in australia they have really big ones running the edges of the toll ways.. and some highways.. i remember back in the day driving my ex girlfrends Datsun over the marks and it felt like the car was goin to fall apart. heheh.. pati yata mga truck and bus nag vibrate enough to shake the driver awake..
Nagsulputan yang mga rumble strips na yan kung saan saan. Some are not even up to standard, they are supposed to make the vehicle vibrate mo or sound louder if the car is travelling fast, and not actually feel it if the car is slow. Pero karamihan baliktad, nanginginig the whole car if mabagal and wala kang maramdaman if mabilis.