Monday 9 May 2011

Create a Cellular Beam Family - A Method - Part 5 - Structural Framing Cellular Beam Family


  • Create a type catalogue txt file from the earlier created csv file. The filename must match the name of the 'Generic Model Steel Half Beam' family
  • Create a new Structural Framing Family from the 'Metric Structural Framing - Beams and Braces' template
  • Delete the elements and amend the 'Length' value to 15000 as shown
Add the following family parameters and set to instance and as a reporting parameter:
  • Section Length - (Length)
Add the following parameters from the shared parameter file and set to type:
  • Cell Pitch - (Length)
  • Cell Diameter - (Length)
  • Section Top - (Family Type : Generic Model)
  • Section Top Depth - (Length)
  • Section Btm - (Family Type : Generic Model)
  • Section Btm Depth - (Length)

  • Now load in the Steel Half UB Generic Family, selecting the required types. In this case, I've loaded every size, but you can load only the ones you need to keep down the file size. The more observant will ask 'why not make this family shared and load it from the project?'  This is a valid point, but using a shared family means you can't curve the beams. If this is not an issue, consider the shared option to optimise performance
  • In a plan view, insert a Half UB Section. Ensure 'Place on Workplane' is selected. Lock off to reference planes as shown
  • Dimension the inner end reference planes and label with the 'Section Length' parameter
  • Pick the Half UB Section. Through link the parameters as shown. Set the label to the 'Section Top' parameter
  • In a 3D view, insert another Half UB Section. Ensure 'Place on Face' is selected and pick the underside face of the web of the top section. 
  • Lock off to reference planes and through-link the parameters as per the top section. In this case however, set the label to the 'Section Btm' parameter and through-link the  'D' parameter to the 'Section Btm Depth' parameter

    I hope all this will be of help. Enjoy, and please feel free to comment with any queries





      Create a Cellular Beam Family - A Method - Part 4 - Generic Model Steel Half Beam Family

      This video shows how to create the Steel UB Half beam to be nested into the Cellular Beam Family. The main points are outlines below:



      • Create a new family from the 'Metric Generic Model' template
      • Under 'Family Category and Parameters', uncheck 'always vertical' and check 'work plane based' 
      • Add a family parameter 'Length'. Set this to instance
      • In plan, add a reference plane. Dimension the reference planes as shown and label the dimension with the 'Length' parameter. Add a round easy figure, in this case 15000. Make it fairly long, to give plenty of breathing room for the cell void array
      Add the following family parameters and set to instance:
      • Cell Run Dim - (Length)
      • Cell Qty - (Integer)
      • Cell End Dim - (Length)

      Add the following family parameter and set to instance. Add value as per the video:
      • D - (Length)(Depth of Section)
      Add the following family parameters and set to type. Add values to the parameters as per the video:
      • B - (Length) - (Width of Section)
      • T - (Length) (Flange Width)
      • t - (Length) (Web Thickness)
      • r - (Length) - (Root Radius)
      These should correspond to the parameters created in the 'Profile Steel Tee Family'


      Add the following parameters from the shared parameter file and set to instance. Add values to the parameters as per the video: (Note, the video shows type parameters for these; this was an error)
      • Cell Pitch - (Length)
      • Cell Diameter - (Length)
      Add formulas to the parameters:


      • Cell Run Dim - (Cell Pitch * Cell Qty) - Cell Pitch
      • Cell Qty - Length/Cell Pitch
      • Cell End Dim - (Length - Cell Run Dim) /2
      Next onto creating some geometry
      • Load the Profile Tee & Cell Half Void families
      • Under the project browser, click each of the loaded families above and through link the parameters as shown
      • Create a new solid sweep using the Tee profile. Lock of the sweep path as shown
      • Add symbolic lines. Set the workplane to the top flange, use the pick tool to the web lines and lock off and dimension as shown. 
      • Add a cell void to the face of the web as shown
      • In elevation, add a reference plane, dimension and label with the 'Cell End Dim' parameter
      • Align the cell void to the reference planes as shown and lock. Under the properties for the cell void, uncheck the 'visible' 
      • Pick the cell void and the reference plane as shown. Select the linear array command, check 'Group and Associate', 'Last' and 'Constrain'. label the array number dimension with the 'Cell Qty' parameter
      • Dimension the reference planes in the first and last groups of the array. Label this with the 'Cell Run Dim' parameter

      Create a Cellular Beam Family - A Method - Part 3 - Generic Model Cell Void

      The next video outlines the creation of the void cut that will be nested in the Half Beam family. The stages are as follows:


      • Create a new family from the 'Metric Generic Model Face Based' template
      • From the shared parameter file created earlier, add 'Cell Diameter' and make it a type parameter. Also, add a family parameter 'Void Depth', also a type parameter
      • In plan, add a semi-circle void extrusion and dimension as shown. Set the dimension to the 'Cell Diameter' parameter
      • In section, create a reference plane below the level mark. Drag the shape handles of the void to the level and the reference plane and lock off. Dimension the reference plane from the level and set to the 'Void Depth' parameter
      • Now cut the extrusion to the void using the 'Cut' command

      Create a Cellular Beam Family - A Method - Part 2 - Profile Tee Family

      Profile Tee Family
      This is required for the the Half Beam Sections. The following video shows how to put it together. Start from the 'Metric Profile' template



      Create a Cellular Beam Family - A Method - Part 1 - Shared Parameters & Catalogue

      Shared Parameters






      Create Shared Parameters as follows (parameter type shown in brackets):
      • Cell Pitch (Length)
      • Cell Diameter (Length)
      • Section Top (Family Type : Generic Model)
      • Section Top Depth (Length)
      • Section Btm (Family Type : Generic Model)
      • Section Btm Depth (Length)


        Catalogue

        The cellular beam family here will be composed of sections from UK steel stock, UB (Universal Beam) sections and a catalogue of sizes will be required. At Waterman, we create our standard catalogues from scratch, using compiled information from the Tata/Corus Online 'Blue Book'. and extra parameter that we use (as opposed to the OOTB catalogues). These master catalogues are held as csv files, then copied and renamed to the appropriate family type catalogue txt file. For information on creating type catalogues, refer to the Revit help files. The type catalogue will drive parameters in the 'Generic Model Steel Half Beam Family'

        Create a Cellular Beam Family - A Method - Overview

        A few weeks ago, Glenn Jowett posted on his RevitST blog about the OOTB Cellular Beam Family.
        I completely echo Glenn's sentiments and it reminded me of the issues we have had. We have had a workable alternative for some time, but it needed a little more development, which Glenn's post has prompted me to do something about. Also, that we should share this with the larger Revit community. The issues have been to get something that is both user friendly and has good model performance. Autodesk recommend economy when using voids, arrays and nesting in families, which unfortunately are required for this particular family to work.  I will cover the aspects in different parts as outlined in the shopping list below to keep it manageable:


        Brief


        Create a cellular beam family. End user parameters to be limited to the Cell Pitch/Diameter and the section size top and bottom. Model performance must be managed in the right way


        Shopping List

        • Shared Parameters
        • Catalogue of Standard Sizes
        • Profile Steel Tee Family
        • Generic Model Cell Void Family
        • Generic Model Steel Half Beam Family
        • Structural Framing Cellular Beam Family