TYRE CROWN REINFORCEMENT MADE UP OF TWO WORKING CROWN LAYERS AND A LAYER OF CIRCUMFERENTIAL REINFORCING ELEMENTS

The invention relates to a tyre (1) of the heavy-duty vehicle type which is intended to be mounted on a 15° drop centre-type hollow rim. According to the invention, the two working crown layers (41, 42) and the layer of circumferential reinforcing elements (43) are only present to form the crown reinforcement (4) over at least 40% of the width (L5) of the tread (5), 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 28+110* exp(-L/100) < α < 32+110 * exp(-L/100), and the reinforcing elements of the carcass reinforcement (2) being cords that exhibit, in the test known as the permeability test, a flow rate less than 20 cm3/min, a rubber compound being present within the cords.