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Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
Professional CAD/CAM tools built on Inventor and AutoCAD
Set Clash Detective options and run a test to locate interferences in a project model.
Type:
Tutorial
Length:
5 min.
Transcript
00:03
The Clash Detective tool enables you to search through your total project model,
00:08
identifying cross-discipline interferences, or clashes, earlier in the design process.
00:14
This eliminates the manual process of inspecting and identifying clashes in a 3D project model.
00:21
Early clash detection helps to keep the construction costs down
00:25
by reducing the number of change orders caused by objects occupying the same space.
00:31
In addition to checking stationary objects in the building, you can check mobile objects, such as cranes,
00:37
to ensure that construction equipment does not collide with anything on the project site.
00:43
Here is a high-level workflow for the Clash Detective:
00:46
Start by setting the ignore clash rules.
00:49
This will help to minimize false clashes between items on the same layer, within the same block group or cell,
00:56
or items with the same snap points.
00:59
Understanding these ignore rules can make your results more meaningful.
01:04
Once you set the rules for your test, select the required items to be included in the test.
01:11
The items selected under selection A are compared against the items selected under selection B,
01:17
such as structural framing versus plumbing.
01:20
Next, use the clash settings to set the type of clash test to be run:
01:26
A Hard clash highlights objects that reside in the same space or intersect each other,
01:31
while a Hard (Conservative) clash returns objects that might clash.
01:37
With a conservative test, you can get more false positives, although it is much more thorough.
01:43
A Clearance clash test enables you to set a minimum distance between objects,
01:48
such as a water line and a sewer line that must be a certain distance away from each other for sanitary reasons.
01:55
Use the Tolerance field to set the minimum distance for the Clearance test.
02:00
A Duplicates test returns objects of the same type that reside in the same space,
02:05
making it easier to delete any duplicate items.
02:09
To run a clash test, from the Home tab, Tools panel, click Clash Detective.
02:16
The Clash Detective can be docked or floated, as needed.
02:22
Click Add Test to add a new test., then double-click the test and give it a meaningful name, such as "Plumbing versus Structure".
02:33
Next, on the Rules tab, you can indicate which rules to use.
02:39
Remember that you can have the test ignore items on the same layer, in the same group block or cell, or in the same file,
02:48
as well as items with coincidence snap points.
02:52
For this example, select all four ignore rules.
02:58
Switch to the Select tab.
03:01
Here, you select the items you want to compare against each other.
03:06
For example, in Selection A, select your structural file, and in Selection B, select your plumbing file.
03:16
Scroll down to the Settings group, and for this example, set the Type to Hard.
03:22
Click Run Test to run your selected clash test.
03:27
The Results tab automatically displays to allow you to interactively review the found clashes.
03:35
Scroll up to see a summary of how many clashes were found between the plumbing and structural members of the building.
03:43
In the Results Area, clashes are displayed in a multi-column table to enable you to locate clashes more easily.
03:52
Expand the Display Settings to enable efficient reviewing of clashes.
03:58
For example, you can change the colors displayed for Item 1 and Item 2.
04:05
If you have a cluttered model, you can use the Isolation options to dim or hide items that are not involved in the selected clash.
04:13
To review a clash in the model, select it in the results list.
04:19
Here, select Clash 5. Then, move the Clash Detective window aside to view the model.
04:28
You can see that the pipe extends through the floor.
04:33
In this case, you may need to communicate with the structural engineer to find out if this is allowable.
Video transcript
00:03
The Clash Detective tool enables you to search through your total project model,
00:08
identifying cross-discipline interferences, or clashes, earlier in the design process.
00:14
This eliminates the manual process of inspecting and identifying clashes in a 3D project model.
00:21
Early clash detection helps to keep the construction costs down
00:25
by reducing the number of change orders caused by objects occupying the same space.
00:31
In addition to checking stationary objects in the building, you can check mobile objects, such as cranes,
00:37
to ensure that construction equipment does not collide with anything on the project site.
00:43
Here is a high-level workflow for the Clash Detective:
00:46
Start by setting the ignore clash rules.
00:49
This will help to minimize false clashes between items on the same layer, within the same block group or cell,
00:56
or items with the same snap points.
00:59
Understanding these ignore rules can make your results more meaningful.
01:04
Once you set the rules for your test, select the required items to be included in the test.
01:11
The items selected under selection A are compared against the items selected under selection B,
01:17
such as structural framing versus plumbing.
01:20
Next, use the clash settings to set the type of clash test to be run:
01:26
A Hard clash highlights objects that reside in the same space or intersect each other,
01:31
while a Hard (Conservative) clash returns objects that might clash.
01:37
With a conservative test, you can get more false positives, although it is much more thorough.
01:43
A Clearance clash test enables you to set a minimum distance between objects,
01:48
such as a water line and a sewer line that must be a certain distance away from each other for sanitary reasons.
01:55
Use the Tolerance field to set the minimum distance for the Clearance test.
02:00
A Duplicates test returns objects of the same type that reside in the same space,
02:05
making it easier to delete any duplicate items.
02:09
To run a clash test, from the Home tab, Tools panel, click Clash Detective.
02:16
The Clash Detective can be docked or floated, as needed.
02:22
Click Add Test to add a new test., then double-click the test and give it a meaningful name, such as "Plumbing versus Structure".
02:33
Next, on the Rules tab, you can indicate which rules to use.
02:39
Remember that you can have the test ignore items on the same layer, in the same group block or cell, or in the same file,
02:48
as well as items with coincidence snap points.
02:52
For this example, select all four ignore rules.
02:58
Switch to the Select tab.
03:01
Here, you select the items you want to compare against each other.
03:06
For example, in Selection A, select your structural file, and in Selection B, select your plumbing file.
03:16
Scroll down to the Settings group, and for this example, set the Type to Hard.
03:22
Click Run Test to run your selected clash test.
03:27
The Results tab automatically displays to allow you to interactively review the found clashes.
03:35
Scroll up to see a summary of how many clashes were found between the plumbing and structural members of the building.
03:43
In the Results Area, clashes are displayed in a multi-column table to enable you to locate clashes more easily.
03:52
Expand the Display Settings to enable efficient reviewing of clashes.
03:58
For example, you can change the colors displayed for Item 1 and Item 2.
04:05
If you have a cluttered model, you can use the Isolation options to dim or hide items that are not involved in the selected clash.
04:13
To review a clash in the model, select it in the results list.
04:19
Here, select Clash 5. Then, move the Clash Detective window aside to view the model.
04:28
You can see that the pipe extends through the floor.
04:33
In this case, you may need to communicate with the structural engineer to find out if this is allowable.
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