BIM and IFC models
A BIM model is a 3D model of a building or other built asset such as a bridge, road, or pipeline. BIM models are used in the planning, design, construction, and maintenance of the built asset.
Trimble Access supports the following BIM file types:
- TrimBIM (*.trb) files are BIM models in a Trimble file format that is a smaller, more efficient alternative to IFC.
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IFC files are Industry Foundation Class files. They provide a BIM model that can be used for surveying fieldwork including stakeout, cogo calculations and measuring points. Trimble Access supports IFC files in the .ifc or .ifczip file format.
Trimble Access does not support BIM models when running on an Android device.
IFC file settings in Trimble Access apply equally to TrimBIM files.
To display an IFC model in the map, tap in the map toolbar to open the Layer manager and select the Map files tab. Tap the IFC file once to make it visible (), and tap it again to make items in the file selectable (). For more information, see To manage map files.
To make only some layers visible or selectable, tap the arrow next to the file name and then tap each layer once to hide it, or twice to make it visible but not selectable. Tap the layer again to make it visible and selectable. Layers are named based on the IFCPRESENTATIONLAYERASSIGNMENT attribute in the IFC file.
To see more clearly inside a model, use the Limit box to exclude parts of the model such as floors or exterior walls. See Limit box.
Objects in IFC files can be displayed as solid objects with 100% opacity; you can reduce the opacity to make the object more transparent. To make the object more transparent, tap and select Settings. In the IFC group box, select an Opacity value less than 100%.
You can also display the model as a wireframe rather than as a solid object. Displaying as a wireframe enables you to see more detail in the IFC model and makes it easier to select the correct points or lines for stakeout. To view the model as a wireframe, tap and select Settings. In the IFC group box, select Wireframe in the Display field. If you frequently switch between wireframe and solid views, you can configure a function key on the controller to switch between the wireframe and solid view of the IFC model. For more information, see Map settings.
To rotate the BIM in the map, tap and then tap the map and drag to rotate the view. The icon in the center of the map indicates the point of orbit.
To improve performance, the map may not display very small items or details until the map is zoomed in to an appropriate zoom level.
If the controller is connected to a Trimble SX10 or SX12 scanning total station, you can view data from IFC files overlaid on the video feed. To do this, in the Video screen tap and then select Settings. In the IFC options group, enable the Overlay on video switch. To show or hide individual IFC files, or individual layers within an IFC file, tap in the Video toolbar to open the Layer manager and select the Map files tab.
As with the map, objects in IFC files can be displayed as solid objects with 100% opacity, or you can reduce the opacity to make the object more transparent. You can also choose to display the model as a wireframe rather than as a solid object.
You can select items in the IFC model from the map and then use them in other software functions, for example to perform a Cogo calculation, create a surface, or stake out. Tap an item in the IFC file to select it. You cannot drag a box around multiple items in an IFC file to select them.
You can select vertices, edges, curved edges (polyedges, such as the rim of a cylinder), grid lines, or surfaces.
To select a surface the IFC model must be shown in the map as a solid object, not as a wireframe.
You can choose whether selecting surfaces in the map selects Individual faces or selects the Whole object. To change the Surface selection mode, tap and select Settings. In the IFC group box, select your preferred option from the Surface selection mode field. See Map settings.
For example:
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When measuring to the top of a concrete slab, select the Individual faces option and then select the top surface of the slab to ensure that when measuring to the surface the software will measure only to the top surface rather than to the closest point of the whole concrete slab.
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When performing a surface inspection of a square pillar, select the Whole object option so that when you tap the pillar all 6 faces of the pillar are selected and used in the inspection.
To select all surfaces in the map, tap and hold on the map and choose Select all surfaces. Trimble Access selects every selectable surface in all BIM or IFC files that are currently set to selectable in theLayer manager. If the Surface selection mode is set to Individual faces, then each face is selected as separate surfaces. If the the Surface selection mode is set to Whole object, then all surfaces in the map are selected as a whole object surface.
To measure to a surface in an IFC model, select the surface in the map and then select Measure to selected surface from the tap and hold menu. This is useful in determining the perpendicular distance from the physical surface to the design.
To review attribute information for vertices, edges, and surfaces in an IFC file, select the items in the map and then tap Review. If you selected more than one item, select it from the list and tap Details.
To compute the center point of a surface in an IFC model, select the surface in the map and then select Compute center point from the tap and hold menu. This is useful to find the center point of a bolt or cylinder so you can then stake it out. See Compute center point.
To compute the centerline of any tube-like item in an IFC model, such as a pipe or cylinder, select it in the map and then select Compute centerline from the tap and hold menu. The software computes a polyline that runs along the center of the item. See Compute centerline.
You can stake vertices and stake them as points or select edges, curved edges, or grid lines and stake them as lines directly from IFC files.
- Tap in the map toolbar to open the Layer manager and select the Map files tab. Tap the IFC file once to make it visible (), and tap it again to make items in the file selectable ().
- Tap the items in the map to select them. You must tap each point or line in the IFC model you want to select.
- Tap Stakeout or press Enter on the controller keypad.
- To save the IFC file attributes for the selected item with the as-staked point, tap Options in the Stake out screen and set the As-staked code to Design file attributes. See As‑staked point details.
If required, you can create points from vertices in the file and save the points to the job.
- Select the vertex (or vertices) in the map.
- Tap and hold in the map and select Create point.
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For each vertex, enter the Point name.
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If required, enter the code for the point in the Code field.
- Tap Store.