W1-13 truck rollover warning sign
W1-13 truck rollover warning sign
(OP)
How do you calculate the proper advisory speed for the truck rollover sign?
I doubt ball-banking would work, since many trucks will tip at lateral accelerations lower than 0.4, or less than it takes to cause a passenger car to skid.
Thanks!
I doubt ball-banking would work, since many trucks will tip at lateral accelerations lower than 0.4, or less than it takes to cause a passenger car to skid.
Thanks!





RE: W1-13 truck rollover warning sign
If there is a history of rollovers in a particular area, then it would seem that the speed designation exceeds the maximum design speed of the curve, for whatever reason.
KRS Services
www.krs-services.com
RE: W1-13 truck rollover warning sign
"When the Truck Rollover Warning (W1-13) sign is used, it shall be accompanied by an Advisory Speed (W13-1) plaque indicating the recommended speed for vehicles with a higher center of gravity."
It gives no guidance on how to calculate the required advisory speed.
http://mutcd.fhwa.dot.gov/HTM/2003/part2/part2c.htm#section2C11
RE: W1-13 truck rollover warning sign
Thank you for the link. This document serves as a partial regulatory function and as guideline, and accordingly, it cannot provide details such as the type of formula you are looking for, due to legal issues.
However, section 2C.02 provides your answer, sort of.
It reads:
Standard:
The use of warning signs shall be based on an engineering study or on engineering judgment.
My approach would be to evaluate the geometry of the curve and determine the speed/radius relationship. I was reviewing your question and found a neat little formula that could give you a start anyways. Give me your email address and I can scan it for you and send it to you.
The bottom line however is that the recommendation has to be substantiated by science or judgement. In my area, we have heavy industry and a huge number of vehicles are loaded tankeers, water haulers and tri-axle vac trucks. The guidlines we have used seem to work well.
KRS Services
www.krs-services.com