Revit 2020.2 Coordinate Systems

Happy 2020 to everyone. You may notice that I have created a new look and feel for the site, the original site going back to April 2009! Hope you like the new logo and appearance?

Anyone who authors Revit models or works with 3^rd party consultants that use Revit has surely experienced poorly coordinated models and struggled to understand why models do not federate and overlay as expected.

Many of these issues are simply down to a lack of understanding of the Revit coordinate system or properly communicated BEP’s, but these are fundamental to the correct setting out and coordination of projects. Revit 2020.2 offers some help by being able to visualise the Project base Point, Survey Point and the Internal Point within linked models. Also, you can no longer unclip the Project Base Point, meaning that the Internal and Project Base Point are normally consistent, however, see the note at the end of the post!

The image below is displaying the two Project Base Points, the blue being from the active project and the grey being from the linked model

Here you can also see that the Internal Origin point is also displayed in grey on a linked project. This is useful when checking that the Project Base Point and Internal Origin are overlayed.

When a linked model is selected the Project Base Point shows the linked model icon and the relevant properties such as the North/South, East/West, Elevation as well as the angle to true north. Very useful when trying to understand why Revit models will not federate and overlay correctly.

As many of you will already know, Revit has an internal origin which can be different from the Project Base Point. The Internal Origin point can now be displayed with a new sub category within the Site category.

When setting the Project Base Point you should now use Specify Coordinates at Point or acquire coordinates rather than directly selecting the Project Base Point and moving.  You will notice that selecting the PBP and using the Properties Palette or directly typing the coordinates will move the PBP independently of the internal origin.

LawrenceH

Happy Holidays!

Wishing all my readers and viewers a very happy Christmas break and hope that you have a prosperous New Year. See you in 2020!

LawrenceH

Coordinate Scheduling with the Excitech Toolkit

The original Excitech Revit toolkit was created in 2009 to produce coordinate schedules of elements such as isolated foundations, structural columns and any family with a single insertion point. The toolkit provided a solution to those customers who needed to produce piling schedules. An extension to the toolkit was added in 2012 to allow the automatic renumbering of elements, again aimed at piling.

The new Excitech Toolkit was introduced in 2018 and contains a greater number of tools and utilities to improve productivity in a number of different areas. The new toolkit also provides the option of scheduling coordinates from elements.

Please see the video for a tutorial on how our toolkit is used to schedule coordinates.

 

Here you can see the tutorial for the new Revit Excitech Toolkit.

Below is the procedure to create a piling schedule and renumber the piles using our new toolkit.

1. First you select the piles that are required to have coordinates. If you have used a foundation family that has piles nested into the pile cap then you will need to select the sub elements.

On the Excitech Toolkit ribbon in the Selection panel click the Filter command as shown below.

In the Filter dialog box select Structural Foundations and then the pile sub elements that you have used in your project.

Click OK to make the selection.

2. On the Excitech Toolkit ribbon in the Analysis panel, click the Analyse drop down menu and select Insertion as shown below.

You will then see the Insertion Point to Parameter dialog box. Here you can select the internal origin of Revit, the Project Base Point or the Survey Point. For piling that has been set out using shared coordinates, click Survey Point.

Click OK

3. Each pile will now have the following coordinates added. X coordinate, Y coordinate and Z coordinate. These coordinates are at the toe of the pile. X Top Coordinate, Y Top Coordinate and Z Top Coordinate are positioned at the top of the pile (this would also be the cut off level)

 

Revit – Setting out and scheduling coordinates from grids with Dynamo

I have had a few questions around detailing coordinates of grid intersections with Revit. You may already know that it is tricky to add spot coordinates to each grid intersection as Revit will not ‘snap’ to the grid intersection. You can add reference planes across the grid intersections, but this is quite time consuming and prone to error.

I have created a Dynamo script to place down a setting out family at each grid intersection and record the grid intersection, Easting and Northing at each location. This has the added value of being exposed in Navisworks or an IFC model for a contractor. We can also schedule the coordinates of each grid intersection and present this onto drawings or export to Microsoft Excel for input into site instruments.

Update!

Thanks to Christoph for providing a Python script to replace the convert to number node. Below is the updated graph.

and here is christoph’s python script.

#@Christoph Raidl(2019)
Grids = IN[0]
IsString = []
for Grid in Grids:
    try:
        name=int(Grid)
        IsString.append(False)
    except:
        IsString.append(True)
        
OUT = IsString

 

See the video below for more!

 

https://youtu.be/6_8vWdy4yzk

 

LawrenceH

Revit Tip – Back to basics, changing the sketch colour

Sometimes it’s a good thing to rewind back to basics and look at some of the things that really matter when using Revit on a day to day basis. Obviously, the interface and colours that are used and presented can make a huge difference. Below you can see the Revit 2020 Options dialog. Here you will probably notice the recent additions of ‘calculating’ and ‘Rebar Editing’.

The ‘calculating’ colour is used when working with structural connections, especially when propagate connection is used. Revit will background process the connections and display the elements with, by default, Cyan.

The Rebar Editing colour is used when editing rebar constraints, see my previous post for details on this new feature!

Anyway, back to the basics. When sketching elements such as floors or perhaps editing wall profiles we are used to seeing magenta lines as shown in the image below.

You can change this default by editing the line styles. To do this select the Manage ribbon, click Additional Settings and then Line Styles as shown in the image below.

You are then presented with the Line Styles dialog. Here you can change the Sketch colour to anything you like.

In the example below I have changed the Sketch line style to green.

This can obviously be quite useful if you have colour blindness with certain colours or are working with different background colours.

Hope this helps,

Lawrence

Revit 2020.1 Update – Rebar Constraints

Released on the 21^st August this update proves to be very useful for those using Revit for reinforcement modeling as well as some general tools to enhance usability and deliver more productivity. As always, I will not include non-structural features and just focus on the relevant tools for this sector. In this post we will focus in on the rebar constraint tools.

Rebar to Rebar Constraints

This is possibly one of the best new features for the Revit reinforcement tools for several years. The new rebar to rebar constraints allow you to set constraints between rebar objects, in previous releases it was only possible to set constraints to element faces or covers. This new command allows for much better parametric control when bar diameters are changed or when controlling lap lengths. In the image below you can see the B1 and B2 layers for a foundation. The B1 and B2 layers are constrained to the tangent faces of the rebar, if I change the rebar diameter on the B1 layer then the B2 layer and the column starter bars will automatically move! A major improvement.

In the image below you can see the beam bottom L-bars that are positioned relative to the beam top L-bars which are constrained to the Bottom and top layers in the beam. All these members are fully constrained and ‘intelligent’ and will update when members or bar diameters change.

Intuitive rebar constraints visualisation and editing

The method that you use to set rebar constraints have been improved and made more intuitive with simple icons and tooltips. Each of these can also have keyboard shortcuts assigned. The space bar will cycle through the various rebar constraints. A blue arrow now shows the positive side of the rebar which takes the guesswork away when setting offsets.

Revit Tutorial – Displaying Span to Depth Ratio of Steel Beams

In this tutorial we shall look at a method of calculating and displaying the Span to Depth ratio for steel primary and secondary beams. In early scheme design of a steel structure many engineers like to use the span to depth ratio to size members assuming a uniform loading across the beam.

Revit can be used to calculate and display the Span to Depth Ratio by creating a shared parameter and making a simple formula. Typically, a span to depth ratio of 13-15 is used for primary beams and 18-20 for secondary beams. In the following tutorial I will edit a UB family, add a shared parameter and then use the value of this and the structural usage to activate certain colours with filters. The image below shows the filters colouring, green is OK, red is over the limit and yellow is under the limit. To follow this tutorial, you will need Revit 2016 or later.

The first step is to create a shared parameter, this needs to be shared as this may need to appear in a schedule or be taggable. On the Manage Ribbon click the Shared Parameters command as shown below.

If you already have a Shared Parameter file, then click the New Parameter command as shown below. If everything is inactive, then you will need to create a new parameter file by clicking the Create button.

You will then be presented with the Parameter Properties Dialog. I am naming the new parameter SDR (Span to Depth Ratio) but you can use something else if you prefer. You will need to ensure that the new parameter is created as a Number. Click OK to both dialog boxes. Your new Shared Parameter is now ready for use.

Next you edit a Universal Beam family (or other section type for non-UK members). In the Project Browser, open the families folder and browse to Structural Framing. Below I am adding the parameter to UB-Universal Beams, but you can add this to any Section you require.

Right Click over the family and select edit. You are now in the Family Editor. On the Home Ribbon click the Family Types command as shown below

In the Family Types Dialog box click the New Parameter command as shown below.

In the Parameter Properties Dialog click the Shared Parameter radio button and then select the Select button as shown below.

Select your new SDR parameter and click OK. You now need to set the new parameter to Instance and group the parameter under Structural Analysis. Click OK. You should now see your new parameter in the Structural Analysis group.

Create the following formula. round(Length/Height)

This will take the length of the beam and divide this by the section height. Note that the section height appears under the Structural Section Geometry group. We then round this number to get a ratio value.  Save your new family and repeat for other families where you want to calculate the span to depth ratio.

Next you create a project parameter for your Span to Depth Ratio. This will enable you to create a filter. On the Manage ribbon click the Project Parameter button as shown below.

In the Project Parameter dialog, click the Add command. You will then see the Parameter Properties dialog as shown below. Configure the dialog by selecting Shared Parameter, select your SDR parameter and then click OK. Make sure that Instance is checked, group the parameter under Structural Analysis and check the category, Structural Framing. Click OK.

You now complete the last step to create a series of filters to colour the beams by their span to depth ratio. In this example you create a filter for secondary framing. You need to ensure that you have secondary framing in your project for testing. In a Project with the edited families that you have created in the steps above, open the Visibility/Graphics Override dialog and select the Filters Tab as shown below.

In the Filters tab click the Edit/New Button at the bottom of the dialog box. In the Filters Dialog box select the New command in the bottom left as shown in the image below.

In the Filter Name dialog box type Secondary Framing – Span/Depth OK.

You can now set the Category, Structural Framing and then set the AND rules to the following. ADR is greater that or equal to 18 AND SDR is less than or equal to 20 AND Structural Usage equal Purlin. Note that the Structural Usage may have differing terminology depending on the regional settings and template applied. Click OK.

You now select the Add command to add your new filter into the Visibility/Graphic Overrides Dialog.

You can then add green to override the linework and for extra impact add a solid green shade to the members. Anything that displays green is now in the correct span to depth range.

Once the filter has been set your secondary framing will appear green when the correct span to depth ratio is achieved. Note that you can create additional filters to show members that exceed and are too deep. You can also colour the SDR values in a structural framing schedule.

Hope you find this useful? I will try and create a tutorial video when I have some time.

LawrenceH