Wednesday, December 9, 2009

accident on road

Greetings to all of you,

this time , we compare accident frequencies
per location and rates per truck VMT by ramp
type, conflict area, and accident type so as to reveal
location, volume, and travel distance effects. This
required that we estimate ramp truck ADT for
ramps where it was not recorded, which we convert
to ramp truck VMT for the full study period.
WSDOT provided us with ADT and truck percentages
at 123 on-ramps and 123 off-ramps. We
fitted relationships of RTADT to ramp ADT of all
vehicles (RADT) at 84 ramps with at least one
truck accident during the study period. Figure 3
shows estimated versus observed RTADT for onramps.
The figure for off-ramps is very similar


Truck Accident
Semi Truck Accident