Graitec PowerPack propose a specific command for assigning reinforcement to a layer (for example Top or Bottom) for easy and quick filtering of the reinforcement.
The layer might refer to a geometrical location of reinforcement but also to another purpose, such as its function.
The information about the assigned layer is stored using shared parameters: G.Rebar Location for Structural Reinforcement and G.Fabric Location for Structural Fabric Reinforcement.
The assignment is done automatically and manually. The automatic method is applied during reinforcement generation using calculation modules or reinforcement generators in PowerPack. For example, the top bars in the foundation have an automatically assigned value T (a default name for a top reinforcement). This automatic assignment is made to the selected rebars, for example in the case of a foundation to the lower and upper bars in the pad.
The manual assignment is done for selected reinforcement using the Assign Layers command, which is available in the PowerPack Detailing ribbon.
The Assign Layers command opens a special dialog with the list of default/predefined layers.
The content of the list is based on the configuration from the Reinforcement Layers Definition window, opened by the Layers Definition command. The user can modify names for default layers, use the Active option to limit the list of layers that can be available during the assignment and add new positions/layers to the Other group.
The value of the layer parameter is mainly used in the new options of the tools for controlling the reinforcement visibility. Indeed, to the Rebar Visibility functionality, a new group of options for selecting by layers is added.
When the Top or Bottom option is selected, then an additional filtering for reinforcement is activated, respectively by the top and interior or the bottom and exterior layers. When the Selected option is active then the selection of layers for displaying is done through the dialog opened by the Select Layers button.
In addition, three commands are available under the drop-down list under the Rebar Visibility: By layer, Hide All Reinforcement and Show All reinforcement.
Hide All Reinforcement and Show All Reinforcement allow you to quickly turn off or on the visibility of the entire reinforcement in a given view. By Layer allow you to quickly select the reinforcement to be displayed by using the Layer property.
This is particularly useful when generating drawings with separate views, e.g. for bottom/ top reinforcement for slabs or foundations.
Article by Stevens Chemise / BIM Industry Manager / GRAITEC France
During the last few years, the Advance Design reinforced concrete modules have been progressively getting more and more configurable for automatically generated reinforcement. New customer-specific settings are added in each version, making the modules for RC beams, RC columns, RC foundations as well as RC walls and RC slabs more and more configurable. This allows you to set the parameters in such a way that the reinforcement for the elements is generated according to your expectations. And of course the expectations on the reinforcement of an element can be different, depending on the user and sometimes on current needs. Sometimes in one project the focus is on the optimum use of the reinforcement and in another on the ease and speed of construction.
Today, let’s look at a few selected reinforcement settings for reinforced concrete beams.
Common longitudinal reinforcement for the spans
Imagine that we have a reinforced concrete beam with several spans. We have modeled and calculated it as a continuous beam, and we want to generate the longitudinal reinforcement for each span separately. This is the default setting of the module.
But if we want to get the effect of continuous longitudinal reinforcement on all spans we can get it very simply. In the window Reinforcement Assumption on the Longitudinal Bars tab we have dedicated options ‘Bars on Multiple Spans’.
The option Top/Bottom bars extend across the entire beam can be enabled independently for longitudinal bottom and top reinforcement. Additionally, you can select whether you want to extend bars from the first layer only or also bars from all layers (if any).
Let’s take a look at the examples in the pictures below (only the main bars of the bottom reinforcement are shown for easier understanding).
Linking of longitudinal members with transverse reinforcement
One of the settings for transverse reinforcement is the default shape type of these bars. In the Reinforcement Assumptions window on the Transversal Bars tab, we have a number of useful options for setting shapes. One of them is the possibility of deactivating the automatic selection of shape types and the possibility to choose from the list the type of transversal reinforcement – and actually the way of joining the longitudinal bars not located in the cross-section corners. We have 4 types available, as on the pictures below: A – None, B – Stirrups, C – Pins and D – Multiple links.
Note that multiple links for this case can have two solutions: with one large and one small stirrup or two identical ones. When we can have more longitudinal bars in a layer (than 4, as is the case on the above picture), the number of possible configurations for multiple links is larger. This can also be set according to our needs in the Multiple Links tab where we can graphically choose default settings for different number of longitudinal bars.
Maximum number of longitudinal bars
One of the reinforcement settings is the number of members of the longitudinal reinforcement to be generated due to the width of the beam cross-section.
These settings are available in the Reinforcement Assumption window on the Numbers of bars tab. We can set there the number of longitudinal bars in the span and in the support for different width ranges of the cross-section.
So for example if the cross-section is 300 mm wide, 4 longitudinal bars (in the span and in the support) are taken automatically. Depending on the required calculated theoretical reinforcement, the program will then select the diameters of these bars and if necessary, add additional layers of bars. But among the options available in this configuration window we can also find a special option that changes the way of determining the number of longitudinal bars. It is called Consider number of bars and layers as maximum limits. When this option is not active, the entered number of bars is considered as imposed. When this option is active, then the number of bars is considered as maximum allowed value and the number of bars will be automatically determined based on required reinforcement area.
As the selection of this method for a given required reinforcement area can lead to a variety of possible solutions, e.g. fewer members with larger diameter or more members with smaller diameter, two options are additionally available for choosing the preferred solution:
Smallest reinforcement area – will assure the smallest difference between the real and the theoretical reinforcement area.
Minimum number of bars – will assure the minimum number of longitudinal bars and will eventually lead to bigger diameters.
Typically, both options produce fewer bars than the fixed number of columns method, especially when the second option is chosen, but the end result also depends heavily on other assumptions. We can see a simple example for a cross section having 300 mm with three different settings used: A – the number of columns of bars is fixed (which gives 4 columns of bars for this width), B – the number of columns of bars is a maximum limit, and the first option “Smallest reinforcement area” is selected, C – as previously but the second option “Minimum number of bars” is selected.
All these settings give different configurations for the number and diameters of longitudinal members, but they all satisfy the section verification requirements and give a larger area of real reinforcement than the required area of theoretical reinforcement.
The above settings are only a fragment of the possible settings. It’s worth to get to know all the settings, because thanks to the multitude of configuration options and the possibility to save them to templates, using design modules of Advance Design we can dramatically accelerate the daily work.
Article by Mateusz Budzinski / Technical Product Manager / GRAITEC
Recently introduced into the Graitec Stairs and Railings, deployed as part of the PowerPack for Advance Steel, is the New Lug feature for Railings. This new feature allows user to split up the infill panels for site installation, making it easier to transport and install these items if difficult site workspaces, I speak from experience here when trying to transport and install Railings with solid bar infills, can be quite a challenge in the confined space of a Stairwell.
Behind this new feature there are essential settings that can allow the user different types of configurations for the user to allow for combinations needed for full and partial assembly.
Basics of Railings Lug Activation.
The railing lug option inside the Railing macro is available working with mid-rails to post connections, it is available under the Handrailing Connection Tab, as a sub tab Fixing lugs.
Important Setting 1
When you first go to the Fixing lugs tab you may see a dialog page that has a warning message about the availability of the lugs, this is default settings that is driven by the settings under the Middle Handrail to post Tab
The message shown above is driven by the setting in the Middle handrail to post, from the General Tab Connection properties, connection type, the combo box must be set to Aligned.
Setting this and returning to the Fixing lugs, the user will then see the option to activate lugs for all or each post location.
On the Fixing lug page, the user will start with a combo box set to ‘ No Lugs’, changing this drop down will enable the fixing lugs, noting that the user has a choice to select which method of lugs they wish to use.
When selected the lugs are then active and the user can start changing the lugs arrangements.
Important setting 2
So, the user has set the lugs to horizontal, this means the lugs are positioned along the adjoining mid rail. But when we set the mid rail Connection type to aligned, then the user must look down in that dialogto change the Check box for the ‘Use Bevel cut on Slope’, unchecking this box will make the mid rail ends change to a square cut end.
Unchecking the box will change the mid-rail ends as shown in in the next image
Lug Types (tip for full vertical closure type)
We saw in the initial drop down that the user can have both horizontal and vertical lugs, but there is another variation under Vertical type, that is a Full Vertical type. This type can be used to create an end closure to a railing panel that is bolting through and adjacent post. Useful for when railing panels are too long and need splitting into manageable sections for installation.
The user can change the basic lug type to Vertical from the initial combo box, see top of the dialog tab. Then using the Type combo box, the user will see options for ‘Each middle rail’or ‘Full Height’, Changing to full height will place a continuous vertical section at the panel end or start depending upon the location settings.
Also another nice feature of the Graitec Macro, is the dialog Tree Structure that allows the user to set the same parameters and types for all the posts in the railing panel, or for each posts, note the structure in the dialog and see that in this instance we have chosen to select Post 2 location, as we wish to split the Top rail at this location also. (split top rail is feature of the Graitec Railings.)
When this is applied you can also go back and change the mid rail ends to give a sloping cut and if required to vertical Flat Section, noting that we changed from Plate to Rolled Steel flat bar section, same as the handrail profile (Could also be different if required.)
There are many other features of the Graitec Railings macro that allow users to progress their designs efficiently and quickly and store settings that they commonly reuse within the product ranges.
Look out for more Tips of using the Graitec Railing tools in our blogs and Video postings.
Revit propose a various set of commands to distribute rebar within a structural host. It is also possible with Revit native tools to distribute a specific rebar shape along a path with the Path reinforcement command.
This workflow could be used for any polyline path globally.
Nevertheless, in term of possibilities, this tool is not allowing the placement of rebar parallel to the major path such as longitudinal rebar. Graitec PowerPack is proposing a dedicated command to speed up the process of placing a set of bars along a path.
The Edge Reinforcement command is used to quickly generate structural reinforcement along the edges of elements such as slabs or walls. It is available on the PowerPack Detailing ribbon:
This command works by selecting one (or more) edge face, so that the reinforcement can be generated for multiple configurations.
The configuration window allows the setting of parameters for:
transverse reinforcement (open or closed)
and longitudinal bars, separately for vertical, top and bottom distributions.
The available settings allow for many different layout configurations, for example:
With version 2022 of Advance Design, a module for the generation of the real reinforcement for concrete slabs has been introduced. One of the main tasks of this module is to prepare the reinforcement cage on the basis of the previously calculated theoretical reinforcement and then to prepare a drawing with the description of this reinforcement.
In practice, the theoretical reinforcement is calculated on the basis of the results of the FEM (finite element) model. However, the FEM calculation model itself, by its nature, is usually a simplification of the real geometry of the structure.
But for the real reinforcement and the drawing documentation we have to take into account the real geometry of slabs and supporting elements like beams, columns and walls. Of course, the extent to which the calculated and real models diverge depends on how the FEM model was created. So, how can we ensure that the real reinforcement and the drawings correct in case of model differences? Let’s take a closer look at the possibilities the new module for reinforced concrete slabs in Advance Design offers in this respect.
Consider the first case – the position of the axes of the supporting elements (beams, columns and walls) in the FEM model is consistent with their real position, while the outline of the slab is simplified – the edges of the slab are modelled along the outline of the support axis. This is a common case, especially when the model has been created based on construction axes.
After importing the slab model into the RC design slab module we’ll see the outlines of the supporting elements and the edges of the analytical slab model (green lines in the images below). While the analytical model cannot be modified at this point, we can automatically modify the external geometric contour of the slab. In this case, we can automatically adjust the geometric contour of the slab using the option available in the geometry parameters window called ‘Slab physical contour’.
With this option we can decide whether: ->leave the geometric contour unchanged, as identical to the analytical contour;
-> extend the geometric contour to the outer contours of beams and walls;
-> extend the geometric contour to the outer contours of the columns;
-> extend the geometric contour to the outer contours of any supports (beams, walls and columns). For this corner example, the effect of this last option is the same as for the previous one.
Note that the change concerns the geometric contour of the plate, while the analytical contour remains unchanged. Therefore the values of the determined theoretical reinforcement do not change and the generated real reinforcement in the stretched area of the slab is assumed to be the same as on the edge of the analytical contour.
Let us now consider a different case – the position of the support elements in the FEM model is different from the real one. To illustrate this we will use the same corner from the model shown above. Let us therefore assume that in reality the column is aligned with the correctly modelled beams.
In this case we can use a graphical method to edit the geometric model. To do this, we select the appropriate icon and choose graphically the element that we want to modify.
The new position of the axis is then indicated graphically or the value of the displacement vector is entered from the keyboard.
In a similar way, we can move beams and walls. In addition, it is also possible to graphically modify the position of individual edges of the geometric model of the slab.
Of course, when the geometrical contour of the slab is changed, this affects the arrangement of the reinforcement bars, including their number and length. On the other hand, when the position of the supports is modified, in most cases only the reinforcement drawing is influenced.
Thanks to these easy-to-use methods of geometry modification, the final effect, i.e. automatically generated drawing, corresponds with the real geometry of the slab.
Revit propose a process to create reinforcement for most structural members, based mainly on two steps: first place the rebar shape in an appropriate section view and then distribute it in an elevation or the opposite, place the rebar shape in an elevation and then distribute it in a section (for longitudinal bars for example).
This manual and repetitive process therefore involve multiple manipulations and frequent switching between Revit views.
Whether for slabs or walls, the reinforcement of any kinds of openings is a recurring operation during projects. This technical aspect is addressed by one of the functions of the Graitec PowerPack, Reinforcement Openings.
This Openings command is used to quickly generate constructive reinforcement around openings. It is available on the PowerPack Detailing ribbon.
The command enables the generation of reinforcement around openings on slabs and walls. It allows as well rebars generation for multiple separate openings at once. For a selected opening , it opens the configuration window with parameters related to concrete cover and tabs for different reinforcement bar types.
The Cover section allows the manual control of the cover, the automatic cutting of bars in case of holes close to the edge and the option to automatically adjust the cover to the existing reinforcement, to keep the correct 3D arrangement of bars.
The remaining parameters are available on independent tabs separately for four optional reinforcement types: Main bars (longitudinal bars along edges), Diagonal bars (bars that are perpendicular to bisectors of corners), Edge bars (transverse bars along edges) and Lintel bars (longitudinal and transversal bars above openings on walls). Thanks to the wide range of settings, many different bar configurations are possible.
This new version 2022 has added a special option of opening rebar for door by the possibility to add or not the bottom diagonal rebar.
In the case of non-rectangular shapes of openings, the reinforcement is generated on its rectangular external perimeter
For beams, users may have to deal with several situations with openings such as placed within the beam, a depression … For all those situation, Graitec PowerPack provide some dedicated tools.
Firstly, the command Main bars or Constructive Dispositions can generate a 3D rebar cage on beam, even those one with custom shape including openings and depressions.
Then, it is also possible to add reinforcement around an opening in a beam with a dedicated command. This opening could be created by the native command By face.
All connections available in the Steel Connection module can be designed using all combinations or envelopes created from those combinations.
The possibility to choose how to use the combinations in the design process is available in the Design Assumptions dialog.
By selectingEnvelopes method, the calculation will be performed using only the combinations that provide Max/Min of the design forces using certain filtering criteria done in Advance Design Steel connection.
The envelopes that are considered now in calculation can be seen inside the new Combinations report or inside detailed or intermediate reports in the Load combinations chapter.
The Combinations report added to the available report list for each joint type will display only theLoad combinations description chapter, which will provide an easier and faster way to access the envelope list.
As have been mentioned, there are two options possible: All and Envelopes.
Now let’s see how the selection affects the behavior during calculation process.
Combinations = All
For Combinations set on “All”, the Advance Design Steel Connection is using all the combinations generated to design the connection.
For the Base Plate connection for a tubular column as on the picture below, the number of combinations is 181, and all are used for design calculations. It influences the report (as a table listing all the combinations is long), but the most important is that due to the number of combinations, the calculation time is relatively long.
Combinations = Envelopes
For Combinations set as “Envelopes” the module will calculate the connection using just some of the combinations which are fulfilling certain criteria.
The criteria used to select just a part of the combinations are the following:
Based on these criteria, Advance Design Steel Connection module is selecting the combinations that compliant with one or more criteria and does the design calculations based on the selected combinations.
The calculation time decreases, and the report is much more compact as only the selected combinations will be listed.
For the Base Plate connection for a tubular column as on the picture below (having more load cases that the previous example), the number of combinations is 482. But this time calculations are done with “Envelopes” of combinations.
Even there are 482 combinations, thanks to the envelopes, the calculation time is less than for the previous example. And in addition, the report does not have pages full of combination tables and it is generated much faster. The Load combinations description table on the report contains now only several combinations that are fulfilling one or more criteria. And the connection is verified using these combinations
As the 2022 version of GRAITEC Advance Design introduced the Crane Moving Loads feature, in this short article we will take a look at the moving loads available in Advance Design – the Traffic load and the new Crane load. As the traffic load generator has been available for a long time, I will present only brief information about it and focus mainly on crane loads.
Let us start with the traffic load. The traffic load generator enables us to create traffic loads on road bridges according to EN1991-2 (Section 4). In order to create the appropriate traffic loads on the road bridge (on planar elements), we define graphically the elements composing the carriageway: one or several traffic lanes, remaining areas and footways or cycle-tracks.
The next step is to add a Traffic loads family and select the appropriate load model, according to the provisions of the Eurocode. Five load groups are available, containing respectively:
gr1a – combination of the concentrated loads (Tandem Systems) and the Uniformly Distributed Load (UDL System) with the uniformly distributed load on footways.
gr1b – a couple of concentrated loads that represent a single axle of a truck, for creating concentrated forces along the lane.
gr2 – combination of the concentrated loads (Tandem Systems) and the Uniformly Distributed Load (UDL System) with braking and acceleration forces and centrifugal forces.
gr3 – uniformly distributed load on footways.
gr4 – uniformly distributed load on footways and traffic panels.
After automatically assigning the load parameters to the roadway, we are ready for load generation in the model.
Depending on the load model selected, this results in load cases that include uniform loads as well as a series of consecutive steps in the position of the concentrated forces from the vehicle wheels.
For loads from cranes, the process is somewhat similar. The first stage consists in defining graphically the route of the crane forces – it can be a single polyline to model the forces moving along a single rail (for monorail crane modelling) or two parallel lines to model the route for the forces from two trucks on both sides of the bridge crane.
The next step is to add a Crane object. It is used to describe the geometry, such as the number and spacing of the wheels, and to describe the forces from the wheels.
In the simplest case, the forces on each wheel can be defined manually, separately for each wheel. But it is also possible to use three different automatic methods, so that the wheel forces are automatically determined according to the rules of the standard.
We have three methods available for the automatic determination of forces:
By crane loads(EN 1991-3) – for defining wheel loads automatically on the basis of entered crane loads, by using Eurocode EN 1991-3 rules. In this method several loads of different origin (e.g. loads from crane self-weight, from the weight of the load, from braking forces, etc.) are separately entered for each wheel. These load components are combined with the dynamic factors and the final wheel forces are determined. As the result this method gives several groups of load sets (ULS Group 1 to 6), according to the EN 1991-3.
By crane parameters (EN 1991-3) – for defining wheel load automatically on the basis of entered crane parameters, by using the Eurocode EN 1991-3 rules. The main difference compared to the previous method is that the values for each wheel are not entered, but the crane parameters (like self-weight of the bridge, self-weight of the trolley and the crane capacity) are given. The output is the same as for the previous method – six groups with sets of forces for each wheel.
By crane parameters (ASCE/NBCC) – similar to the previous one, so we do not enter the forces on individual wheels, but such loads are calculated automatically on the basis of entered crane parameters. But this time the method of automatic load generation is based on the general method, related to US/CAN standards (especially ASCE). But it is worth to mention, that the load generation rules are generic and are essentially independent of any standard.
With the crane runway and the crane with the forces on the wheel, we can proceed to the next step, which is the definition of the load family. Here we determine the range of crane movement and the number/length of moving load steps.
The generation of crane moving cases is done automatically after using a ‘Generate’ command available when right click on the Crane Load case family. After it is run a set of moving load cases are generated, separately for each crane and each step position. They contain the forces from all wheels in a given position. Depending on the definition of the crane, these are both vertical forces and horizontal transverse or longitudinal (from braking) forces.
Together with the load case generation, sets of force envelopes from all force positions are also generated.
Importantly, we can define more than one crane and place them on the same or different runways. In this case, the program will generate for each crane a series of all force positions and then, when the envelope is generated, only the possible combinations of crane positions are considered.
The final load combinations are defied by using typical load cases (dead, live, wind…) and Crane Envelopes. This is particularly important when there are a large number of crane steps and especially many cranes, as the final combinations consider only a dozen or so envelopes instead of thousands of crane position combinations.
The static calculation and the results for the combination cases do not differ from other load types and you can check the results for each crane position as well as for the envelope of the crane forces. Specific to crane is a new type of graphical output – the influence line diagram. It shows graphically the value of the result at a given point for all successive positions of the crane. Although in this version of the program the influence line diagram can only be displayed for displacements in structure nodes, it is one of the additional tools useful when analyzing the results.
June 1st we released our products for their 2022 versions, this covers the entire Graitec portfolio, well within that there are few things that stand out to me coming from the Steel detailing and design background, that sound a clear intention of Graitec in this area.
The first one is within our analysis engine ‘Advance Design’, the New feature of Cold Formed Design to EC3. This is a Game changer for those engineers using portal frame constructions and trying to design the most efficient systems for those structures.
The next one is more in the link between our Advance Design platform and Autodesk Advance Steel for the transfer of model data, for this version we have a Newly design GUI and Mechanism for the Synchronization of Data using the Graitec GTCX file format. This new interface allows form many options to optimise what you wish to transfer and sync,
Within the file and the options available we have the ability to have a dedicated object ID, object type, Status display for New/Modified/Deleted, Material, Geometry, Element Type.
Having all these options, we now have also filter options available, to help you dig down and only see the data you require.
Also, the file has now the option to contain the level of the element within the model space. It has two options to show the host location and the allocated level in the GTCX itself.
Also, all important one for model Tolerance, this allows for the user to control during the Sync process the variation between the model elements is acceptable, based upon those numeric values.
Concrete elements are now also considered for the GTCX file and the transfer, presently standard column, and beam shapes for this version, but sure other more complex shape definitions will be added to this new feature.
There are a lot more elements and options to the GTCX and the New Sync process, these are explained in depth in the what’s new, that is available to customers via the Graitec Advantage site.
Powerpack Premium Steel – Stairs and Railings
Within the premium model, particularly for Stairs and Railings we have a great new feature for those working with panelised balustrades/railings, that is the inclusion of ‘Lugs’ to the panels.
We can now add vertical and horizonal/incline lugs.
This may only look like a small feature but for those of us that have to detail these, this will be a real time saver.
Anther part of the railings in the actual placement of panels within the rail, previously there where some limits on what we could achieve, but again the development team have worked on this to improve this function to accommodate more complex arrangements.
This also works with the frames type panels as well.
A new option is to allow for the user to turn off the top rail and still have the panels, this can be useful in the situation of external fencing panels and picket type fencing arrangements.
Advance Design allows creating a new type of steel slab/deck: non-composite steel slab. The non-composite slabs may be used as floors in lightweight structures or as a form for reinforced concrete slabs.
Steel decks are created directly in the graphic area. The procedure for creating a non-composite steel slab is similar to the ones for other slab type elements. The position of the slab is specified by entering the coordinates on the command line or by snapping to other objects. The plate type can be selected from the General > Type drop-down list in the Properties window.
The element’s attributes can be configured in the Properties window.
In the Properties window you can define the material type (according to the producer’s description), the type of profiled steel sheet, the steel deck connections, etc.
Let us assume we need to use a steel deck floor on the structure below (1-a). First, the position of the secondary beams (joists) is established as a function of the steel deck profile allowable span. For deck profile P3615-76, a span of 1950mm (1-b) is chosen.
The width of the profiled steel sheet is 914 mm and will be placed along the Y global direction. In order to properly consider the interaction with the joists, the 914 mm-wide deck sheets will be drawn one by one between them (2-a, 2-b). It is recommended to draw the deck parts in numerical order for a straightforward use of results. The steel deck definition is the same for all elements (3-a).
The lateral walls act like a diaphragm between the foundations and roof/floor. They take over wind pressures and distribute them at the horizontal level. The roof/floor diaphragm receives a linear load from the side wall.
We therefore run the analysis considering a linear load of 25kN/m (4-a). Advance Design automatically generates a set of four section cuts on each steel deck fragment.
The Steel deck diaphragm verification report provides the maximum shear diaphragm for each element. The value results by dividing the Txy section cut tensor to the side length. The shear diaphragm is then compared to the steel deck Shear Strength (5-a, custom table 5-b).
An efficient use of materials is met by using different steel decks and connections. Therefore, one adjusts the deck settings for all the elements on a row according to the Shear Design Load Rate deficit (6-a, -b, -c). If the capacity exceeds the shear diaphragm, the number of fasteners or the steel sheet thickness may be reduced (6-d).
In the second step, you can notice the material optimization achieved by the properties changes (custom table 7-a).
Real-time energy simulation ArchiWIZARD and his raytracing technology enables accurate and efficient simulation of solar and light radiation. Simulate and evaluate the impact of architectural and technical choices interactively and quickly to optimize the bioclimatic performance, including solar and light studies, of a project from the first sketches.
Results of light analysis in the bottom crossbar change in real time according to the modification of 3D model parameters by the user (for example building orientation, solar shading etc.).
Solar and light tools ArchiWIZARD has ergonomic and efficient tools to analyze in detail the sunshine, irradiation and natural light of projects and optimize the exploitation of solar and light resources. These features make it an essential solution for the visual and educational evaluation and demonstration of the choices made, whether for the installation of the building or the sizing of the bays, sun protection, photovoltaic installations, etc.
• Solar Imagery • Projected shadows • Solar receiver • Lighting map
These tools can be easily used through ArchiWIZARD intuitive interface:
2.1. SOLAR IMAGERY This feature allows to visualize solar radiation cumulation received on project surfaces. There 3 types of calculation:
Irradiation This represents the energy received by a point on a surface (walls, floors, roofs …) throughout the simulation period. The flux received depends on the climate, the position of the wall (orientation, tilt) and masks present.
Sun exposure This mode enables viewing of the time when a surface is exposed to direct sunlight compared to the time when the sun is up. Sun exposure [%] = time when the wall receives direct sunlight [h]/ sunshine time [h] The flux received depends on the climate, the position of the wall (orientation, tilt) and masks present.
Exposure to the ceiling grid This representation shows the percentage of ceiling grid “seen” per wall. The reference is a horizontal wall without a mask: its exposure to the ceiling grid is 100%. Accordingly, this parameter depends on the tilt of the walls and the mask presence. This map display reveals the impact of near and far masks on the project.
2.2. PROJECTED SHADOWS This feature allows to visualize the drop shadows of the stage (building and its environment). There is two mode:
Unique shadow Allows to visualize the shadow of the project and his environment on a specific time (month/day/hour/minute).
Multiple shadow Multiple shadows mode works as unique shadows mode. The difference is that the user can chose a step of time and visualize the evolution of the shadow for each step at the same times on the 3D model
2.3. SOLAR RECEIVER Solar receiver is used to quantify solar and natural light received by a defined area. This area can be placed manually by the user. The solar reception makes the difference between direct, indirect, and diffuse solar beam.
2.4. LIGHT MAP The lighting map enables display of the daylight factor or lux illumination received on a horizontal plane in the scene. It considers the geographical location, masks, the position of openings and their characteristics. Illumination with direct sunlight is also represented. Artificial lighting is not considered. This plan, represented by the map, can be positioned around the scene, interior as well as exterior of a project.
ArchiWIZARD has multiple tools to conduct studies on solar or light radiation from a project. These tools benefit from raytracing and allows accurate and adapted results.
Revit allows you to place bars in a structural element in a very flexible way. This gives a great flexibility for placing rebar in a host, or to model bars of any shaping. On the other hand, it also possible to model an unfeasible shape because basically, Revit do not contain many for constructive dispositions. However, some concepts exist such as concrete cover, which can be respected (with some additional tools when placing the bars).
When it comes to the shape of the bar itself, Revit allows you to create bars with no length limit. Thus, it is possible to create very long bars, without taking in account a maximum bar length for example.
The PowerPack Detailing allows you to address this topic with the Split Rebar command.
From a bar set distribution, this command will allow the distribution to be split according to different method.
Several options to configure the splitting of the bars are possible with this dialog box but two are mainly impacting on the result:
The method of splitting bars with three options proposed.
2. The method of connection for splitting bars with four options proposed
In addition, an option will allow the user to create an alternate distribution after splitting the rebar set.
Whichever splitting method is chosen, it will be possible to choose the direction of the cut and manage the distribution of each segment.
The possible configurations by this tool are therefore very important. It is just needed to select the rebar set to get the result.
The Railings, exactly like the stairs, are an important part of a building and used in many areas of it: balconies, decks, windows, roofs, stairs, and more.
In all these cases the support of the railing is different. It can be a concrete slab, concrete, steel or wood beam, a wall, basically any type of support.
Therefore, it can be very difficult to find the right way to build the railing without having the right support element.
Having this in mind, Graitec has developed the Railings macros available in the PowerPack for Advance Steel to be created independently of a support element.
Why is that possible and how? Because the Railing macros are designed to have 3 types of input! Each time a type of railing is created, the first thing that the user must define is the input type.
The input of the Graitec Railings can be: Points, Beams, Lines.
The “Beams” input is the most limited one, because to create the railing, beams must be selected. Therefore, if no beams are available for selection, no railing is created. Also, the shape described by the beams will be the railing shape. For example, curved railings cannot be created using beams as input.
This type of input is used especially for stairs with stringers made from straight beams, or on areas, like the platforms which the contour is made with beams.
The second input type, much more flexible than beams, is “Lines”. The selected lines can be straight, arc or polyline. The lines are offering a lot of flexibility, allowing to create different shapes of railings with multiple configurations.
The railing shape will be the one defined by the line/polyline shape. Creating curved railings will be as easy as the straight ones.
The third type of input “Points”, as the Lines, is offering a lot of flexibility and gives the user the possibility to build the railing directly where he needs it. No other preliminary preparation is needed, like creating beams or lines. Just to pay attention at the selected points.
The railing shape will be the one defined by the selected points.
The most important benefits of the Lines and Points input types are:
The railing can be created wherever we need in the building, and can be manage outside of the big model, where the full structure is created.
Multiple railing shape, straight, curved, mix of both.
No specific type of input is needed.
In the end, having multiple types of input to create the railings is offering infinite possibilities.
Climatic loads are a specific type of imposed loads to which almost every building object is exposed. Their nature and value is closely related to the type, geometry and location of the object. When preparing the design, the designer is obliged to include these loads in his calculations.
It has already happened in the past that incorrect consideration of this influence has led to disasters or failures. This aspect is often simplified or omitted due to a certain laboriousness of the determination of loads (especially wind loads) and their transfer to the calculation model, which will be the main subject of this article.
The current basis for the determination of climatic loads are Eurocode standards EN 1991-1-3 for snow loads and EN 1991-1-4 for wind loads.
In a similar way, these standards first determine the effect of the building location on the size of the characteristic load and divide the country into snow and wind load zones, respectively. The next step is to determine the nature of the load resulting from the geometry of the building itself – for wind it will be the external pressure zones and their distribution, while for snow it will be the roof shape factor. The whole is thus a basis and a relatively clear instruction for the determination of the ultimate snow and wind loads.
Automatic generation of loads in an FEA model
If the designer would like to determine these loads manually and apply them to the object in the calculation program, he has to reckon with a very labour-consuming task, mainly due to a multitude of coefficients leading to the final value and it is, so to say, complicated for even the simplest object. For example – we have to consider several wind directions, determine the range of external pressure zones, take into account the internal pressure, the value of pressure in individual zones, and to top it all off we have to take into account a number of dozens of variables and values (from dimensions, to location, to factors related to exposure, direction, terrain, etc.). The worst thing is that the whole thing is then drastically sensitive to change – a small change in the geometry of the building leads to a change in the external pressure zones.
Unfortunately, in most calculation programs we are forced to determine these actions manually and apply them in the form of loads to the FEM model of the structure, which often also requires us to prepare the model itself. Advance Design software has an automatic climatic load generator based on Eurocode, working on the principle of geometry discretisation to the appropriate standard schemes. The user does not have to impose any parameters connected with building geometry.
Above is a general diagram of how a climate load generator works (using wind as an example). Step 1 is practically just the preparation of the FE model for any subsequent analysis. However, it is important that the whole object is clad with cladding, i.e. panels, which do not have any mechanical properties but are only supposed to distribute the surface load on the structural elements. Their geometry is presented in step 2 – on this basis the program recognises the shape of the object and applies appropriate load schemes. Step 3 is the determination of the external pressure zones and the load values which are distributed from the cladding to the members and shells in step 4. In step 5 the final result, the wind load on the structure, is presented.
All these operations take place automatically and one could say that they are by default invisible for the user – the designer only prepares the geometry and as a result he gets the structure loaded by climatic actions. Importantly, any change to the design (geometry, assumptions etc.) allows the loads to be automatically updated to the current state of the model.
Guide to Advance Design generator
The 2020 version of the programme introduced a number of tools allowing to easily generate all cladding in an extremely short time e.g. by selecting linear/surface elements, by drawing or copying.
The cladding determines in which direction (x/y/xy/other defined by angle) it will distribute the load applied to its surface. It also determines certain parameters related to climatic loads.
The loads are determined from the parameters specified in the load cases.
The operation itself is trivial – the parameters we need to establish are those that are not possible to establish from the model but result from the project assumptions (altitude, thermal coefficient, terrain category, etc.).
After these two operations (cladding and load cases), the program is ready to generate loads. It will create exactly as many load cases as necessary from the point of view of uniform/nonuniform snow or different pressure values in the individual zones.
CNC2M – additional provisions for wind loads
Very importantly, the program implements the provisions of the CNC2M document. This document is a kind of annex to the French standars but it is universal in its nature regardless of the country. It defines rules for determining zones and pressure values for buildings much more complicated than those included in the general provisions of Eurocode, e.g. L-shaped or C-shaped buildings, awning canopies, additional provisions for wind shelters. In Poland we are not obliged to use such provisions, but it is a much more reliable approach than using a simple cuboid “cube” model for the whole building.
If you are new to Graitec Advance Design community then in this article we will draw your attention to useful tools that you may not have noticed in your first few weeks of work, but which can help you to complete your projects faster and more conveniently.
Generate, not draw …
One of Advance Design’s favorite features for advanced users is the ” … on selected” from the context menu under the right mouse button (PPM). These capabilities are available by selecting one or more elements. In this way you can quickly apply loads, insert supports, generate points, connections …. It couldn’t be easier.
2. Stay up to date with the parameters of the FEA model…
Another solution that is ideal to use when working with a model is the “Hint Label”. Its advantage is that it can be turned on and off via the “status bar” (see screenshot below) but it is also configurable. This way you can e.g. check the length of an element, coordinates of end points or corners of an object. Why is this so important? With “tooltips” there is less clicking (e.g. the “measure length” function) or “reading” into the parameters in the properties window…
3 Hide/Display FEA model objects with one click…
Finally, I chose a function that I as a user myself discovered very late…. i.e. access to the shortcut in the context menu (PPM) “Display…”. This is essentially a shortcut to the object display settings. What I liked about it is that I can “peel” the model of loads, cladding etc without having to click on the “Project Browser” which takes my attention away from the model content. In conjunction with the “isolate” function I can get at objects that are not system related.
Among the many functions constantly used when working with FEM models are such basic ones as object selection and filtering, i.e. controlling whether objects are visible or hidden. And while every FEM analysis program has these functions, what makes Advance Design stand out is its ease of use. So, let’s take a look at a few possibilities and see how easy we can use them.
Leaving aside the graphical selection, let us first look at the simplest selection, that is, by basic criteria.
Criteria selection is the most basic type of selection – for example, when you want to select all elements of a particular cross-section or material or thickness in a modeled structure. In this case, simply select the relevant criterion, for example material, from the list. A window opens automatically in which you can enter a criterion – for example, select one or more materials from a list.
Among the many such critters available it is worth noting two: by System and by Name, as are extremely useful for a quick selection, especially if we have defined systems and subsystems and modified the default element names.
Other interesting quick selection criteria are Previous selection, which is the restoration of a previously existing selection, and Vicinity, which selects objects that are in contact with the currently selected items.
But what if we want to combine multiple criteria? Then we simply open the Select by Criteria window (for example by using ALT+S shortcut) and on each tab choose the criteria we want to use. For example, when you want to select IPE 300 and IPE360 profiles that simultaneously belong to a system called Front Structure. Just select these options from the list and press OK.
Interestingly, with a single click, you can change the default setting that selects items that meet all criteria (Intersection mode) to a setting that selects items that meet at least one of the selected criteria (Union mode). In addition, the operation can be performed on an existing selection. As you can see complex criteria are very easy to operate. As mentioned earlier, splitting the model into systems makes the work much easier. For example, when we want to select elements from a given system, we just need to do it from the Project browser level.
Using the same method, you can instantly hide or isolate a section of the model. Furthermore, you can hide/show objects (including those contained in systems) even faster simply by double-clicking on the Project browser in the list. On this picture just by few quick double clicks on the Project browser only columns and rafters are displayed.
All of these are simple operations, but they make working in Advance Design seamless because of their easy access and simple use.
Often the objects which we design require a more detailed analysis at the level of a specified fragment of the structure or element. For this purpose, often the whole object is modelled for the purpose of vertical element dimensioning, and horizontal elements such as floors are designed in a separate model, assuming their certain static scheme as faithfully as possible reflecting the global behaviour of these separated elements.
The problem begins to appear when the separated element must be loaded also with the remaining fragment of the structure, which we wanted to get rid of in order to reduce the large model. For the simplest example – I would like to analyse a complicated foundation slab – its separation from the model will not help me much, because loads which dimension it are transferred from the whole structure by means of columns or walls. The simple conclusion from this…I can isolate the slab as long as I load it according to the building scheme.
Advance Design allows you to exchange the support reactions of one model for loads generated in another model.
At the moment I have a model of the entire building, which I can easily solve. However, I would like to divide the model e.g. into an underground and an aboveground part or into a foundation slab and the remaining part of the building. Maybe I need to analyse the foundation slab in detail and I need to reduce the size of the model to gain calculation time. Maybe I would like to divide the work into 2 workstations and leave the development of the ground slab to one of the co-workers and deal with the vertical elements of floor -1 or higher I am able to do this by creating, in a way, 2 independent models (e.g. of the said underground and aboveground part). The problem arises in the fact that the aboveground part will load the underground part, and I have just removed it from the model.
2 Foundation slab modelled on an elastic foundation, the part above the foundation slab supported by nominal rigid supports. At this point I can solve model one – i.e. the part above the foundation slab – without a problem.
Saving reactions to a file and importing them in another task
Above are examples of support reactions from permanent loads. Of course, we can transfer all reactions (displacement/rotation) from all cases.
Please note that reactions are usually presented as an inverse vector, i.e. as a response of a support – here, however, our vertical reaction is directed downwards, as it is later to be a load on a foundation slab. The reverse of reactions can be reversed by changing the program settings in the results tab by switching off the option “Include reactions on supports”. On the BIM tab, the user can export the reactions to a text file and import them into the foundation slab model in the same way. The load cases and the position of forces in space are preserved.
Importantly, I can import reactions at any time, meaning potential changes to the output model are not threatening. I can also modify the geometry of the foundation slab freely – the loads are not associated with it, they are in a specific space in the model and load the element underneath them. The forces are in the same load cases as in the original model so the combinations do not change. I could, however, combine the loads differently because in a smaller, detailed foundation slab design I will be able to successfully prepare more combinations.
The only thing I would like to point out is that it is necessary to separate structural elements sensibly. Their work under loads may be influenced by the elements that we have removed. That is, in addition to transferring loads, they also stiffen the component under consideration and change its working character somewhat. It is relatively correct to separate the whole storey.
This method can also lead to a kind of phasing of the structure.
Pushover analysis consists of 3 major phases, first the preprocessing phase in which the model is prepared for the analysis. Then, the processing phase during which the model is analyzed and finally the post processing phase where the results are interpreted.
1. Preprocessing phase:
the user first needs to define the plastic hinges at locations where they are expected to occur (ends of beams), or at locations where their arise needs to be monitored (ends of columns). The plastic hinges can be defined on individual linear elements from the properties panel.
Separately for each extremity, the user is able to select the degrees of freedom for which the hinge is applicable. The ID name of a plastic hinge is generated automatically, and it consists of prefix PLH-L (plastic hinge on linear element), ID of the element, the extremity (1 or 2) and the type of the element (B – for beams, C for columns). The definition of parameters of the plastic hinge can be done by using a dialog opened by a button on the Definition property.
In a case the user decides that hinge parameters are calculated automatically, he can select the code (EC 8-3 or FEMA 356) and element type. The list of types (steel or concrete beams and columns) depending on the selected code. The content of the part with properties also depends on the selected code. Note, that some of parameters are computed during the next stage, during the pushover analysis. In case the user decides to manually define hinge parameters, then after selecting the code can unlock and edit available parameters.
The next step is the creation of pushover load cases and generation of pushover loads. For this, a Pushover load case family type can be defined from the Create load case family. On its property list we can set the basic data for load generation such as: the distribution type, the point of application and the directions of the loads.
There are several load patterns available to distribute the pushover forces on the height of the structure:
Where Vb is the maximum total lateral load and Fn is the maximum lateral load applied on level n.
Using the right click menu on the PushOver load case family we can then automatically generate the pushover load cases and loads. On the property list of each generated pushover load case we can set details related to the maximum total lateral load and conditions for stopping the analysis.
The maximum total lateral load is the cumulated sum of the lateral loads applied on last step of the pushover analysis. This load can be defined either as the imposed value or as a percentage of the load applied on the structure prior to the pushover. For the second case we can use either the total gravity loads or the seismic base shear force on X or Y direction.
2. Processing phase:
The pushover analysis is a list of sequential actions, activated by a dedicated Pushover checkbox control in Calculation Sequence dialog
The pushover analysis is a static nonlinear analysis during which the structure will be pushed laterally until reaching the maximum specified lateral force or developing a failure mechanism.
3. Postprocessing phase:
As with normal static calculations, FEM results such as displacements and internal forces are available. The results can be checked as for the non-linear calculations for each of the subsequent calculation steps.
A Pushover Results entry is available on the FEM results selection that allows for selecting the Hinge status result for linear elements. When activated, it shows status of defined plastic hinges for selected step of the selected pushover case. The status is displayed by using colors.
Using the Pushover results curves command, available on the Results ribbon, a pushover capacity curve can be generated. It displays a relationship diagram of the displacement of control node with respect to the total applied lateral load.
The pushover capacity curve represents the structural capacity to resist lateral loading and is a reflection on how the structure will behave when loaded laterally (seismic loads). During earthquake, the structure will be pushed laterally until a certain maximum displacement of its control node (master node). The point on the pushover capacity curve having this maximum seismic displacement is called the performance point. Physically speaking, this performance point is the balance point between the structural capacity (pushover capacity curve) and the seismic demand (seismic response spectrum). Advance Design can calculate the performance point according to the Eurocode 8 N2 method and ATC 40 Capacity Spectrum Method.
Knowing the maximum lateral displacement provided by the performance point, the user can refer to the pushover step corresponding to this maximum displacement and check the locations and limit states of plastic hinges, inter story drifts …