Drawing the Criteriaīelow is our area of design. 2D geometric and dimensional constraints to the rescue. But, in the real world, the existing ground will vary, the depth to the pipe will need to be adjusted, and the deflection angle will need to follow this adjustment. Now, in an “orthogonal” world, this wouldn’t be that difficult as you could simply have a block that has these deflection angles. Note though that the entrance and exit can be swapped based upon the existing conditions on either side of the road. So, looking at the diagram, we can see that the standards call for a range of deflection angles for the entrance and exit of the pipe. The diagram below shows the design standards that we must follow for this project Instead, we will propose borehole construction which will dig a hole underneath the road using a casing pipe that will carry the utility pipe. The specific example I will cover here is for constructing utilities under a major road or highway where we cannot dig a trench due to the high volume of traffic on the road. (And be sure to check out my Tuesday Tips article with an overview of 2D constraints.) Borehole Construction In this post, let’s look at a real-world example of using constraints that really saves you a good bit of time and automates a workflow that aids you in designing. I sometimes think it is because they can’t think of an everyday use for them. AutoCAD has had 2D geometric and dimensional constraints for a while, but most drafters don’t leverage their functionality in everyday use.

Autocad examples