TIRE TRACKS

Track vs. Tread

• Tire Track: path left in the soil by the wheels of a vehicle

• Tire Tread: pattern of tread design on tire

Tracks

• Tracks can be used to indicate:– Direction of travel– Change in direction– Tread wear pattern

Direction and Change of Travel

and moved toward point 2

This vehicle began at point 1

The vehicle stopped and backed up to point 3

The vehicle stopped at point 3 and then moved forward to point 4

Tire Tread Patterns

• Records are kept of different tire tread patterns so that tires can be traced to different sizes of tires and often different makes and models of vehicles

Preserving Tracks

• Photograph the track first!! If a cast cannot be made, photographs will be very important

• Make sure to use a scale that will show in the photographs

• Dental stone is used to make a cast• If a track is in snow, a special wax is

used to make the track hard enough to cast

Measuring Tracks• Tracks must be measured• Tire Track Width: distance in inches between

the middle of the two front tires or the two back tires

• Tire track width is used to identify the type of vehicle

Measuring Tracks

• Tread width: distance in inches across the tread pattern

• Tread widths should be measured on both the front and back tires since some vehicles may use different tires