Gain a deeper understanding of surface statistics by learning how to navigate through volume and regular surfaces in our tool space, and how to pull valuable information from the statistics tab. This comprehensive walkthrough will clarify how to use and interpret figures such as revision number, minimum and maximum coordinates, cut and fill factors, and more for a more accurate surface analysis.
Key Insights
- In surface properties, the statistics tab provides crucial information about the surface you have created, including the revision number, number of points, minimum and maximum X and Y coordinates, minimum, maximum, and mean elevation. This data can be used for a more accurate surface analysis.
- A volume surface provides essential statistics for volume, including cut and fill factors, and the amount of cut and fill needed for a grading operation. This information is crucial when determining the practicality of a site development project.
- The general statistics of a volume surface can be misleading as they are not drawn in actual coordinates. It's important to pay attention to the specifics of each statistic, like the maximum and minimum triangle lengths, to fully understand the surface's characteristics.
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In this video, we're going to talk about surface statistics. So to find out surface statistics, what we're going to go ahead and do is we're going to navigate over to our prospector tab of our tool space.
We're going to go to first our volume surface, and we're going to go ahead and right click and select surface properties. So inside of surface properties, if you navigate all the way over to the last tab under statistics, what you'll have here is information about the surface that you have created. So inside of here, what you'll notice is we have general tin and volume.
So before we dive into these, what I'm going to go ahead and do is show you the difference between a volume surface and a regular surface. We have general tin and volume. If I go to my full development surface, right click, select surface properties and go to the surfaces or the statistics tab, we have general extended and tin.
We don't have the volume like we had in the volume surface. And then in the volume surface, we don't have the extended dropdown. So I'm going to go through the volume surfaces first and under statistics, and then we'll go under the regular surfaces statistics.
Inside of surface properties, statistics tab, general, we have the options for or the information for revision number, what revision number we're at, number of points, how many points are inside of your drawing? What are your minimum X and Y coordinates? What are your maximum X and Y coordinates? What is your minimum elevation, your maximum elevation and your mean elevation? Now, this is interesting because we currently have a minimum elevation of negative 1.240 and a maximum elevation of 1.648. That doesn't make sense when we're thinking about our surface, when we were creating it off of this and our elevations that we used were 252.5 and 254.5. So the question here is what's going on with that. And the issue there is that we are comparing surfaces to each other. And you're basically setting a base elevation to compare everything off of and then comparing that surface.
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So our prop 13 surface to our full development surface, this is not being drawn in or displayed in actual coordinates. So the general information on a volume surface is very, it's incorrect. So what we're going to go ahead and do is we're going to kind of ignore these negative and very small numbers because these aren't reflective of what's actually going on our regular surfaces.
So the volume surface also has this 10 information. It gives you triangles, triangle areas, max and minimum, triangle lengths, minimum and maximum. And so these pieces of information are helpful to us.
And if we were going to try and set a maximum triangle length, if these numbers were extremely large, maybe in the realm of like 1000 feet, then we could go in here and say, okay, well, we don't want to have that long of a maximum triangle. We can choose a smaller number based on what our current maximum triangle length is. So again, in a 10 volume surface, the 10 in general are not that helpful.
A 10 volume surface, the statistics for volume is pretty much the most important thing that we're going to see here. So what we have here is we have what our base surfaces, which is full development, our comparison surface, which is prop 13. Then we have our cut and fill factors, and you can modify these later.
We had them originally when we created the surface, but you can change them if you want to go ahead and apply cut and fill factors now. So from here, we now have information on how much cut we have and how much fill we have. These are the adjusted numbers based on your cut and fill factors.
Then we have the net volume adjusted, and we have the cut and fill volumes unadjusted, and then the net volume unadjusted. We have information in here that tells us that if we did the grading operation in this property, the way that we have this drawn in, we would have 5.5 cubic yards of cut and 170.02 cubic yards of fill. And so our net grading operation would be an import or a fill of 164.52 cubic yards.
So doing a volume surface, this is the most important information you're going to pull from doing a volume surface, and this is kind of why we do volume surfaces. Moving on from there, I'm going to go ahead and hit cancel. I'm going to go to full development.
I'm going to right-click, select surface properties, and I'm going to navigate to the statistics tab and expand out general. So inside general, again, we have revision number, number of points. Now we've got a lot more points, 2,241.
We have our X and y minimum coordinates, our X and y maximum coordinates, our minimum elevation, which is 210, and our maximum elevation, which is 270.166. So these look more correct to what we were expecting because we knew that this property here was at 252 to 253. So 210,270, that makes a lot of sense. These are actual coordinates and elevations.
So these are good values to have to base surface data and information off of. We have a mean elevation. If for some reason over a certain area you wanted to obtain a mean elevation, you could do a data clip and then your mean elevation in that data clipped area would show up inside of here.
So moving on from there, we have our extended information. So this is important to know the 2D surface area of the area that you're developing, the 3D surface area, minimum grade and slope, maximum grade and slope, mean grade and slope. Oftentimes when you're doing development, you may get a municipality or somebody asking you for your minimum or maximum grade or your mean grade.
And so you can create a surface using your design elements and then go ahead and find out what your mean grade is or your maximum grade is just by going into the statistics tab. Moving on into the TIN dropdown, we have the number of triangles. We have the maximum and minimum triangle areas.
We have the minimum and maximum triangle lengths. And so what we can see here is that we have a maximum triangle length of 98.268. That is the number relative to what we
Define in here in our build operations. All of the triangles that would have been over 100 feet have now been excluded.
So our maximum triangle length of any triangle length that is under 100 feet is 98.268. So these are the surface statistics for Civil 3D. So once you close this out, we're going to go ahead and save even though we didn't make any changes. And then I will meet you in the next video and we'll talk about creating and applying spot elevations and slope labels.
