Corridor Construction Simulation for BIM Managers
Introduction
Most BIM Managers recognize that Building Information Modeling (BIM) is not a specific software program. It is a streamlined process that allows us to make better decisions about project designs based on reliable information analysis. Part of that analysis can include creating a construction simulation to see how everything will fit together during the construction phase of the project. This helps engineers better predict a project’s performance to increase safety, constructability, and sustainability before it is built; thus facilitating better decision making and more economic project delivery. In this article, I share what the BIM Manager needs to do to set up the AutoCAD® Civil 3D corridor model for a construction simulation using Autodesk Navisworks® TimeLiner.
In AutoCAD Civil 3D, multiple parts make up one road corridor in the model, as shown in Figure 1. During construction, the entire road would not be built all at once. First, grading would be done to set the datum elevation for the site. Then the sub-base and base would be laid down. Next the sidewalks and curb & gutter would be poured. Finally, the asphalt or concrete would be poured for the wearing course of the road.
Figure 1: Corridor parts
Preparing the Model in AutoCAD Civil 3D
When creating a construction animation using Timeliner, you can create the simulation to match a real construction schedule. To do this, you must separate the corridor model into parts in AutoCAD Civil 3D before taking the model into Navisworks. By creating separate parts for each material (sub-base, base, sidewalk, etc.), you can show the road being constructed one layer at a time—just like it would be during construction. It also allows you to break it up into specific lengths to match how much the construction crew will work on each day.
When converting a corridor to solids, it is important that the Layer Name Template match the task names in the project management database, as shown in Figure 2. This makes it much easier later to link objects in the model to the construction schedule.
Figure 2: Corridor solid layer names to match PM task names
Figure 3: Extract Corridor Solids dialog box
How To: Extract Corridor Solids
- In AutoCAD Civil 3D, select the corridor.
- In the Corridor contextual tab>Corridor Tools panel, click
(Extract Corridor Solids). - In the model, select the regions for only the area you wish to extract. Options include:
- Station range: Has you first select a region, then you are prompted to specify the start station. You can use the mouse to select it or you can type a start station in the command line. After setting the start station, you are prompted to set the end station.
- Within Polygon: Allows you to select a previously created polygon.
- All regions: Selects the entire corridor model.
4. In the Create Solids From Corridor dialog box, make sure the Layer Name Template matches the item names in the project management task list.
- In the Name Template column, click
(Modify Name Template) next to the Baseline, as shown in Figure 3. - Selecting the Name template for the Baseline ensures that all the regions are updated to the new Name Template.
- You must do this for each baseline listed in the Extract Corridor Solids dialog box.
5. In the Name Template dialog box, do the following, as shown in Figure 4:
- Select Construction Region Name in the Property fields drop-down.
- In the Name field, highlight everything, then click Insert.
- Select Codes in the Property fields drop-down.
- In the Name field, place your cursor at the end, click Insert.
- Click OK.
Figure 4: Name Template dialog box
6. In the Create Solids From Corridor dialog box, click Next twice.
7. In the Create Solids From Corridor dialog box>Output Options page (shown in Figure 5), make sure that AutoCAD 3D Solids (based on corridor sampling) is selected from the drop-down list. Then select where you would like the solids stored. Choices include:
- Insert into current drawing (recommended if you already have a Navisworks model created that includes the Civil 3D road model)
- Add to an existing drawing
- Add to a new drawing
8. Click Extract Solids.
Figure 5: Extract Corridor Solids output options
Results
If you already have a Naviswork model created with the AutoCAD Civil 3D model appended, and you selected the option to Insert the corridor solids into the current drawing, as shown in Figure 5, then all you need to do is refresh the Navisworks model. The result of all this is that each of the corridor solids become its own layer. In Navisworks each solid is listed by layer in the Selection tree, as shown in Figure 6.
Figure 6: Corridor solid layers
Populate the Project Management Task List
All that is left for you to do is make sure that the project management software you are using lists tasks for each corridor solid. One very fast way to do this follows.
How To: Populate the Task List and Ensure a Perfect Match
- Open the AutoCAD Civil 3D Layer Properties Manager.
- Select all the layers that contain corridor region names. (Hold down <Ctrl> or <Shift> as necessary to select more than one.)
- On the keyboard, press <Ctrl> + C to copy the layers to the clipboard.
- Open Microsoft Excel or another spreadsheet program; put your cursor in one cell.
- On the keyboard, press <Ctrl> + V to paste the layer information into the spreadsheet from the clipboard. You should end up with something like what is shown in Figure 7.
- Clean up the columns, then port the layer names into your Project Management database as task names.
- Add the start and end dates for each task—per when each corridor structure will be constructed on the project site.
Figure 7: AutoCAD Civil 3D layers copied into a spreadsheet
Tips in Navisworks
After you bring the project management task list into the Navisworks TimeLiner, you can automatically link the corridor solids to the tasks. This is done in two easy steps.
How To: Link the Task List to Corridor Solids Automatically
- 1.In the TimeLiner>Tasks tab, click
(Auto-Attach Using Rules). - 2.In the TimeLiner Rules dialog box, select only the last rule Map TimeLiner Tasks from Column Name to Layers with the same name, Matching case and click Apply Rules, as shown in Figure 8.
Figure 8: TimeLiner Rules dialog box
Conclusion
When it is all said and done, you are able to simulate the road corridor being built. If there are buildings going in at the same time as the road, you can also add that schedule to the simulation, as shown in Figure 9. Additionally, you can link TimeLiner and Animator inside Navisworks to see how all the different pieces of construction equipment move around the site to ensure each has ample room to complete its tasks.
Figure 9: Simulation in progress
Michelle Rasmussen started in the Air Force working in the Civil Engineering unit as a surveyor, designer, and construction manager in the early 1990’s. She has worked for both municipalities and consulting engineering firms as an engineering/GIS technician where she completed transportation studies, environmental impact studies, and drafted subdivision and site plans. She has been training people on Autodesk products since 2000 and is currently an author for ASCENT (ascented.com) where she writes books for Autodesk infrastructure software products such as AutoCAD Civil 3D, Autodesk InfraWorks 360, AutoCAD Map 3D, Autodesk Navisworks, and general AutoCAD.
