Patent ID: 8170839

Claim:
A method of designing a tire, the method comprising: modeling a tire design that includes a tire tread with a plurality of circumferential ribs having a plurality of lugs and a plurality of circumferential continuous grooves, including at least two circumferential ribs that are laterally unlocked from each other by an adjacent circumferentially continuous groove; modeling a lug having a specific length in each of the plurality of circumferential ribs and determining a circumferential shear stiffness for the lug in each of the plurality of circumferential ribs; determining a circumferential shear stiffness per unit length for each of the plurality of circumferential ribs; selecting a reference rib, wherein the reference rib has a reference number of lugs; modeling the plurality of circumferential ribs calculating an ideal number of lugs for each of the plurality of circumferential ribs; calculating an optimum number of lugs for each of the plurality of circumferential ribs by rounding the ideal number of lugs to a nearest integer; and modifying the tire design to include the optimum number of lugs determined for each of the plurality of circumferential ribs.