Discover the process of conducting a more advanced clash test including clash batching using the BIM361 model. This guide walks you through setting up and running multiple clash tests in projects using Navisworks, and how to effectively interpret and manage the results to improve your building design.
Key Insights
- The process involves setting up clash tests between different trades like structural versus plumbing, structural versus mechanical, etc., and then running these tests all at once using the 'update all' function.
- Despite initial large numbers of clashes, many of these are duplicates due to composite objects and repetition in structures. Therefore, a closer review of the clash results can often significantly reduce the number of actual issues.
- The practice of clash batching helps to manage large numbers of clashes by grouping them together and marking them as either approved or resolved, making it easier for team members to address and resolve issues efficiently.
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Welcome back to the Navisworks video series. In this video, we'll be covering a more advanced clash test, including clash batching, and we'll be using the BIM361 model complete. Currently, it’s saved in the Lesson 3 folder. Go ahead and open the bim361complete.nwf file, and we'll immediately save this file in Lesson 6. Go to Save As in the application menu, navigate up to Lesson 6, and we'll save it as the same file name.
This will create a checkpoint for us and will allow us to keep working on this more advanced clash model. Make sure your Clash Detective is open. If you don't see the panel, turn on Clash Detective from the Home tab, and then make sure it is open and pinned.
We currently have no clash tests defined for this project. We need to add a test. Let's call this test Structural versus Plumbing.
We'll use the abbreviation stru v plum. I use short abbreviations for my clash batch names because I find that when they're short enough in the clash test, you can easily read them. They don't get truncated, and they also correspond with the file naming system we've already created for our projects.
So, for the Structural versus Plumbing test, Selection A is going to be the structural file, and Selection B will be the plumbing file. That's everything that's in structural versus everything in plumbing. Now, we can run this clash test now, or we can create a new clash batch, which is what we’ll be doing.
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We'll be making a batch for every one of the trade combinations. So let's go to Add Test again. This test will be Structural versus Mechanical, going straight down the list.
Structural versus Mechanical. Let's add another test, rename this one.
Call it Structural versus Electrical, and that will be Structural versus Electrical. Well, let's add another test: Plumbing versus Mechanical. Plumbing and Mechanical, and then Plumbing v Elect—that's Plumbing versus Electrical. And then I added another test.
You might have to scroll down to see the new test you created. This is Mechanical versus Electrical. Mechanical versus Electrical, and I think that covers all the trades. Now, let's go through the list one by one and see if they're all set correctly.
Structural versus Plumbing, Structural versus Mechanical, Structural versus Electrical, Plumbing versus Mechanical, Plumbing versus Electrical, and Mechanical versus Electrical. Great! Let’s run all these clash tests by hitting Update All, and that runs them all for us at once.
We don't have to go individually and hit Run Tests on each batch. Now, we can see how many clashes are in each of our clash tests. Structural versus Plumbing, Structural versus Mechanical, Structural versus Electrical is 325.
Plumbing versus Mechanical is 231. Plumbing versus Electrical is one. Now, these may seem like large numbers, and they are, indeed, large numbers.
Don’t let the first numbers fool or scare you too much. Most of these clashes are duplicates. This is because there are composite objects that have, like, for example, the lights we saw in the last video, that have more than one piece of geometry that make them up.
Mechanical has quite a few components within one object. And versus structural—sometimes there are so many components that repeat, like joists, that if a duct line hits one joist, it's likely to hit many others in the same line. So, let’s take a look at the first test, Structural versus Plumbing, and let’s go to the results and see what it looks like.
What I like to do first is to check “Highlight All Clashes” and make sure “Dim Other” and “Transparent Dimming” are both on. Change the viewpoint to manual, and I like to hit the Home button and then take a quick run through the project to see where most of the problems are occurring. I see some bracing versus piping.
I see a lot of slab penetrations. Yeah, there’s steel versus pipe, and then there are some big problems there. This looks like a slab versus a toilet.
So, a lot of these clashes are common. Most floors have the toilets scraping against the slabs, and a lot of the penetration problems are generally acceptable because a lot of structural engineers don't model the holes in the slabs. Because if we move this pipe a little bit, they would have to update their holes every single time. So, a quick overview is always an important, useful way to see where you stand in your model.
So, the 161 is probably going to be reduced to something like 20. And when I say reduce, I mean that we can reduce the number of clashes that show in this number by grouping them together and by marking them as either approved or resolved. Sometimes we can set "Reviewed" to mean that it's okay even though it's not approved or resolved. I was going to cover clash grouping during this video, but I decided that was a topic deserving of its own video.
So, for now, we should just go through each of our tests and go through a general overview so we know what to expect when we start to clash group. This is the Structural versus Mechanical clash test. It looks like we have a number of common clashes.
This duct line directly conflicts with a lot of structural. So, resolving that one line may take care of a few hundred clashes. The same goes for many of the other ducts.
Structural versus Electrical. It looks like we have some cable tray issues. Looks like it’s mostly cable trays, actually.
Plumbing versus Mechanical. We have some pipes penetrating ducts. Plumbing versus Electrical.
We have one, and that looks like a pipe versus cable tray. And then Mechanical versus Electrical. It looks like mostly cable trays versus ducts.
And there’s a light in the ducts. But that is clash batching, and the upcoming videos will cover how to set status and assign clashes to specific trades, as well as how to group clashes to reduce the number of clashes that are showing, and to give your team members fewer than 1,700 clashes for Structural versus Mechanical—in little pieces that they can actually handle much more easily. That concludes this video.
I hope you enjoyed it, and I’ll see you in the next video. Thank you.