In a pneumatic tire including a carcass layer mounted between a pair of bead portions and a belt reinforcing layer disposed on an outer circumferential side of the carcass layer, the carcass layer is formed of a carcass cord made of an organic fiber cord, an elongation at break of the carcass cord is set to 20% or more, an elongation under a load of 1.5 cN/dtex of the carcass cord in sidewall portions is set to from 5.0% to 8.0%, the belt reinforcing layer is formed of a cover cord made of an organic fiber cord, and a tensile strength of the cover cord per width of 50 mm at a 3.0% elongation is set to from 2.8 kN to 4.0 kN.

In a pneumatic tire including a carcass layer mounted between a pair of bead portions and a belt reinforcing layer disposed on an outer circumferential side of the carcass layer, the carcass layer is formed of a carcass cord made of an organic fiber cord, an elongation at break of the carcass cord is set to 20% or more, an elongation under a load of 1.5 cN/dtex of the carcass cord on the inner circumferential side of the belt layers is set to from 5.5% to 8.5%, the belt reinforcing layer is formed of a cover cord made of an organic fiber cord, and a tensile strength of the cover cord per width of 50 mm at a 3.0% elongation is set to from 2.8 kN to 4.0 kN.

A tire for an agricultural vehicle (1), and in particular the carcass reinforcement (4) thereof, for a tire running at low pressure on loose ground, is to reduce the compaction of the ground and to increase the traction capability by reducing the structural stiffness of the tire. According to the invention, the carcass reinforcement (4) is made up of a single carcass layer (41) having a mean thickness E at most equal to 2 mm and a breaking strength Fr, expressed in daN/cm, that satisfies the relationship:

Fr>=Fs=(Cs*Pmax*10.sup.−3)*((R.sup.2−((R+Rj)/2).sup.2)/2)/Rj, with Fs: reference threshold strength (in daN/cm) Cs: safety factor at least equal to 1, Pmax: recommended maximum inflation pressure (in kPa), R=D/2: outside radius of the tire (in mm), Rj=Dj/2: nominal radius of the rim (in mm).

A tire for an agricultural vehicle (1), and in particular the carcass reinforcement (4) thereof, for a tire running at low pressure on loose ground, is to reduce the compaction of the ground and to increase the traction capability by reducing the structural stiffness of the tire. According to the invention, the carcass reinforcement (4) is made up of a single carcass layer (41) having a mean thickness E at most equal to 2 mm and a breaking strength Fr, expressed in daN/cm, that satisfies the relationship:

Fr>=Fs=(Cs*Pmax*10.sup.−3)*((R.sup.2−((R+Rj)/2).sup.2)/2)/Rj, with Fs: reference threshold strength (in daN/cm) Cs: safety factor at least equal to 1, Pmax: recommended maximum inflation pressure (in kPa), R=D/2: outside radius of the tire (in mm), Rj=Dj/2: nominal radius of the rim (in mm).

A tire having a radial carcass reinforcement, made up of a single layer of reinforcing elements anchored in each of the beads by being turned up around a bead wire, reinforced by a stiffener. The two working crown layers are the only ones present to form the crown reinforcement over at least 75% of the width of the tread, the absolute value of the difference between the absolute values of the angles α2 and α1 being greater than 7°, α2 being greater than α1 in terms of absolute value, the mean angle α satisfying the relationship 13+131*exp(−L/100)<α<28+110*exp(−L/100), the reinforcing elements of the carcass reinforcement being cords which, in the test referred to as the permeability test, yield a flow rate of less than 20 cm.sup.3/min, a rubber compound being present within the cords, and, in the sidewall of the tire, the profile of the outer surface of the tire is at a constant distance from the carcass reinforcement layer between the points F and A, and meets the outer surface of the bead at the point C, forming two successive circular arcs.

A tire having a radial carcass reinforcement, made up of a single layer of reinforcing elements anchored in each of the beads by being turned up around a bead wire, reinforced by a stiffener. The two working crown layers are the only ones present to form the crown reinforcement over at least 75% of the width of the tread, the absolute value of the difference between the absolute values of the angles α2 and α1 being greater than 7°, α2 being greater than α1 in terms of absolute value, the mean angle α satisfying the relationship 13+131*exp(−L/100)<α<28+110*exp(−L/100), the reinforcing elements of the carcass reinforcement being cords which, in the test referred to as the permeability test, yield a flow rate of less than 20 cm.sup.3/min, a rubber compound being present within the cords, and, in the sidewall of the tire, the profile of the outer surface of the tire is at a constant distance from the carcass reinforcement layer between the points F and A, and meets the outer surface of the bead at the point C, forming two successive circular arcs.

A tire design for a heavy-duty vehicle of construction plant type has a crown reinforcement (40) radially on the inside of a tread (10) and radially on the outside of a carcass reinforcement (70). The carcass reinforcement (70) has at least two carcass layers (50, 60) having metal reinforcers coated in an elastomer compound. The carcass layers (50, 60) have respective stiffnesses per unit width R1, R2. Metal reinforcers of a first carcass layer (50) form, with the circumferential direction (XX′), an angle A1, and those of the second carcass layer form an angle A2, such that the angles A1 and A2, and the stiffnesses R1 and R2, simultaneously satisfy the following three relationships: R1*sin 2(2*A1)+R2*sin 2(2*A2)≥(R1+R2)*) sin 2(30°), and ∥A1|-|A2∥<10°, and 0.7≤R1/R2≤1.3. The metal reinforcers have a critical compression buckling deformation DF at least equal to 2.5% and a compression elastic modulus MC at least equal to 10 GPa.

A pneumatic tire may have an outboard bead portion oriented on an outboard side of the tire, an inboard bead portion oriented on an inboard side of the tire, an outboard sidewall portion oriented on the outboard side of the tire, an inboard sidewall portion oriented on the inboard side of the tire, an outboard shoulder portion oriented on the outboard side of the tire, and at least one body ply. The body ply may extend about the outboard bead portion and have a first turnup that extends to at least the outboard shoulder portion. The body ply may extend about the inboard bead portion and have a second turnup that extends to, and terminates in, the inboard bead portion or the inboard sidewall portion, wherein the first turnup height is greater than the second turnup height. At least one belt may be oriented radially outward of the body ply.

Provided is a pneumatic tire enabling improvement of side cut resistance and suppression of increase in mass. A pneumatic tire 1 includes: a tread portion 2; a pair of sidewall portions 3; a pair of bead portions 4 having respective bead cores 5 embedded therein; and a toroidal carcass 6 disposed between the pair of bead portions 4. The carcass 6 includes a first ply 11 extending on and between the pair of bead portions 4, and a second ply 12 disposed, in the tread portion 2, outward of the first ply 11 in a tire radial direction and extending on and between the pair of bead portions 4. The first ply 11 is formed as a layer of first cords. The second ply 12 is formed as a layer of second cords. A thickness of each second cord is 1.1 to 2.0 times a thickness of each first cord.

The present invention is provided with: a mounting body mounted on an axle; a ring-shaped body (13) surrounding the mounting body from an outside in a tire radial direction; a connecting member (15) configured to connect the mounting body and the ring-shaped body (13) such that the mounting body and the ring-shaped body (13) are displaceable; and a cylindrical tread member (16) mounted over the ring-shaped body (13), wherein grooves (51, 52) are formed at an outer peripheral surface of a portion located above and corresponding to a portion of the tread member (16) at which the ring-shaped body (13) and the connecting member (15) are connected.