Pneumatic tire

A pneumatic tire formed with a plurality of rib-shaped land portions separated by circumferential grooves extending in a tread circumferential direction, comprising:

• elongate projection portions projecting toward each other from the rib-shaped land portions adjacent to each other with one of the circumferential grooves therebetween, the elongate projection portions being formed in an annular shape extending in the tread circumferential direction;
• the elongate projection portions confronting each other are disposed with a spacing therebetween such that mutually confronting tip surfaces of the elongate projection portions make contact with each other through elastic deformation of the rib-shaped land portions at a time of grounding of the tire;
• the circumferential groove has formed therein with an inside groove space on a radially inner side of the confronting elongate projection portions, and with an outside groove space on a radially outer side of the confronting elongate projection portions;
• the confronting elongate projection portions have confronting tip surfaces thereof formed with a plurality of communication recesses providing communication between the outside groove space and the inside groove space, the communication recesses being formed at intervals in the tread circumferential direction;
• the elongate projection portions projecting from the rib-shaped land portions are formed to extend to the tip surfaces, respectively, in a form of a conical surface extending radially inward from tread surfaces on the rib-shaped land portions;
• and
• the elongate projection portions in the circumferential grooves on outermost areas in a tread width direction have a smaller inclination angle of the conical surface than an inclination angle of the conical surface of the elongate projection portions in the circumferential grooves in a central area in the tread width direction;
• the inclination angles being inclined with respect to the tread surfaces.