Civil engineering tire tread

A tread for a civil engineering tire, this tread made of rubber being provided with circumferential grooves and transverse grooves,

• wherein these circumferential and transverse grooves have a depth and a width and delimit a plurality of raised elements forming a tread surface and comprising two edge rows of the tread,
• wherein each edge row is provided with a plurality of blocks axially bounding the tread over a maximum axial width corresponding to the contact width in conditions of use,
• wherein the blocks of each edge row of the tread, in pairs, delimit a groove of transverse overall orientation opening both onto a circumferential groove and to an outside of the tread,
• wherein each block of the edge rows comprises:
• a contact face adapted to come into contact with a ground surface,
• two lateral faces—comprising an external lateral face and an internal lateral face,
• a front face and a rear face, wherein these front and rear faces are spaced apart in the circumferential direction, and wherein the front face and the rear face intersect the contact face along a front edge corner and a rear edge corner respectively,
• wherein the blocks of each edge row are formed in such a way that their external lateral faces all lie the same distance from an equatorial plane that divides the tread into two tread halves of equal width,
• wherein the tread has a maximum axial width between axial limits of the tread corresponding to the maximum axial distance between the external lateral faces of the blocks of the edge rows,
• wherein the width of the transverse grooves between the blocks of the edge rows, this width being measured on the tread surface, increases progressively at least from a non-zero distance measured from a plane parallel to the equatorial plane and passing through the axially outermost points of the external lateral faces of the blocks of the edge rows of the tread,
• wherein, with each block having a maximum circumferential length Lc, the maximum increase in width of the transverse groove is at least equal to 20% of this maximum circumferential length Lc and at most equal to 50% of this maximum circumferential length Lc, and
• wherein every other block in each edge row defines a parallelepiped shape.