stand! All the necessary information gathered in one place, all to make access to information about our software much easier!
An important advantage of the innovating multi-platform Advance BIM Designers collection of apps that allow automatic generation of 3D reinforcement for reinforced concrete elements is the possibility of direct integration into the interface of the Advance Design calculation software.
One of the many benefits of this integration is a more efficient footing presizing process, after the structure is modelled and a FEM analysis is performed directly in Advance Design.
Advance BIM Designers reuses all information related to material, size or forces in a support and automatically generates reinforcement cages, drawings and reports, based on user-defined reinforcement assumptions.
We are pleased to announce the release of Service Pack 1 forGRAITEC Advance Design 2016!
ADVANCE Design 2016 SP1 offers more than 140 improvements and corrections. The main new features in this release are the the moving loads generator (that enables the user to create traffic loads on road bridges according to EN1991-2 – Section 4) and a new cross section library for Precast Concrete BridgeBeams, please see the relevant videos on these below:
Customer Project: Goodwood Festival of Speed 2015 – Mazda
Software used:Advance Design Project location: Goodwood House, Chichester, UK Artist: Gerry Judah Architects and Engineering: CAPITA P & I Client: Goodwood Festival of Speed 2015
Project description:
Each year, the centrepiece lawn in front of the main Goodwood House showcases a breath-taking sculpture for the annual Goodwood car show, designed by Gerry Judah, Architecture and Engineering by CAPITA P&I and Fabrication by Littlehampton Welding Ltd.
Hooman Baghi, Principal Structure Engineer:“Using Advance Design enabled us to import the model geometry using BIM swiftly and smoothly. Loads and combinations were assessed making easy dynamic analysis of this complex model. “
GRAITEC announces the User Meeting organized by its Czech subsidiary on December 11th, for the Advance users from Czech Republic, Slovak Republic, Serbia, Croatia and Slovenia. The meeting will take place at hotel VIVALDI, Jihlava, Czech Republic.
The purpose of this meeting is to present customers with the new functionalities and improvements of Advance Steel, Advance Concrete, Advance Design and other Graitec products. And most importantly, to demonstrate the concept of BIM data exchange between architecture, steel and concrete structures and MEP.
Throughout the meeting, customers will be able to consult with our experts regarding the future of all products, and even find out about our current special offers.
More than 500 Advance customers were invited to this event and an online version of the meeting will be available, for anyone that cannot attend.
Prior registration is not required.
The itinerary for the meeting will be as followed:
GRAITEC, European BIM software developer for the construction industry, announces the release of Advance Design 2015 dedicated to structural engineering.
Advance Design® is specifically dedicated to structural engineers who require a professional and easy-to-use BIM solution for structural FEM simulation and optimization according to specific design standards (Concrete, Steel or Wood).
Advance Design 2015 is articulated around 3 main subjects:
Concrete deflection calculation: new options for the reinforced concrete design according EC2
New starting screen for easier use
The implementation of the new NTC2008 Italian codes
When designing a reinforced concrete structure, engineers must check limit deflections, especially on beams and floors. This is achieved by taking into account the cracked inertia of the reinforced concrete section. However, in FEM calculation, this leads to specific modelling and iterative processes which are tedious and time-consuming tasks for engineers.
Advance Design 2015 now automatically performs concrete deflection calculation based on theoretical or real reinforcement computed by the software.
Process: Successive design steps are performed, with concrete inertia being automatically calculated at each iteration. Concrete inertia is actually given by interpolation between a fully cracked state and a non-cracked state, in accordance with article 7.4.3 from EN1992-1-1.
Graphical results and reports allow for a quick and easy post-processing of all intermediate values: cracked inertia, non-cracked inertia, interpolated value, deflection for each mesh…
ADVANCE DESIGN 2015: New starting screen for easier use
In order to simplify (for the new users) the first steps with Advance Design, the 2015 release comes with a brand-new starting wizard from where the user can access many types of information:
Several project samples for each type of structure: the user can open the models he is interested in to see how to model, define the main assumption, assign design templates…
Several other help tools are available: online videos, Graitec Web pages, quick access to the documentation, software configuration… All those tools are specific to each country, depending on the configuration settings.
ADVANCE DESIGN 2015: entering the Italian market
Advance Design 2015 now features the NTC 2008 Italian codes for:
Actions combinations automatic generation
Seismic loads
Climatic loads (Wind & Snow)
Reinforced concrete design
Steel members design.
ADVANCE DESIGN 2015: and also…
The 2015 version brings a number of new features and adjustments based on feedback from thousands of users:
New solver option for improved torsor calculation on walls using T6-Q9 elements
Uniform diagrams for linear support actions for easier post-processing
Improved export of a meshed model through a .TXT file format
Update of the SRSS modal summation method for faster seismical analysis on simple models.
Advance Design 2015 is part of the GRAITEC Advance 2015 Suite that also consists of GRAITEC Advance BIM Connect 2015 and Advance CAD 2015.
GRAITEC BIM Connect 2015 allows sharing and synchronization with Autodesk Revit® 2015 models.
Advance CAD 2015 is a 2D / 3D CAD software that enables engineers and detailers to modify or create DWG drawings. The 2015 version brings many functional enhancements such as new toolboxes, angular dimensions on dynamic blocks, new dimension styles… as well as improved performance.
Advance Design 2015 now features the NTC 2008 Italian codes for: