Tire for heavy goods vehicle having a tread comprising a plurality of circumferential grooves delimiting intermediate ribs and two edge ribs each circumferential groove comprising a plurality of protuberances formed as a protrusion on at least one lateral wall delimiting this groove, wherein: facing each protuberance, a half-closed notch has an axial length La at most equal to 60% of the minimum width Ln of this rib, and a width Le at most equal to the width Lr of the groove oriented so as to make an average angle B at least equal to 10 degrees with the main direction of the protuberance, each protuberance closes the section of the groove in which it is formed over at least 35% and at most 75% of the surface of the said section, a functional clearance (J1, J2) is arranged between the protuberance and the walls delimiting the half-closed notch.