A tire includes a tread portion being provided with a pair of circumferentially and continuously extending shoulder main grooves and at least one crown main groove between the shoulder main grooves to form a pair of middle portions each of which is between adjacent one crown main groove and one shoulder main groove. Each of the middle portions is provided with a circumferentially and continuously extending longitudinal sipe, a plurality of inner middle sipes extending axially outwardly from the crown main groove and terminating without reaching the longitudinal sipe and a plurality of outer middle sipe extending axially inwardly from the shoulder main groove and terminating without reaching the longitudinal sipe. The number of the outer middle sipes is greater than the number of the inner middle sipes.

A tire has, on a tread surface of the tire, five land portions, an installation direction of the tire to a vehicle is designated, intermediate land portions respectively have a communicating sipe 40, the communicating sipe is constituted by a first sipe 41 at a vehicle-installed outside and a second sipe 42 at a vehicle-installed inside, the first sipe and the second sipe have an intersection point P on the vehicle-installed outside of a center line in a tire width direction of the corresponding intermediate land portion, the distance between the intersection point and a land portion edge at the vehicle-installed inside is the largest in an innermost intermediate land portion of the intermediate land portions, and an angle 1 of the first sipe to a tire circumferential direction is larger than an angle 2 of the second sipe to the tire circumferential direction.

An intermediate rib has a plurality of intermediate sipes arranged at a predetermined pitch in a tire-circumferential direction and extending in a direction intersecting the tire-circumferential direction, the intermediate sipes include a plurality of first intermediate sipes on one side in a tire-width direction and a plurality of second intermediate sipes on another side in the tire-width direction, the first intermediate sipes and second intermediate sipes are alternately arranged in the tire-circumferential direction, a width of the center rib has a size which is at least 104% of the width of the intermediate rib, a pair of the intermediate sipes adjacent in the tire-circumferential direction have overlap parts which overlap each other when viewed in the tire-circumferential direction, and a tire-width direction length of this overlap part is at least 30% of the width of the intermediate rib.

In the pneumatic tire according to this disclosure, a plurality of sipes on a tread surface include a large intermediate width sipe 4 having: a pair of intermediate sipe wall surface portions 61, a pair of bottom-side sipe wall surface portions 62 and a pair of tread-surface-side sipe wall surface portions 63; and within a central region of the tread surface, a spacing along a tire circumferential direction between the large intermediate width sipe and another sipe or groove is 2.0 to 4.0 times of a sipe depth D of the large intermediate width sipe.

Tires comprising a hoop reinforcement (5) and 2 crossed working layers (41, 42) in which the breaking strength R.sub.C of each working layer (41, 42) is at least equal to 30 000 N/dm have improved endurance. The working layers comprise reinforcing elements made up of individual metal threads or monofilaments having a cross section at least equal to 0.20 mm and at most equal to 0.5 mm. The density of reinforcing elements in each working layer is at least equal to 100 threads per dm and at most equal to 200 threads per dm. The tire also comprises axially exterior cuts (25). At least one of the two axially exterior portions of the tread comprises a rubbery material having a Shore hardness at least equal to 48 and at most equal to 60.

A tire comprises a tread portion 2 having an outboard tread edge To and an inboard tread edge Ti and provided with an outboard shoulder main groove 3 and an outboard crown main groove 4 extending continuously in the tire circumferential direction so as to define an outboard middle land region 10 therebetween. The outboard middle land region 10 comprises outboard middle blocks 17 circumferentially divided by outboard middle lateral grooves 16. Each of the outboard middle blocks 17 is provided with outboard middle sipes 20 extending zigzag in the tire axial direction, wherein each of the outboard middle sipes 20 has an axially outer end terminated within the outboard middle block 17, and the above-said a plurality of outboard middle sipes 20 include at least one outboard middle sipe whose axially inner end is connected with the outboard crown main groove 4.

A pneumatic tire provided with, in a tread surface, at least two main circumferential grooves, and a first land portion defined by the two main grooves, wherein in the first land portion, the followings are disposed: a first inclined groove; inclining relative to a tire width direction, and having one end portion opening in the main groove on one side adjacent to the first land portion and the other end portion terminating within the first land portion, and a first notched portion; having one end in a tire width direction as a tip positioned at an endmost, in a tire width direction, of the other end portion of the first inclined groove and the other end in a tire width direction opening in the main groove on the other side adjacent to the first land portion.

A tire has a tread comprising a rubber composition based on at least: an elastomer matrix; a reinforcing filler; a plasticizing agent; and particles; wherein the tread comprises: a tread surface; a sequence of basic pattern(s), wherein each basic pattern has a width (Wm) over at least 80% of the width (W) of the tread, each basic pattern has a pitch (P), and each basic pattern comprises a plurality of raised elements, one or more of which are provided with sipes opening onto the tread surface, wherein each sipe has a width of less than 1 mm and a depth of at least 3 mm; wherein the tread has a sipe density (SD) defined as (I), the SD being less than 60 m/mm.sup.2; where i is the number of sipe(s) in the pattern, l.sub.i is the length of the i sipe on the tread surface.

[00001]$\begin{array}{cc}\mathrm{SD}=\frac{\underset{i}{.Math.}.Math.\mathrm{li}}{P\mathrm{Wm}}& \left(I\right)\end{array}$

Crown of a tire for a heavy vehicle that is desensitized to attacks. The tire (1) comprises tread (2) having a median degree of surface siping TL.sub.C, expressed in m/m.sup.2, equal to the ratio between the cumulative length L.sub.DC of the cuts (21), present in a median portion of tread of axial width W.sub.C, and the median area A.sub.C of the radially outer surface (23) of the tread (2), and protective reinforcement (4) comprising at least two protective layers (41, 42) that are formed of elastic metallic reinforcers and have a maximum breaking strength R.sub.max, expressed in daN/m, such that the median degree of surface siping TL.sub.C of tread (2) is at least equal to 5 m/m.sup.2 and a coupling ratio C.sub.C, equal to the ratio between the maximum breaking strength R.sub.max and the median degree of surface siping TL.sub.C, is at least equal to 18 000 daN.

A pneumatic tire includes at least four circumferential main grooves extending in the tire circumferential direction; and at least five rows of land portions including a center land portion, a pair of second land portions, and a pair of shoulder land portions, which are defined by the circumferential main grooves. Additionally, at least one row of the second land portions is provided with a plurality of lug grooves penetrating through the second land portion in the tire width direction, and a plurality of blocks defined by the plurality of lug grooves. Moreover, the plurality of blocks include one of the circumferential narrow grooves, respectively, which penetrates through the blocks in the tire circumferential direction.