In case you ever get into one of those silly debates about the 
accuracy of C3D when labeling a pile of dirt to three decimal places, just bring this picture out. The City Traffic department in my neck of the woods laid out this round about this morning using orange traffic cones. When I inquired if a fire truck would be able to turn left through this intersection, the reply was, "We’re still working on that."
Just a friendly reminder, you can model it all you want, but do you know how it’s going to be built? Two guys with a string and some cones.
When I was child I though adults had everything figured out. Well now I am an adult and I’m wishing I had been correct.
I think the kids have it all figured out personally. Panorama and I built a model of Paris this weekend with legos. That’s all you need, really. Just legos.
I wish this was emphasized more in the civil engineering world. There can be a huge disconnect between the engineers creating the drawing, and the contractors building the project. A lot of time is wasted in modeling the perfect drawing/surface sometimes when the accuracy simply isn’t necessary because of how its being built. Good post.
Fire trucks, school buses, moving vans, they’re gonna love it! There was one similar to this in my neighborhood that the City Planning Dept. had agreed to prior to the plans getting to the Engineering Dept. It got built, 3 years later it got ripped out.
one word…AutoTurn
What ever happened to printing it full-size and laying sheets of paper on the ground? Cut on dotted line…
With response to Alan Pew…
Its not soo much about the accuracy as its about the cost analysis and the budgeting. we don’t build models in C3D and expect them to be replicated in reality. But, when the Boss says he needs a certain volume of earth and i can get it within a DEC compared to someone’s educated guess based on experience, then that means we get the contract.
bottom line.
time=money and
accuracy=more work
client=happy
i’m glad my tax-dollars aren’t going to that towns planning dept. haha.
Measure with a micrometre, mark with chalk, cut with an axe. 🙂
Didn’t you see the head lines today!
NASCAR is cutting back and this is one of their new short tracks! Just enough room for all of the campers (or should I say tent) in the infield too!
Bill N.
R. Staer said, ‘Measure with a micrometre, mark with chalk, cut with an axe.’ This raises a good question which I feel is not addressed in the civil community:
What is good enough?
As a surveyor, I am faced with this issue daily. Keep in mind that the aforementioned dirt pile was measured by a surveyor. What method did he measure the dirt pile in the first place? Most probably with a total station and a surveyor pole with a pointed tip (think how much that rod will sink into the ground). What was the density of shots that were taken to create that DTM? Now we turn over that DTM to the engineer who create civil plans that take measurements out to the n’th degree that still leaves gaps, even the ones that provide a surface model to work with, forcing the party chief to place his engineering scale on the plans and ‘scale’ stake points by hand. We have a technician in our office that is also going for his CE degree. He is learning this lesson the hard way, first-hand, by having to calculate data from inadequate plans (Not a bad idea to have EITs apprentice with surveyors, methinks). While engineers sweat decimals carried out to a bazillion decimal places, he must realize that his plans aren’t worth the paper they are printed on if they don’t provide enough information to the ‘end user’ to layout the design properly so that water will flow downhill. In other words, if the plans don’t relay the site design in a way that the surveyor pounding the blue-tops into the ground can adequately interpret, it doesn’t matter how accurate his calculations are. Gravity is a law that can’t be broken. The promise of C3D, in my opinion, is that these ‘gaps’ in design will be filled in by the surface/corridor models which can be uploaded directly into field computers, eliminating interpretation blunders. No more parking lot ponds! Just keep in mind that tools and methods we are using in the field to build your designs.
So good enough is whether the information gets translated to the grader, backhoe or level rod so that water actually does flow downhill… Not that I have an axe to grind… 😉
Andy Urban, STT
P.S. Actually, we’re high tech here. We use chainsaws to cut with.