Pavement Marking

[DaBigE]

For a standard, broken line (lane or center line), WisDOT uses a 50-ft cycle based on a 12.5-ft dash with a 37.5-ft skip.  Does anyone know the history behind that decision, (or at least some sound logic to explain it)?  I brought it up in a discussion with the State marking engineer when other lane line cycles were being updated a while back, and she had no idea of the reasoning, nor why it has never been changed to an even number like all the rest of WisDOT's marking styles are (3|9, 1|4, 6|3, etc).  Maybe it's just me, but I find ending with a 0.5 to be strange.

[NE2]

Huh? That's a 3:1 ratio.

[DaBigE]

Huh? That's a 3:1 ratio.

Yes, which matches what the MUTCD prescribes

Guidance:
04 Broken lines should consist of 10-foot line segments and 30-foot gaps, or dimensions in a similar ratio of line
segments to gaps as appropriate for traffic speeds and need for delineation.

But why end on a 0.5?  Maybe it's just me, but it seems awkward when you could end in a "round" number like 10|30 or 15|45 or since the MUTCD says similar ratio, why not 12|38 or 13|37?

[NE2]

But why end on a 0.5?  Maybe it's just me, but it seems awkward when you could end in a "round" number like 10|30 or 15|45

Who knows? They started with 50 and went from there.

or since the MUTCD says similar ratio, why not 12|38 or 13|37?

Because they wanted 3:1, not something weird like 17:6.

[agentsteel53]

But why end on a 0.5? 

because 50 is not divisible by 4.

more generally, because the human-preferred number "10" is not divisible by 4.

[Alps]

It's more a question of "why doesn't Wisconsin get with everyone else and go with 30/10?" Similar to "why do the NJ Turnpike and ISHTA roads still use 25/25?"