A heavy duty pneumatic tire includes a tread portion provided with at least one circumferentially extending main groove, at least one circumferentially extending sub groove, and a plurality of lateral grooves to form repeated pitch elements each of which consists of one lateral groove and a block element. The sub groove includes a shallow bottom part with a depth smaller than that of the main groove. The shallow bottom part of the sub groove is provided with a groove bottom sipe. The lateral grooves include a shallow bottom part with a depth smaller than that of the main groove. The shallow bottom part of the lateral groove is provided with a groove bottom sipe. The lateral grooves have groove widths W2 in a range of from 5% to 15% in relation to a circumferential length L1 of the pitch element.

A pneumatic tire includes: a first and second main grooves extending in a tire circumferential direction; first and second inclined grooves extending obliquely toward the same side with respect to the tire circumferential direction and connected to the first and second main grooves; and a block defined by the first and second main grooves and the first and second inclined grooves. The block includes a sub groove having a first portion and a second portion, the first portion being open to an intermediate portion of the first inclined groove and extending in the tire circumferential direction, the second portion being inclined to a side opposite to the first inclined groove, extending from a terminal end of the first portion in a direction away from the first inclined groove, and being open to the first main groove.

In a pneumatic tire, a plurality of lands include a first land, the first land comprises a plurality of circumferential grooves that extend in a tire circumferential direction and that are arrayed in a tire axial direction, the plurality of circumferential grooves are respectively arranged at portions in the tire circumferential direction of the first land, the plurality of circumferential grooves include a first circumferential groove which is arranged in inwardmost fashion in the tire axial direction, and a second circumferential groove which is arranged in outwardmost fashion in the tire axial direction, and as viewed in a tire meridional section, an inner space area of the first circumferential groove is greater than an inner space area of the second circumferential groove.

A pneumatic tire includes: a first longitudinal groove and a second longitudinal groove extending in a tire circumferential direction; a first lateral groove extending obliquely with respect to a tire width direction and connected to the first longitudinal groove and the second longitudinal groove; a second lateral groove extending obliquely toward a side opposite to the first lateral groove with respect to a tire width direction and connected to the first longitudinal groove and the second longitudinal groove; and a trapezoidal block defined by the first longitudinal groove, the second longitudinal groove, the first lateral groove, and the second lateral groove. The block includes a first sipe and a second sipe extending obliquely toward opposite sides in the tire width direction.

A pneumatic tire includes a tread having a center main groove and a pair of shoulder main grooves. A pair of middle land sections in the tread is positioned between the shoulder and center grooves. Each of the shoulder and center grooves has a groove width set in range of 7 to 9% of width of the tread footprint. An outer middle land portion is divided into first and second middle land portions by a middle narrow groove. The first land portion forms rib. The second land portion has outer middle lateral grooves connected to the center groove and the narrow groove. Each lateral groove includes first portion, second portion having the opposite inclination to the first portion and connection portion between the first and second portions. The connection portion is positioned on the center groove side from the center of the outer land portion in the axial direction.

A heavy-duty pneumatic tire includes a tread pattern including center lug grooves, shoulder lug grooves, a pair of circumferential primary grooves formed in wave-like shapes by alternately connecting ends of the center lug grooves and ends of the shoulder lug grooves and having a smaller width than the width of the shoulder lug grooves, center blocks defined by the center lug groove and the circumferential primary grooves, and a circumferential secondary groove extending in the tire circumferential direction so as to divide regions of the center blocks. The belt portion includes two or greater pairs of belts. The ratio of the width W8 of a belt having a smaller width in each of the belt pairs to the width W7 of a belt having a greater width is 0.75 or greater and 0.90 or less.

The present technology provides a heavy duty pneumatic tire with a tread portion having a tread pattern including: a pair of circumferential primary grooves defined in a wave-like shape and extending in the tire circumferential direction; center lug grooves; center blocks; and circumferential secondary grooves extending in regions of the center blocks and open to the center lug grooves. The center lug grooves have two groove turning portions turned in a bend shape or a curved shape. The circumferential secondary grooves extend in an inclined manner relative to the tire circumferential direction. An inclination angle (θ.sub.4) of the circumferential secondary grooves relative to the tire circumferential direction is different from an inclination angle (θ.sub.1) of portions of the circumferential primary grooves relative to the tire circumferential direction, the portions extending toward the same side as a side in the tire width direction, toward which the circumferential secondary grooves are inclined.

A pneumatic tire with improved heat build-up resistance in a land portion in a tread center region. The pneumatic tire is provided with a tread pattern that includes a plurality of center lug grooves (14) disposed at intervals in a tire circumferential direction that cross a tire equator line; a plurality of shoulder lug grooves (12A, 12B) disposed in intervals between the plurality of center lug grooves in the tire circumferential direction extending outward in the tire width direction, an inner end in the tire width direction being disposed outward of an end of the center lug groove in the tire width direction; a pair of circumferential primary grooves (11A, 11B) extending around an entire circumference of the pneumatic tire in a wave-like shape with the ends of the center lug grooves and the inner ends of the plurality of shoulder lug grooves in the tire width direction alternately connecting to the pair of circumferential primary grooves (11A, 11B); and a circumferential secondary groove (10) disposed on the tire equator line around the entire circumference of the pneumatic tire that intersects the center lug grooves.

A straight line that joins an intersection portion between the center lug groove and the circumferential secondary groove and the end of the center lug groove has an inclination angle with respect to the tire circumferential direction ranging from 55° to 75°.

The ground contact end is an end of a tread surface in the tire width direction in a state where the tire at an internal pressure of 230 kPa is under a load of 70% of the maximum load according to the load index. The predetermined region T is a region in a portion outside the ground contact end in the tire width direction and is defined between the ground contact end and a location spaced apart from the ground contact end by a distance corresponding to 8% or more and 15% or less of a width from the ground contact end to the other ground contact end in the tire width direction. The predetermined direction forms an angle of 0 degrees or more and 35 degrees or less with respect to a circumferential direction of the tire.

Provided is a pneumatic tire including a plurality of main grooves extending in the tire circumferential direction in a tread portion and including a sipe extending in a tire width direction on a rib defined by a main groove, the sipe includes a leading side edge and a trailing side edge, a chamfered portion shorter than a sipe length of the sipe is formed in each of the leading side edge and the trailing side edge, a non-chamfered region including no other chamfered portion is present in a part facing each chamfered portion of the sipe, and the rib includes an intersecting groove intersecting with at least one out of the sipe and the chamfered portion.