Tire Performance : Tread wear and vibration of tire

Wear is an indication of the life service of the tire. At each point with in the tire footprint, there is a normal contact force and a set of tanget force. When the resultant in-plane force exceeds the friction resistances associated with the normal force at a given point, the point slips and abrasion energy is generated.

We will consider the factors that affect tire wear. More even pressure distributions reduce the number of low pressure point and minimize the likelihood of slippage. High lateral forces associated with sharp cornering increase the likelihood of slipage and thus accelerate the tread wear. Tread wear is also dependent on the road texture, tread material properties and the temperature (High temperature High tread wear). Life service of tire or tread life is defined as the travel distance at which the nonskid depth reaches a specified value. Thus, all things being equal, the nonskid should be maximized to maximize tread life. For industrial tire, life service  or tread life is defined as the working time at which the nonskid depth reaches a specified value. However, too deep a nonskid can lead to unstable tread block elements, which may result in uneven wear and poor handling performance. Driver should buy the depth gauge for measure the tire wear of his tire. A key feature of tread wear performance is the evenness of wear. Uneven wear generate noise and ride disturbances and causes additional premature wear of isolated spot on the tread surface. Tire swiching inside/outside wheel position is reduce uneven wear. In industrial tire uneven wear generate radial crack on side wall.

Tire vibration charateristics of a tire design can be computed by finite element analysis(FEA), yielding the natural frequencies and associated mode shapes in the radial, lateral, and circumferential directions. The mode shapes and natural frequencies can also be measured by rolling the tire on  drums or flat tracks and measuring the tire response. To prevent resonace, the tire's  first natural frequencies should be different from the vehicle' s naural frequencies.