Pneumatic tire having improved wear properties

A radial ply pneumatic automobile tire for use on paved surfaces comprising a pair of annular beads, carcass plies wrapped around said annular beads, a tread disposed over said carcass plies in a crown area of said tire, and sidewalls disposed between said tread and said beads, wherein said tire has an aspect ratio of 0.35 to 0.80 and said tread has a footprint net-to-gross ratio of 40% to 70% and at least one annular center groove having a width of about 10% to 25% of total tread width based on the footprint of the tire at standard inflation and standard load, said annular center groove having a depth of 78% to 100% of total tread depth and a curvate U-shape, and lateral grooves intersecting circumferential grooves between said annular center groove and a shoulder, intersections of the circumferential grooves and the lateral grooves defining lugs wherein said lugs are traversed by sipes which improve traction and contain tie bars which stabilize the lug, and wherein an angle .alpha. of principle lug stiffness in each shoulder lug is .+-.80.degree. to 90.degree. in the top 25% of the lug with respect to the equatorial plane of the tire, and wherein the circumferential length of lug segments in all the lugs are within 55% of each other, lugs (18) comprise a leading portion (37) and a trailing portion (39) which are separated laterally by a sipe (17) and wherein said sipe (17) changes direction in each lug at least twice so that in one circumferential edge (42) each lug has a leading portion which is wider than its concurrent trailing portion, and in the other circumferential edge (43) of the lug, the trailing portion is wider than the leading portion, and wherein the ratio of a radius of curvature at the edge of the tread corresponding to the edge of the footprint to a radius of curvature at the centerline of the tire is 0.024/1 to 0.044/1.