Hwy design: Finding the point of need for guide rail in LD 2004

[ACtrafficengr]

I'm using (or attempting to use) Land Desktop 2004.
Looking at the cross sections, we have a 1:3 slope at Station 30+00, and a 1:1.5 slope at 30+50. Can LD find the point where the side slope exceeds 1:2, or should I generate sections every 10 feet?

This is a very low volume rural road (AADT = 300), so I don't want to waste money on rail that I don't need. After all, AASHTO has stated that rail is not usually cost effective for AADTs below 400.

Thanks!

"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

[CarlB]

Did you tell the computer to transition side slopes evenly? Then 1:2 occurs 1/3 the way between 1:3 & 1:1.5, at Sta 30+33. Look, I did that without a computer!

 

[ACtrafficengr]

The guy who generated the x-sects left for another job, so I have no idea what he did. Actually, he usually had either a cold or a hangover. I'm not sure he knew what he did!

Interpolation did occur to me, but I don't want to assume it's correct. After all, I'm the guy that will be called into court if I screw it up.

Besides, I'm a traffic engineer. I rarely do anything below the yellow paint!

"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

[lpseifert]

Generate contours for the surface, plot, get out a scale and measure between contour lines.

____________________
Acad2008, Terramodel

 

[francesca]

What is the contractor going to build from? Cross-sections? Or is there a grading plan? If the contractor only has cross-sections, then wouldn't you have to assume smooth transition? And if you have a grading plan, you can look at the contours and see if there's a smooth transition and/or figure out the slope.