B60C2009/1842

Optimized architecture of a civil engineering tire

A tire (1) for a vehicle of the construction plant type, having a carcass reinforcement (4) and a crown reinforcement (3), with at least five crown layers (311, 312, 321, 322, 331, 332) having metal reinforcers. The protective layer (312) has elastic reinforcers having a tensile modulus at most equal to 110 GPa. The rubbers, referred to as crown decoupling rubbers (6), that are located around the axial ends of the crown layers (311, 312, 321, 322, 331, 332) have an elongation at break at least equal to 500%, and a dynamic loss tan at most equal to 0.06. A crown filler rubber (5) between the axial end of the axially widest working layer (321) and the carcass reinforcement (4) possibly has an elongation at break at least equal to 650% and a dynamic loss tan, at 100 C. at 10 Hz, at most equal to 0.07.

TIRE WITH PLY STRIP BELT

A tire is disclosed having at least one belt formed by ply strips. The ply strips preferably have a first end that are staggered from each other, and more preferably are staggered in equal increments. Each ply strip comprises an elastomer composition reinforced by at least one elongated reinforcement element. In one aspect, each ply strip has an angle with a circumferential direction within a range of 6 to 14. In another aspect, each ply strip has an angle of at most 15 with the circumferential direction, and at least one strip end of each ply strip is located at one lateral edge of its belts. In another aspect, a belt is formed by at least three ply strips, each ply strip being spirally wound about an axis of rotation of the tire, and having a first strip end located at a first lateral side of its belt.