A radial tire (10) for a heavy vehicle of construction plant type, and more particularly, to the sidewalls thereof (20), aims to reduce the surface cracking of the tire sidewalls and slow down the propagation of cracks in the thickness of the sidewall. The tire (10) comprises two sidewalls (20), each sidewall (20) consisting of a laminate comprising at least first and second sidewall layers (21, 22) that are axially superposed and have a total thickness E, the axially outermost first sidewall layer (21) having a thickness E1 and consisting of a elastomeric compound M1, the axially innermost second sidewall layer (22) having a thickness E2 and consisting of a second elastomeric compound M2. The thickness E1 is at most equal to 0.9 times the total thickness E, the thickness E2 is at least equal to the minimum value between 3 mm and 0.1 times the total thickness E, the first elastomer compound M1 has a number of cycles to failure NR1 at least equal to 150,000 cycles, the second elastomeric compound M2 has a number of cycles to failure NR2 at least equal to 300,000 cycles and the VP1/VP2 ratio of the respective crack propagation rates in the first and second elastomeric compounds (M1, M2) is at least equal to 1.25.

A disclosed example embodiment of a gauge wheel tire includes a first polyurethane sidewall portion, a second polyurethane sidewall portion, a polyurethane ground-engaging portion, and a polyurethane axial support portion. The first polyurethane sidewall portion is spaced apart from the second polyurethane sidewall portion, and the polyurethane ground-engaging portion extends from the first polyurethane sidewall portion to the second polyurethane sidewall portion and is adapted to contact a ground surface as the gauge wheel tire rotates about an axis of rotation. The polyurethane axial support portion extends from the first polyurethane sidewall portion to the second polyurethane sidewall portion, and is spaced apart from the polyurethane ground-engaging portion to form a gap that allows radial movement of the polyurethane ground-engaging portion relative to the polyurethane axial support portion.

A pneumatic tire includes: a bead core; a bead filler; a carcass ply; a side wall rubber that is arranged on the tire-outer-surface-side of the carcass ply and constitutes a tire outer surface; a chafer layer that is turned from the tire-inner-surface-side to the tire-outer-surface-side around the bead core and the bead filler and rolled up on an outer surface of the carcass ply; a pair of support rubbers that are located between the side wall rubber and the carcass ply and arranged so as to hold a rolled-up end of the chafer layer from both sides in a tire width direction; in which modulus values of the pair of support rubbers are higher than a modulus value of the side wall rubber, and hardness of the hardened support rubber is enhanced while scorch resistance of an unvulcanized rubber composition is maintained.

A pneumatic tire includes a pair of bead cores; a pair of bead fillers; a carcass ply that is suspended between the pair of bead cores; a side wall rubber that is arranged on a tire-outer-surface-side of the carcass ply and constitutes a tire outer surface; a chafer layer that is rolled up from a tire-inner-surface-side to the tire-outer-surface-side of the carcass ply around the bead cores and the bead fillers; and a pad rubber that is arranged between the side wall rubber and the carcass ply to be adjacent to a rolled-up end of the chafer layer in a tire width direction, the pad rubber having a modulus value higher than that of the side wall rubber. The pad rubber includes a constant thickness portion having a substantially constant thickness over a range of 7% or more but not exceeding 26% of a tire reference cross-section height.

A pneumatic tire includes a pair of bead cores; a pair of bead fillers; a carcass ply; a side wall rubber; a chafer layer that is rolled up on an outer surface of the carcass ply; and a pair of support rubbers that is located between the side wall rubber and the carcass ply and arranged such that a rolled-up end of the chafer layer is sandwiched from both sides in a tire width direction. The pair of support rubbers includes a tape rubber located inside in the tire width direction and a rear pad rubber located outside in the tire width direction. A modulus value of the tape rubber is higher than a modulus value of the side wall rubber. A modulus value of the rear pad rubber is higher than the modulus value of the tape rubber.

A pneumatic tire includes a pair of bead cores; a pair of bead fillers that are connected to the pair of bead cores; a carcass ply that is suspended between the pair of bead cores; a side wall rubber that is arranged on a tire-outer-surface-side of the carcass ply and constitutes a tire outer surface; a chafer layer that is turned from a tire-inner-surface-side to the tire-outer-surface-side around the bead cores and the bead fillers and rolled up on an outer surface of the carcass ply; and a pair of support rubbers that are located between the side wall rubber and the carcass ply and arranged so as to hold a rolled-up end of the chafer layer from both sides in a tire width direction. A modulus values of the pair of support rubbers are higher than a modulus value of the side wall rubber.

A pneumatic tire includes: a bead core; a bead filler; a carcass ply; a side wall rubber that is arranged on the tire-outer-surface-side of the carcass ply and constitutes a tire outer surface; a chafer layer that is turned from the tire-inner-surface-side to the tire-outer-surface-side around the bead core and the bead filler and rolled up on an outer surface of the carcass ply; a pair of a tape rubber and a rear pad rubber that are located between the side wall rubber and the carcass ply and arranged so as to hold a rolled-up end of the chafer layer from both sides in a tire width direction; and a tread rubber, in which modulus values of the pair of the tape rubber and the rear pad rubber are higher than a modulus value of the side wall rubber, and the tread rubber contains silica.

In a pneumatic tire, a two-dimensional code is provided on a surface of side rubber provided in a side portion. The two-dimensional code is formed of a dot pattern including two types of gray scale elements identifiably formed using surface irregularities. A two-dimensional code range in a tire radial direction in which the two-dimensional code is provided lies outward or inward of a bead filler rubber edge located outward of bead filler rubber in the tire radial direction.

A disclosed example embodiment of a gauge wheel tire includes a first polyurethane sidewall portion, a second polyurethane sidewall portion, a polyurethane ground-engaging portion, and a polyurethane axial support portion. The first polyurethane sidewall portion is spaced apart from the second polyurethane sidewall portion, and the polyurethane ground-engaging portion extends from the first polyurethane sidewall portion to the second polyurethane sidewall portion and is adapted to contact a ground surface as the gauge wheel tire rotates about an axis of rotation. The polyurethane axial support portion extends from the first polyurethane sidewall portion to the second polyurethane sidewall portion, and is spaced apart from the polyurethane ground-engaging portion to form a gap that allows radial movement of the polyurethane ground-engaging portion relative to the polyurethane axial support portion.

A heavy-duty pneumatic tire includes a section width being equal to or less than 335 mm, an aspect ratio being equal to or less than 55%, and a toroidal carcass extending between axially spaced bead portions through a tread portion and sidewall portions. The carcass includes a carcass ply which includes a main portion and a turn-up portion turned up around a bead core of each bead portion. A belt layer is disposed radially outward of the carcass in the tread portion, wherein a radially outer end of the turn-up portion is located between the main portion and the belt layer in the tread portion. A sheeted rubber layer is disposed between the main portion and the turn-up portions in each sidewall portion.