A tread for a tire for a heavy-duty vehicle for mixed use and aims to improve the endurance of the crown of the tire following retention of stones in the tread. The tread (1) has voids (3) with a first, radially outer void portion (31) of groove type, having a width W11 on the tread surface (2), a width W12 at a groove bottom (311), and a depth H1, and a second, radially inner void portion (32) of sipe type, having a width W2 and a depth H2 and leading into the groove bottom (311) at a distance E with respect to the mean surface (S1) of the groove (31). The distance E is at least equal to the width W12 of the groove bottom (311) divided by 6.

Tire (1) for a heavy-duty vehicle of civil engineering type, and more particularly to the tread (2) thereof, and seeks to improve the grip thereof, while at the same time ensuring a satisfactory compromise with wearing and thermal endurance. The tread (2) comprises cuts (3, 4, 5) distributed, in a circumferential direction (XX′) of the tire, among circumferential grooves (3) and, in an axial direction (YY′) of the tire, transverse sipes (4) and transverse grooves (5), the cuts (3, 4, 5) delimiting elements in relief (6), each cut (3, 4, 5) being delimited by two faces facing one another and each face intersecting the tread surface (21) along an edge corner (311, 321; 411, 421; 511, 521). The tread (2) having a longitudinal edge corners ratio TA.sub.X equal to the ratio L.sub.X/S between the sum L.sub.X of the projections, on to the circumferential direction (XX′), of the effective edge corner lengths, contained in an elementary tread surface portion of surface area S, and the surface area S, and a transverse edge corners ratio TA.sub.Y equal to the ratio L.sub.Y/S between the sum L.sub.Y of the projections, onto the axial direction (YY′), of the effective edge corner lengths, contained in an elementary tread surface portion of surface area S, and the surface area S, the longitudinal edge corners ratio TA.sub.X is at least equal to 4 m.sup.−1 and the transverse edge corners ratio TA.sub.Y is at least equal to 6 m.sup.−1.

A pneumatic tire can suppress uneven wear of the tire and can improve traction performance on snow. Land portions (12A, 12B, 12C), between a pair of outermost side circumferential grooves (11d, 11d) on the outermost sides in the tire widthwise direction among a plurality of circumferential grooves (11a, 11b, 11c, 11d) extending in the tire circumferential direction, are divided into a plurality of blocks (14A, 14B, 14C) by widthwise grooves (13a, 13b, 13c). A pair of groove side faces (13ap, 13aq; 13bp, 13bq; 13cp, 13cq) opposed to each other in the widthwise grooves (13a, 13b, 13c) are bent at bent portions (Kp, Kq) thereof.

In a pneumatic tire, an elongation at break (EB) of carcass cords constituting a carcass layer satisfies a condition of EB≥15%. A tread portion includes a pair of center main grooves each extending in a tire circumferential direction with a tire equator line interposed therebetween, and a center land portion defined by the pair of center main grooves. A ratio (Wc/Wb) of a width (Wc) of the center land portion to a width (Wb) of a widest belt within a belt layer in the tire width direction satisfies a condition of 0.10≤Wc/Wb≤0.20. An elongation at break (EB) of the carcass cords and the ratio (Wc/Wb) of the width (Wc) of the center land portion to the width (Wb) of the widest belt satisfy a condition of 350≤10×1/(Wc/Wb)+20×EB≤900.

Commercial vehicle tire of radial design with a tread with circumferential grooves formed to a profile depth, which divide the tread into at least two profile ribs (1) running in the central region of the tread with profile blocks (2) separated from one another by transverse grooves (3) and into shoulder-side profile ribs, wherein at least one of the circumferential grooves (4) adjoining a central profile rib (1) has, in cross section, a radially outer sipe-like narrow section (6) and a channel (8) adjoining this in the interior of the tread which is configured to be wider than the sipe-like narrow section (6) and which is delimited by two channel walls (8b) and a channel bottom (8a) forming the groove bottom, and wherein this circumferential groove (4) is interrupted in its course by entry points of transverse grooves (3).

Opposite the entry points, a projection (9, 9′) is formed locally in each case on the channel wall (8b) located opposite the entry points of the transverse grooves (3).

A pneumatic tire is provided. A carcass layer includes carcass cords formed of organic fiber cords obtained by intertwining a filament bundle of organic fibers, and includes turn-up portions formed by turning up end portions of a pair of bead portions to an outer side in a tire width direction. The carcass cords have an elongation at break (EB) satisfying EB≥15%. A portion of a belt layer located in a width range of 10% of a width of a second widest belt in the belt layer on each of a left side and a right side of a tire equator line in a tire width direction has a belt angle (θc) satisfying 0.349 rad≤θc≤0.56 rad. The elongation at break (EB) of the carcass cords and the belt angle (θc) satisfy 800<1140×θc+20×EB<1400.

A tire has a tread portion whose position specified when mounted on a vehicle. An outer shoulder land region has outer shoulder axial grooves. An inner shoulder land region has inner shoulder axial grooves. The outer shoulder axial grooves include inner groove portions and outer groove portions so as to be bent convexly to one side in a tire circumferential direction. The inner shoulder axial grooves include inner groove portions and outer groove portions so as to be bent convexly to the other side in the tire circumferential direction. The inner groove portions of the inner shoulder axial grooves have an angle larger than an angle of the inner groove portions of the outer shoulder axial grooves. The outer groove portions of the inner shoulder axial grooves have an angle smaller than an angle of the outer groove portions of the outer shoulder axial grooves.

A tire includes a circumferentially continuous decoupling groove that extends radially inward toward the rotational axis of the tire. The decoupling groove is formed by inner and outer walls that are axially spaced apart from each other and joined by a base wall interconnecting inner radial portions thereof. A width between the inner and outer walls of the decoupling groove varies over a radial depth of the decoupling groove. The inner wall extends at an angle of approximately 5° from a radial plane disposed perpendicular to the rotational axis of the tire.

A pneumatic tire for heavy duty having an aspect ratio of 65% or less includes a carcass and a belt layer. A tread portion includes circumferential grooves. The circumferential grooves include a pair of shoulder circumferential grooves and a crown circumferential groove. The crown circumferential groove 11 is a narrow groove and each of the shoulder circumferential grooves is a wide groove. The belt layer includes metal belt cords inclined with respect to a tire circumferential direction. The belt layer has outer ends each positioned outside a respective one of the shoulder circumferential grooves in a tire axial direction. A belt half width is 55% or more and 85% or less of a carcass half width.

The tire has, in a tread surface, at least one circumferential groove continuously extending in a tire circumferential direction, and a shoulder land portion partitioned with the circumferential groove and a tread ground contact edge, the shoulder land portion has a first width direction groove that extends in a tire width direction and via which the circumferential groove communicates with the tread ground contact edge, the first width direction groove has, in the first width direction groove, a second width direction groove that communicates with the first width direction groove, and respective groove widths of the circumferential groove, the first width direction groove and the second width direction groove satisfy a relational expression of “the groove width of the circumferential groove>the groove width of the first width direction groove>the groove width of the second width direction groove”.