- Tyre for a heavy vehicle of the civil engineering type, comprising: - a tread, a crown reinforcement radially on the inside of the tread, and a carcass reinforcement radially on the inside of the crown reinforcement, - the crown reinforcement comprising, radially from the outside towards the inside, - a protective reinforcement comprising a first protective layer and a second protective layer, radially on the outside of and adjacent to the first protective layer, the first and second protective layers (51, 52) comprising elastic metal reinforcers characterized by a structural elongation As at least equal to 1%, a total elongation at break At at least equal to 4% and a tensile elastic modulus at most equal to 150 GPa, which are parallel to one another within each layer and crossed from one layer to the next, forming respective angles A 1 and A 2 with the circumferential direction (YY'), - a working reinforcement comprising a first working layer and a second working layer, radially on the outside of and adjacent to the first working layer, the first and second working layers (61, 62) comprising inelastic metal reinforcers characterized by a relative elongation, under a tensile force equal to 10% of the breaking force F m, at most equal to 0.2% and a tensile elastic modulus of between 150 GPa and 200 GPa, which are parallel to one another within each layer and crossed from one layer to the next, forming respective angles B 1 and B 2 with the circumferential direction (YY'), where the angle B 1, formed with the circumferential direction (YY') by the metal reinforcers of the first working layer, is non-zero and at most equal to 35° and where the angle B 2, formed with the circumferential direction (YY') by the metal reinforcers of the second working layer is at least equal to 70° and strictly less than 90°, characterized in that the crown reinforcement comprises, radially on the inside of the working reinforcement, an additional reinforcement comprising a first additional layer and a second additional layer, radially on the outside of and adjacent to the first additional layer, the first and second additional layers (71, 72) comprising inelastic metal reinforcers which are parallel to one another within each layer and crossed from one layer to the next, forming respective angles C 1 and C 2 at most equal to 15° with the circumferential direction (YY'). - a tread, a crown reinforcement radially on the inside of the tread, and a carcass reinforcement radially on the inside of the crown reinforcement, - the crown reinforcement comprising, radially from the outside towards the inside, - a protective reinforcement comprising a first protective layer and a second protective layer, radially on the outside of and adjacent to the first protective layer, the first and second protective layers (51, 52) comprising elastic metal reinforcers characterized by a structural elongation As at least equal to 1%, a total elongation at break At at least equal to 4% and a tensile elastic modulus at most equal to 150 GPa, which are parallel to one another within each layer and crossed from one layer to the next, forming respective angles A 1 and A 2 with the circumferential direction (YY'), - a working reinforcement comprising a first working layer and a second working layer, radially on the outside of and adjacent to the first working layer, the first and second working layers (61, 62) comprising inelastic metal reinforcers characterized by a relative elongation, under a tensile force equal to 10% of the breaking force F m, at most equal to 0.2% and a tensile elastic modulus of between 150 GPa and 200 GPa, which are parallel to one another within each layer and crossed from one layer to the next, forming respective angles B 1 and B 2 with the circumferential direction (YY'), where the angle B 1, formed with the circumferential direction (YY') by the metal reinforcers of the first working layer, is non-zero and at most equal to 35° and where the angle B 2, formed with the circumferential direction (YY') by the metal reinforcers of the second working layer is at least equal to 70° and strictly less than 90°, characterized in that the crown reinforcement comprises, radially on the inside of the working reinforcement, an additional reinforcement comprising a first additional layer and a second additional layer, radially on the outside of and adjacent to the first additional layer, the first and second additional layers (71, 72) comprising inelastic metal reinforcers which are parallel to one another within each layer and crossed from one layer to the next, forming respective angles C 1 and C 2 at most equal to 15° with the circumferential direction (YY').