The Dark Arts of Revit: Conceptual Modeling Tools and Computational Logic in Structural Design

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1 Session 3 The Dark Arts of Revit: Conceptual Modeling Tools and Computational Logic in Structural Design hvasshaug@gmail.com Class Description Revit software provides tools for using conceptual modeling and computational logic in an advanced Building Information Modeling environment. Can these tools be used in Structural Design? This presentation will show how to play with Adaptive Components, patterns, repeaters, math and Dynamo to create structures and components that challenge the generic modeling capabilities of Revit. Complex concrete forms, post-tension concrete reinforcement and trigonometry-driven steel frameworks will be covered in a wonderful symbiosis of fantasy exercises and real-world project problems. Let s succumb to the Dark Arts of Revit About the Speaker Håvard Vasshaug is a structural engineer, Revit power user and Digital Design Manager at Dark, one of Norway's largest planning, architecture and interior design practices. He has vast experience providing Revit training, solutions and seminars for architects and engineers the past 8 years, and now uses this background to share knowledge of Revit solutions at Dark and to whoever else that enjoys it. Håvard is a regular presenter at Autodesk University and Revit Technology Conferences around the world. He is an enthusiastic blogger and national Revit forum administrator. Collaborating with Autodesk, he is a part of the Autodesk BIM Open Source Project Steering Committee, a dedicated Revit development contributor and a very proud Revit Gunslinger.

2 Introduction As I see it, there are two main reasons for learning conceptual modeling and computational logic in structural design. First, and most obvious, this way of operating allows us to design more complex, organic and optimized structural shapes faster than with traditional modeling tools. We can evaluate multiple structural options with great ease, and build beautiful structures based on natural and mathematical principles rather than clicking and dragging. Second, and perhaps less obvious, visual programming in Revit through Dynamo offers us a way of expanding the boundaries of what actually can be accomplished in a BIM tool. We can access and edit Revit projects and families at a completely different level of effectiveness and availability than traditional hardcoded tools allow. We can establish relationships between objects that Revit normally can t, and create elements using external data normally reserved for the software code knowledgeable. In short, we can create, and obtain deep understanding of, our own design tools; a glimpse into the future. In this class, and handout document, we will focus almost exclusively on the first part, but in doing so also touch aspects of the second. I am passionate about empowering young engineers and architects with knowledge of exceptional digital design tools, and firmly believe this to be the next generation for many of them. Note All information in this class handout is based on the following software versions: 1. Conceptual Modeling; Revit 2015 Build _1515(x64) 2. Dynamo; Revit _2115(x64) Update Release 2 and Dynamo If any of my examples deviate from your experience, please run a check on the versions you are using. Page 2 of 58

3 Table of Contents Table of Contents... 3 Conceptual Modeling... 4 Modeling a Space Frame using Massing, Adaptive Components and math... 4 Building a Grid System... 5 Dynamo Modeling a Space Frame using a graphical algorithm editor Building a Grid System Integration with Revit Elements Computational Frame Attractor Thickness Analytical Model and Structural Analysis Material for Further Research and Development Dynamic Relaxation Working with Adaptive Components and Structural Framing Working with Load Data inside Dynamo Page 3 of 58

4 Conceptual Modeling Modeling a Space Frame using Massing, Adaptive Components and math The use of mathematical logic in formulas in Revit Families to automate behavior is well known. But the power of math really comes to play when we use it with Adaptive Components and the different ways these families can be used. There is a whole lot that can be said about different behaviors, settings and use within the Conceptual Modeling Environment (CME) in Revit and Vasari. We ll save all the theory for another time, but before we start our structural exercise, let s get the key concepts and relationships in place. Playing with Adaptive Components and Masses is really about points, lines and planes, and generic geometry. Both Masses and Adaptive Components are Revit Families. Masses have their own Revit Category, and normally host Adaptive Components, although Adaptive Components are perfectly capable of existing independent in the Revit Project environment. Adaptive Components are recognized by Adaptive Points, and this is unique for these elements in Revit, as no other family have these. Adaptive Points are placement points that can be hosted by other geometry or moved freely in 3 dimensions. Typical geometry for hosting Adaptive Points is Surfaces, Divided Surfaces, Nodes and Divided Paths. When we host Adaptive Components on Divided Surfaces (using nodes) and Divided Paths, we can utilize the Repeat command that Revit offers in the CME. This offers a host of automatic behavior, especially when combined with mathematical formulas. Now let s see how this all works in a Structural Space Frame exercise. Page 4 of 58

Building a Grid System We can lay out a parametric grid system by using a Surface and the Divide Surface. This can be modeled in several different ways.

5 Building a Grid System We can lay out a parametric grid system by using a Surface and the Divide Surface. This can be modeled in several different ways. Here, we start by making a new Mass family, placing a Reference Point in the intersection of the two default Reference Planes, drawing a Model Rectangle around it, and constraining the Rectangle dimensions with Equals and Labels. Please note that we can create a surface fast by using the tick mark Make surface from closed loops when drawing the Model Rectangle. Page 5 of 58

6 When we ve checked that the geometry reacts to parameter changes, we can select the Surface and click the Divide Surface command. This creates a rectangular grid on our surface, and we can control the number or size of divisions by applying a Label to the Divided Surface U and V parameters. Here we use Layout Fixed Distance and associate the Distance parameter with a new custom Distance Label. We can then proceed with revealing the Divided Surface Node Points by changing the Surface Representation to Nodes. Page 6 of 58

We create a new Generic Model Adaptive family, and place 5 Adaptive Points, 4 of which will serve as Divided Surface node points, and the fifth on

7 Finally, let s model an independent Reference Point somewhere on the Surface (or outside). This will be the attractor focus of our computation. Now we have access to the points we need to distribute the Adaptive Component Frame family. We need to proceed by making the component. We create a new Generic Model Adaptive family, and place 5 Adaptive Points, 4 of which will serve as Divided Surface node points, and the fifth on the attractor Reference Point. The 5 points can really be anywhere, but our preview of the family will benefit from a layout similar to the final product. Page 7 of 58

We can continue by connecting the 4 node points with Reference Lines. In addition we connect Adaptive Point 1 (the attractor point) and all the other Adaptive Points using Reference Lines.

8 We can continue by connecting the 4 node points with Reference Lines. In addition we connect Adaptive Point 1 (the attractor point) and all the other Adaptive Points using Reference Lines. This is to report the length between the attractor point and each node point. Remember to use 3D snapping when drawing the Reference Lines, or else they will be constrained by the Reference Level. Last we can model the center point of the panel by adding two Reference Lines between each midpoint of the 4 nodal Reference Lines. Next we add 4 Aligned Dimensions between Adaptive Point 1 and all the other points. We want these Dimensions to always report the shortest distance between these points, as opposed to the orthogonal distance, and to obtain this we need to host the Dimensions on each corresponding Reference Line by clicking Set Work Plane and selecting the Reference Line before placing the Dimension. When the Dimensions are in place and working, we add a Label to each and use a custom Reporting Instance Length Parameter. Page 8 of 58

9 To work out the vertical and diagonal frames we add hosted Reference Points to the 4 nodal Reference Points. Using the same procedure as with the Dimensions, we click Set Work Plane and select each Adaptive Point s horizontal work plane, before placing a Reference Point on the corresponding Adaptive Point. This can be a bit tricky, but once we have the 4 Reference Points in place, we can select them one at the time and associate their respective Offset parameters with a new custom Length Instance Parameter. Page 9 of 58

It s important that while placing the Reference Point, Draw on Face is active. If not, the point won t be hosted by the line.

10 Next up we add a new Reference Point to one of the center Reference Lines, select it and click Host Point By Intersection. This will force the Reference Point to always be in the center of the panel. It s important that while placing the Reference Point, Draw on Face is active. If not, the point won t be hosted by the line. We finalize the geometric rig of the component by connecting the 4 nodal offset points with Reference Lines, and also the center Reference Point. Finalize the geometry by adding hosted Reference Points, radial Page 10 of 58

11 Reference Lines and sweeps using the Create Form tool (appears after selection of valid geometric rig). Now comes the interesting part; adding mathematical relationships between the parameters. In this example we ll use the Pythagorean Theorem to obtain a sphere-like bottom frame layout. Page 11 of 58

12 Translated to Revit Formulas, we get something like this: Page 12 of 58

13 Notice that we ve added a constant to the equation to be able to scale the entire frame. This is just a simple Instance Number Parameter. Now we can try moving the Adaptive Point 1 (attractor point) around, and observe the 4 different nodal Reference Points changing their offset values, all based on their linear distance to the attractor point. Next up we load this family into our Mass family that contains the Divided Surface. We place the Adaptive Component, first on our attractor Reference Point, and then in turn on the 4 nodal points of a given quadrant. When we are doing this it s important that we place points in the same sequence as the number of our Adaptive Points. Before proceeding we need to associate the parameters of the component with the ones of the Mass. Page 13 of 58

14 Finishing the space frame is now easy by using the Repeat command. We select the Adaptive Component, and by pressing Repeat it fills out the remaining quadrants of the Divided Surface. The rest is done by Pythagoras. Page 14 of 58

15 We can change the Mass parameters or try moving the Reference Point around. Updating repeated Adaptive Components can be a bit on the slow side, and often it can help on performance to load a simple family with only Model Lines and not solid geometry first. We can also build out a top frame layer with glass ceiling if we want. This can be done by either adding geometry to the Adaptive Component, make a new Adaptive Component or using a custom Curtain Panel pattern-based. Page 15 of 58

16 And we can add a solid sphere to the underside of the Mass to visually compare the placement of the straight bottom spherical layout to a real sphere. Page 16 of 58

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18 Dynamo Modeling a Space Frame using a graphical algorithm editor Using computational logic in structural design with the visual programming interface of Dynamo opens new possibilities after becoming familiar with the Conceptual Modeling Environment. Within Dynamo we can interact with, and automate processes in Revit, and build complex and logic structures with minimal energy. All it takes is a new way of thinking. Let s first see how we can get up and running. Building a Grid System In this section we will build a computational 3-dimensional attractor grid system that we will use later. Dynamo automatically associates itself with the Revit document that is open when open a definition or start a new one. A dynamo definition can run on top of a Revit project or family file, but what you can do with Dynamo depends on where you are. We ll touch on that later. We can build a basic computational grid system in Dynamo using any type of Revit document, but if we want to generate actual Revit Structural Framing elements we need to be in a RVT-file. We start by pulling out 3 Number nodes, a Number Range, an XYZ component and a Watch node, wiring them like below. Then, we can right-click on the XYZ node and change Lacing to Cross-Product. For more information on how Lacing works I suggest the Dynamo Learning video tutorials. Page 18 of 58

19 Figure 1 A square grid system Figure 2 Lacing explained by David Wood at bimwood.blogspot.com We now have a square grid system of 9 by 9 points. Note that these points are Dynamo arbitrary geometry, and has nothing to do with Revit yet. Also note that making a grid this way makes a list of lists, with each value of X in each sublist. This will help us when working out a set of lines. We can add another XYZ node, one more Number node and two Number Slider nodes, to add a new point in our preview background canvas. We can use this point as the attractor in our 3D grid. Page 19 of 58

We will use this to manipulate the Z values with some computation.

20 Now we add an XYZ Distance node to calculate the distances between each point in the grid and the single point. We continue by adding XYZ X and XYZ Y components to pull out the X, Y and Z coordinates. We will use this to manipulate the Z values with some computation. We also add two Number Sliders and a Formula node. The Number Sliders will control different aspects of the offset and amplitude of Page 20 of 58

21 our 3D grid. The Formula nodes have a text field, and in this field write the syntax a-(d/c). This will let us control the vertical offset with one Number Slider and the amplitude (or scale) with the other. Now we can connect everything again by introducing another XYZ component and wiring it to the XYZ X, XYZ Y and Formula nodes. Page 21 of 58

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23 We can add lines between the points in the grid now by adding a Lines Through Points node. We can add transversal lines by transposing the lists of XYZ coordinates produced by the last XYZ component, and wiring the transposed lists to a new Lines Through Points node. Page 23 of 58

24 The Lines Through Points nodes generate linear line segments between each point in a list. We can use continuous splines if we wish by using the Hermite Spline nodes similarly. Now we can change the different Number input values using the sliders, and see our model update accordingly. Now let s see what we can make of this in Revit. Page 24 of 58

Integration with Revit Elements One major experienced difference between dealing with Dynamo geometry and Revit Elements is that viewing, changing and interacting with Dynamo geometry is superfast.

25 Integration with Revit Elements One major experienced difference between dealing with Dynamo geometry and Revit Elements is that viewing, changing and interacting with Dynamo geometry is superfast. The same cannot always be said about Revit geometry. Still, one of the great advantages with Dynamo is that it actually can interact with Revit Elements. Let s have a look at how that works. Surfaces When talking about Revit, Dynamo and surfaces it s important to differentiate between modeling a Revit Surface with Dynamo and using a Revit surface in Dynamo. Creating a Revit Surface within Dynamo limits us to only work in the Conceptual Modeling Environment, as that s the only place a Revit Surface can be modeled and edited. Using an already modeled surface with Dynamo on the other hand, creates many possibilities. In fact, selecting Revit surfaces in Dynamo includes every surface in Revit, not only Masses created in the CME. We can use Walls, Floors and Roofs, anything that has a face really. In the Revit project we used in the previous section, model (in-place) or load a Mass surface. We can pull this surface into our Dynamo definition by adding the Select Face node, click Select Instance and click on the surface in Revit. Page 25 of 58

26 Now we can divide this face in a similar grid system like we used in the previous section. In order to do so we have to generate a UV grid, and convert it to XYZ points. We can do this by adding the Get Surface Domain, UV Grid and Evaluate Surface nodes, in addition to a Number node for U and V direction counts. Page 26 of 58

Using the line grids from the previous section, we can wire the surface XYZ coordinate list into the Lines Through Points and Hermite Spline nodes, but in order to make these work together we have to

27 Using the line grids from the previous section, we can wire the surface XYZ coordinate list into the Lines Through Points and Hermite Spline nodes, but in order to make these work together we have to manually make sublists of each gridline. We can do this by using a Partition List node together with the Number Node that controls the U and V count. This way our partition lists will always correspond to the number of surface divisions. There is one slight detail we must not forget while doing this, and that is the number of divisions (8 here) is 1 less that the number of points along one gridline. Hence we must use a Formula node with the syntax a+1 between the Number node and the n input in the Partition List node. This way the number of partitions will always be one more than the UV count. PS We do not want to delete the XYZ Distance and Formula nodes used previously, as they will come in handy later. Page 27 of 58

We can further develop this grid by finding the center points of each panel and offsetting these normally to the surface. To do this we need two nodes. First we need to use the Best Fit Plane node.

28 We can further develop this grid by finding the center points of each panel and offsetting these normally to the surface. To do this we need two nodes. First we need to use the Best Fit Plane node. This will find the midpoint between a set of XYZs. Second we need a custom node called LunchBox Quad Grid by Face by Nathan Miller. This will, with the help of a little Python programming, get the quadrant points as lists of lists. We need this to get the best fit plane per quadrant. These quad points can also be obtained manually without the help of custom nodes and Python programming, but that requires much more list manipulation, and we will not cover that here. Page 28 of 58

Finishing this section we can offset the center points by using the Normal output from the Best Fit Plane node.

29 We can visualize the center points easier by right clicking on the Select Face node and disabling Preview. This will turn off the surface in the background preview. Finishing this section we can offset the center points by using the Normal output from the Best Fit Plane node. This output is a list of XYZs that represent the normalized vectors for the axis of the best fit plane. We can use this vector by adding a Scale XYZ node, a Translate Transform node and a Transform XYZ node. Page 29 of 58

Next we wire the Number Slider used as the vertical offset parameter for the grid in the previous example as the n input in the Scale XYZ node, and the rest as follows.

The last thing we need to do is combine the quad points with the respective offset points into lists of 5 XYZ coordinates.

30 Next we wire the Number Slider used as the vertical offset parameter for the grid in the previous example as the n input in the Scale XYZ node, and the rest as follows. The Transform XYZ node now generates vectorized offset points for each quadrant, and we can control the offset value using a single Number Slider. The last thing we need to do is combine the quad points with the respective offset points into lists of 5 XYZ coordinates. We can do this by using a Transpose List node on the LunchBox Quad Grid by Face node and adding that list to the Transform XYZ output by using an Add to List node. Following that with another Transpose List node gives us a list of the XYZ coordinates of all quads and their respective offset points. Page 30 of 58

XYZs node. This node requires a list of XYZ coordinates that define the location of the Adaptive Points in the family.

31 This provides a nice platform to start modeling Revit Elements, and first off are Adaptive Components. Adaptive Components There are a couple of different Adaptive Component nodes in Dynamo, but the most commonly used is the Adaptive Component by XYZs node. This node requires a list of XYZ coordinates that define the location of the Adaptive Points in the family. The number of XYZ coordinates must equal the number of Adaptive Points. Also, we need to keep in mind the number sequence of the Dynamo points when building our Adaptive Component. Dynamo always counts Page 31 of 58

We introduce the Adaptive Component by XYZs and the Select Family

32 from 0, while Adaptive Components start at 1; hence 0 correspond to 1, 1 to 2, and so on. We introduce the Adaptive Component by XYZs and the Select Family Type nodes, make sure our 5-point Adaptive Component is loaded into our Revit document, and wire the nodes. Page 32 of 58

33 This offers many possibilities when it comes to complex, organic and effective modeling, and also lets us evaluate many different options with minimal energy. For instance, we can turn on Run Automatically in Dynamo and change the Revit Surface. The entire component layout updates instantly. One thing we cannot do with Adaptive Components however is use them for structural analysis purposes. These Revit families have no corresponding Analytical model, cannot host loads or Boundary Conditions, and can t be exported to analytical software. (This is actually only partly true, as we ll discuss later.) One Revit element that can do all these things is Structural Framing, and guess what; there is a Structural Framing node in dynamo! Structural Framing The Structural Framing node in Dynamo populates a Revit project document with beams that we can use for analytical purposes. The node requires three inputs; Structural Framing Type, Model Curves and an Up Vector. The Select Structural Framing Type node in turn needs at least one loaded Structural Framing family in the active project. Page 33 of 58

Without having too much detailed knowledge of why, it is a general impression that the Structural Framing families work best with Dynamo if they are defined without the automatic cutback feature of

34 Without having too much detailed knowledge of why, it is a general impression that the Structural Framing families work best with Dynamo if they are defined without the automatic cutback feature of Revit. This feature has a tendency to over-scale the cutback, and although this does not (normally) effect the Analytical Beams our models look much better. The curves input require a flat list of Dynamo Model Curves. Normally Line by Endpoints, Lines Through Points or Hermite Spline does the trick, depending on what our beams look like (is it a spline or linear line?) and what list data we have. Page 34 of 58

35 The Up Vector is a tricky one. It gives us the ability to control the orientation of every beam generated by Dynamo. But to make it work properly we have to provide the exact same number of up vectors as there are beams, regardless of how many different up vectors we need. For instance, if all beams generated from a node are going to be vertical we still have to define a list of vertical vectors and not one single value. Last, we really only need one Structural Framing node for each different Structural Framing Type and up vector. Combining all lists of model curves with a List node, and making sure we flatten the resulting list, as the Structural Framing node only works with a single list of curves, we acquire the desired outcome; a complete set of Structural Framing elements in Revit. Page 35 of 58

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37 Now with the bottom space frame in place we can continue by adding a top layer and a vertical grid. We already have all the points, but need some list manipulation. Starting with the vertical grid structure we need to combine each bottom point with the corresponding top point. Each quadrant will have 4 beams meeting at the center offset point. We can work out this by developing a list where a corresponding offset point is added to each quadrant point. Now we can add one center offset point (output of the Transform XYZ node) to each point by repeating the center offset points equal to the number of quad points. We do this by pulling out one of the sublists, extracting its list length and repeating the center offset points by that quantity. Alternatively we could just add a Number node with value 4, as our grid is a quad grid, but in case we want to develop a different form (diamond, staggered, etc.) later this may provide flexibility. Adding a Get from List with index 0 will pull out the first sublist. Using a List Length node on Element output will return the number of each quadrant point, and we can use this number to repeat the center offset points (the Transform XYZ output). Page 37 of 58

38 Now we have all the start and end points for our lines, and all that is left is adding a Line by Endpoints node and using the transposed quad grid and the repeated center offset points as input. Page 38 of 58

39 Adding these lines to the combined list of lines we can start adding a vertical grid of Structural Framing elements to the Structural Framing node in our definition. Page 39 of 58

40 The Structural Framing node does not always update already modeled Structural Framing correctly, and rather model new. Adding a new list of lines to the generation of beams sometimes result in this unwanted behavior. We can avoid this problem by either deleting the beams from Revit, or deleting and replacing the Structural Framing node in Dynamo. Either solution will result in new beams, and no duplicate elements. Page 40 of 58

This list of points is flat, and like for the bottom grid we need to partition the list with the number of grid lines.

41 Working out the top grid should be fairly simple now, connecting all the quad center offset points. As mentioned previously, these points are outputs from the Transform XYZ node deriving from the Best Fit Plane. This list of points is flat, and like for the bottom grid we need to partition the list with the number of grid lines. Since the number of center points equal the number of quads (and U and V divisions) we can pull this number from the defining Number parameter that generates our grid count. Page 41 of 58

direction, generates the model curves we need.

42 Wiring the partitioned list into two Lines Through Points, one of them via a Transpose List node that provides for the transversal direction, generates the model curves we need. Finishing by including these curves in the List node, our Space Frame is complete. Page 42 of 58

43 Again, we can turn on Run Automatically in Dynamo and make geometrical changes to the Mass Surface, or change the UV count or vertical grid offset. Page 43 of 58

Computational Frame Attractor Thickness With the complete Space Frame layout and the possibilities in Dynamo, it s quite tempting to work out some more advanced geometric manipulations.

44 Computational Frame Attractor Thickness With the complete Space Frame layout and the possibilities in Dynamo, it s quite tempting to work out some more advanced geometric manipulations. One that is quite easy to implement uses the attractor concept of our first sections. The center point normal offset distance does not have to be equal for all quadrants. We can give the entire frame a different form by computing separate offsets for each quad. One way to do this, and one we used in the first Dynamo section, is calculating the distance from one given XYZ coordinate to each grid or quad point. The XYZ coordinate can be anything from a Dynamo XYZ, a UV coordinate or a Revit Reference Point. If we want the point to always be in the center of the surface, we can copy the UV Grid definitions, and make a single 2 by 2 grid, from where the center point of the grid will serve as the center point of the surface. Page 44 of 58

continue with a Formula node and the syntax ((a+1)*(a+1))/2.

45 We can get the center point from the UV Grid by using a Get from List node with either a Number or Formula node. It doesn t really matter as the division will always be 2 by 2, but by following the principle of flexibility we continue with a Formula node and the syntax ((a+1)*(a+1))/2. This will force all even number inputs to produce a center point. Now we can continue to use the XYZ Distance and Formula node we created in the first sections. Page 45 of 58

46 We delete the Number Sliders, Number and XYZ components, and wire the XYZ Distance to our new center point and the Best Fit Plane origin. The Number Slider that previously parameterized the XYZ Scale node can now be wired out of the Scale XYZ n input, and just remain in the Formula a input. Finally, we change the formula to the syntax a+(d/c) where a is a constant offset and c is amplitude, and wire the output to the n input of the Scale XYZ node. We should remember to de-wire the Structural Framing node before executing the definition now, because updating will be much slower when Revit beams are generated or updated. Mess around with the different parameters and then wire the Structural Framing node when the Background Preview looks like something you re not embarrassed to show someone. Page 46 of 58

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Analytical Model and Structural Analysis With the introduction of Structural Framing and subsequent Analytical Beams we can start to explore the possibilities of structural analysis.

50 Analytical Model and Structural Analysis With the introduction of Structural Framing and subsequent Analytical Beams we can start to explore the possibilities of structural analysis. First, we can start adding vertical Hosted Line Loads for Live Load. If the Steel Sections we have used in Dynamo are somewhere what we want to design we can use them for Dead Load. Otherwise we provide dead load too as Hosted Line Loads. There is no way to use Area Loads sadly, as that require planar Structural Floor elements, something we do not have here. Page 50 of 58

Of course adding new beams will require manually modeling new loads, but most

51 It s interesting to note that the Hosted Line Loads will update with the Analytical Beams when we change certain parameters in Dynamo. Of course adding new beams will require manually modeling new loads, but most updates that either move or deletes load will update. Boundary Conditions can also be added quick and easy. Page 51 of 58

52 When all this is in place we have some options to proceed. First, we can use Autodesk 360 Structural Analysis to perform simple calculations and analyze and visualize the results in Revit. Page 52 of 58

53 We can even bring in and visualize deformation in a Revit View. We can also use Revit Extensions to get quick and easy Load data at supports and different members. Page 53 of 58

54 The Revit Extensions can also save reaction loads back to Revit as native Revit Internal Point Loads at supports. Page 54 of 58

We can export our analytical model to Robot Structural Analysis Professional and perform detailed and complete automated load combinations, calculations and steel section dimensioning.

55 We can export our analytical model to Robot Structural Analysis Professional and perform detailed and complete automated load combinations, calculations and steel section dimensioning. After optimizing the steel sections in Robot, the updated members can be brought back to Revit. Last we can export node and line data directly from Dynamo to Excel or CSV, and bring this into whatever analysis software we use. We can easily differentiate between different sets of points and lines in a dynamo definition, and extracting that information is done by simply wiring the following sets of nodes: Page 55 of 58

56 Similarly we can export the same data to CSV. Many structural analysis programs can import analytical data from Revit, but in case that for some reason fails, nothing can go wrong with numerical Excel data. Page 56 of 58

Material for Further Research and Development Dynamic Relaxation In the sample library of Dynamo there is an exercise called Dynamic Relaxation.

57 Material for Further Research and Development Dynamic Relaxation In the sample library of Dynamo there is an exercise called Dynamic Relaxation. This definition creates a Particle System from any given points and curves, in addition to a host of numerical data (including gravity), and loops this data in a set of iterations that freezes in a position where all members have ideal stress. In our example, we should be able to apply this concept on our doublecurved surface, and generate a pressure-optimized space frame in Dynamo, rather than the one we made from guessing and analyzing. However, in the current versions of Dynamo these nodes does not work properly, and either crashes or never returns from the loop. When these nodes start working properly I see a lot of potential for great use when working with structural optimization. Page 57 of 58

58 Working with Adaptive Components and Structural Framing As engineers a very likely scenario on AEC projects includes us receiving an already modeled structural system from an architect, using Adaptive Components rather than Structural Framing. As we discussed earlier, this is great for modeling flexibility, but provides no analytical data. Rather than modeling a structure over again, or modifying an architectural definition, we could extract point and line data from the Adaptive Components using Dynamo, and use these to work with structural analysis. Whether passing them on directly to analytical software or generating Revit Analytical Elements, this provides us with the opportunity to work fast with correct data. The time saved on not remodeling could be used on analyzing many more options instead. This would also work with updated models, say, if we receive a new set of Adaptive Components from the architectural design team. Working with Load Data inside Dynamo One problem described earlier, and a major workflow issue is the fact that we have to model loads manually and separately, either in Revit as Line Loads or in Robot using Cladding and Area Loads. This presents us with ineffective labor and design change problems, for instance when changing the UV Grid. Working only with Line Loads in Revit, as opposed to Area Loads, is also fairly time consuming, as it presents conversion operations when all available load data is described by areas, and lots of clicking. A solution for this could either be some kind of Load Nodes or Load input for Structural Framing that lets us apply load data to elements, or maybe even areal load data to surfaces. Page 58 of 58

Computational Logic in Structural Design

Session 11 Computational Logic in Structural Design hvasshaug@gmail.com Class Description The visual programming interface of Dynamo is enabling structural engineers with the tools to build optimized structures