Revit 2019 Tutorial Part 1 – Adding Vertical Bracing Systems

I still find many people asking what the best methods are for adding bracing to steel models, some are still using beams to try and model bracing, others still get into a bit of a mess with vertical bracing, more struggle with the representation on drawings.

I thought it was about time I created a tutorial on this subject, covering both horizontal and vertical bracing as well as some typical connections for adding those all-important details.

So first we need to look at some of the basics. In the images below, you can see Vertical, Horizontal and Roof Bracing.

Creating Vertical Bracing

When creating vertical bracing it is best to create a framing elevation. The framing elevation creates an elevation on the frame a few hundred millimetres deep and sets a working plane for the bracing.

You must use the dedicated brace command to efficiently add bracing.

You can roughly sketch the bracing that you require and then use the Properties Palette to fine tune the exact location of the bracing.

In the example below, you can see some vertical X-bracing, note that the start and end attachments are attached to the correct levels and you also have the option of adding offsets from each of these levels.

In this example we have used Equal Angle to create the bracing. Both angles are in the same plane and hence clash.

This can easily be resolved by using the y Offset Value on each member. The analytical line remains centred, but the physical elements will be located correctly.

The bracing is automatically represented in a plan view and can be tagged. The standard in the UK is to show a parallel line on the outside for bracing above and a parallel line on the inside for bracing below.

You can control the type of representation and spacing in the Structural Settings dialog box.

Finally, if you want to tidy up the bracing and make the drawings look a little better you can either use 2D detail components to represent a connection or use the connection tools to add 3D connections.

LawrenceH

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Tutorial – Transferring Pile caps from Revit to Robot using Dynamo

Many of you may already know that if you would like to design a pile cap for punching shear with Robot you need to manually model the pile cap as a panel and then manually set up all the piles and the footprint of the column. This can be a real pain when the geometry changes!

A better approach is to unleash the power of Dynamo to help model the analytical panels and nodes that can be used by Robot Structural Analysis. You will first need to make sure that the package ‘Structural Analysis for Dynamo’ has been installed.

You will then see a range of nodes that allow you to take Revit geometry into Dynamo and then create Autodesk Robot Structural Analysis elements. The main idea behind the process is to take the top surfaces of the pile caps and then build panels from these in Robot. We then take the footprint of the column and the pile diameters and model these as panel openings. In the example I have used you can see the Revit model and the panels and nodes that are created in Robot.

If there is enough interest I may create a full tutorial video for this process but if you can’t wait to test this out then you can download a large image of the Dynamo graph from here:

Dynamo Graph as Image

 

LawrenceH

RC Detailing Tutorial – Revit 2019

In this short tutorial we will look at the reinforcement of a simple column and foundation. The reinforcement is modelled manually to show you how reinforcement bar is placed in elements. We then schedule the reinforcement to BS8666:2005 and produce a simple drawing.

Here is the bending schedule shown below.

The tutorial is using the Excitech Revit RC template but everything else is standard Revit 2019.

Hope you enjoy the tutorial?

 

LawrenceH

Revit 2019 – New Steel Features

Well, it’s that time of year again to review the new features of Revit, seems to come round so fast. As I did last year, I will review the steel and concrete features as separate blog posts and videos as we have a raft of new features to look at!

If you would like to jump directly to the steel video then here is the link.

New Steel Ribbon

Autodesk are further extending the Level of detail that can be presented by adding specific modelling tools to extend the power of structural connections and end treatments. You now have dedicated tools to create notches, saw cuts, holes and chamfers and rounds to steelwork. This allows for a greater Level of Detail when modelling and these features can be directly linked to Advance Steel for full Automatic fabrication documents.

The use of these new tools will depend on the need for modelling to this level of detail. For example, bridges may require a greater Level of detail but a traditional steel frame modelled by an engineering consultant may not require any connection details, these will be added by the fabricator.

A particularly nice feature is the ability to use a standard connection and then break the connection into the fabrication elements such as plates, bolts, cuts etc. This allows for easy modifications to connections and the ability to create your own connections.

For a detailed look at each tool check out my video at the top of this post.

Enjoy,

LawrenceH

Autodesk React Structures and Autodesk Robot Structural Analysis – Futures?

Some years back in 2015 I reviewed the Technology Preview of Autodesk’s new structural analysis package, React Structures, a fresh-looking ‘brother’ of Robot Structural Analysis with better integration with Revit and Dynamo. The main advantage was a cleaner, easier to use interface along with simpler workflows.

Autodesk React Structures was in Technology Preview for many years and recently seemed to be retired, so what could have happened?

Before I speculate on possible futures, perhaps we can take look at some recent trends in the construction industry and the use of design software.

The last three to four years has seen a quantum leap in the use of BIM models to communicate design ideas, transfer information, understand risk and manage costs within large projects. In parallel, projects have become more and more complex and clients are demanding better buildings, with reduced fees in less time!

This all adds immense pressure on Structural Engineers to react to design changes and create new designs with maximum efficiency. Many of us will use multiple software products to create design and 3D models and the biggest challenge is the transfer of data without loss and the learning of many complex software tools.

Many of you will already be aware of the cloud based analysis currently in Revit (if not see the previous post). This type of workflow allows data to be seamlessly transferred without conversions or the loss of data and is preferable to the two-way link currently used with Revit and Robot. When Autodesk React Structures was started it seemed a sensible method to take an existing analysis tool and refresh this for the coming years. The rate of progress with BIM processes and software overtook this initial idea which is why Autodesk abandoned React Structures.

I believe the future solutions will be completely integrated and use the same common interface to control the design and analysis models as one, truly unified model. To imagine an early preview of this toolset you could use Revit, Robot Structural Analysis and Dynamo to get a truly ‘live’ environment to develop and analyse structures.

Structural Analysis for Dynamo allows you to access many of the results and data from Robot and store these in the Revit BIM model. For example, you can store the bar number, the Bar Forces and Stresses in each element. You can then use these results to optimise the design within Revit.

In the above image you can see the Structure Analysis for Dynamo package and nodes that are creating loads, running the calculations and then retrieving the results. The image below shows the same space truss with a completely dynamic link from Revit to Robot. Panels have been created in Robot from Revit for the glazing and well as the bars and supports.

The optimisation is the interesting area here, this is where I think Autodesk can really use the power of cloud based computing to rationalise, optimise and design structures more efficiently. Perhaps other FEA tools can be integrated into the database such as NASTRAN for complex shapes.

I am sure we will all keep our eye on any developments from Autodesk in this interesting and exciting area.

LawrenceH

Dynamo – Geometry Working Range

A recent small change in Dynamo was an error when geometry exceeds a certain size. The default working range is small (when working in millimetres) and will often produce an error with most Revit models.

Dynamo is unitless and when working in feet and inches the default setting would allow the user to model something up to 10,000 inches (254 meters)! However, in millimetres this is only 10 meters which can very easily be exceeded. In the image below, you can see the error.

The answer is to set the Geometry Working Range from the settings menu in Dynamo.

The working ranges are as follows:

Dynamo does have some useful visualisation tools for Work Planes and Coordinate Systems but these cannot currently be scaled and, as such, only show with small geometry.

Hope this helps,

lawrneceH

An Overview of Structural Analysis for Revit

A few years back I reviewed the Load Takedown add on for Revit. This has now been replaced with ‘Structural Analysis for Revit’ which many of you will now have included with the new Autodesk AEC Collections. So what can you do with this tool and how do you use it?

Let’s start with what it can do and where I would see this tool fitting into the process.

Here is a video Tutorial for the whole process.

Firstly, this service uses the cloud to analyse your structure and as such, you will need to have some cloud credits to spend on this. In my experience, many companies have hundreds of unused credits so this should not be a huge problem.

The Robot engine is used to take your analytical model from Revit, along with loads and load combinations and then present results back either in the format of a report, a web page or directly within the Revit environment.

I would see this being used as a preliminary tool to try a few ‘what if’ examples prior to in depth analysis.

Where to Start

Download the Structural Analysis Toolkit 2018 from here:

https://apps.autodesk.com/RVT/en/Detail/Index?id=4901636995211349921&appLang=en&os=Win64

Your Analyze Ribbon within Revit will now have the following tools displayed.

The Analytical Model

Your Analytical model must be accurate and have connectivity between all nodes otherwise the analysis will fail (this will not use any cloud credits).

It is a good idea to check the model in Revit prior to starting the cloud based analysis. Use the Filters tool in Visibility Graphics to check for unconnected nodes. Tutorial for this is here: http://youtu.be/J2_iddaJzLg

Check that your beam and columns have the correct release conditions as this will obviously affect the outcome of any analysis and cause instability in some cases.

Create the required Load Combinations

Starting the Analysis

Select the Analyse in Cloud tool.

A number of checks will be performed and you will then see the dialog box below. Here you can set the type of Analysis (Gravity or Static). In this example we will create a load take down so set the analysis to Gravity and click start.

Once the analysis is complete you can view the results in a simple report, in Revit or review the model and various results live in the web page.

Here are the results displayed live in the webpage.

Hope this was useful,

LawrenceH