A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95≤MC≤180, where MC=(J×MI+L×ME)/(J+L); MI=200×cos.sup.4(α)×[Q×(D1/2).sup.2×cos.sup.4(β)+P×(D2/2).sup.2×cos.sup.4(δ)+N×(D3/2).sup.2×cos.sup.4(γ)]/[Q×(D1/2).sup.2+P×(D2/2).sup.2+N×(D3/2).sup.2]; and ME=200×cos.sup.4(α′)×[Q′×(D1′/2).sup.2×cos.sup.4(ββ)+P′×(D2′/2).sup.2×cos.sup.4(δ′)+N′×(D3′/2).sup.2×cos.sup.4(γ′)]/[Q′×(D1′/2).sup.2+P′×(D2/2).sup.2+N′×(D3′/2).sup.2], where D1, D1′, D2, D2′, D3 and D3′ are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), δ and δ′ are the helix angle of each intermediate thread (F2, F2′) and γ and γ′ are the helix angle of each external thread (F3, F3′).

A tire includes a carcass ply, a tread disposed radially outward of a crown region of the carcass ply, and a belt structure having an overall axial width substantially equal to a tread width interposed between the tread and the crown region in circumferential surrounding relation to the carcass ply. The belt structure includes a first belt layer and a second belt layer radially adjacent the first belt layer. The first belt layer includes a first reinforced composite with first reinforcement cords embedded in a first rubber matrix. The first reinforcement cords have a construction of 1100/4 dtex with a twist between 150 TPM and 250 TPM and a dipping tension between 100 mN/tex and 200 mN/tex.

The invention relates to a radial pneumatic tire (1) for a heavy-duty civil engineering vehicle and aims to reduce the risk of tread separation of the pneumatic tire, during driving on sharp rocks, while ensuring good resistance to cracking of the crown reinforcement. The pneumatic tire (1) comprises a protective reinforcement (5) comprising two protective layers (51, 52), the radially innermost protective layer (51) comprising elastic metal reinforcements with a diameter D1 which are axially distributed according to an axial pitch P1, and the radially outermost protective layer (52) comprising elastic metal reinforcements with a diameter D2 which are axially distributed according to an axial pitch P2. According to the invention, the following relations are satisfied:

D1>D2

P1>P2

P1>=1.2*D1 et P2>=1.2*D2

2.5<=(DI*P1)/(D2*P2)<=5

The invention relates to a tyre comprising a working reinforcement comprising a single working ply, a carcass reinforcement and a hoop reinforcement. The hooping reinforcing textile filamentary element or elements (480), the working reinforcing filamentary elements (460) and the carcass reinforcing filamentary elements (440) are arranged so as to form a triangular mesh in projection on the circumferential equatorial plane (E). The or each hooping reinforcing textile filamentary element (480) is formed by a cord (30) with a triple twist (T1, T2, T3), comprising an assembly (25) consisting of N>1 strands (20a, 20b, 20c) twisted together with a twist T3 in a direction D2, each strand consisting of M>1 pre-strands, which are themselves twisted together with a twist T2 (T2a, T2b, T2c) in a direction D1 opposite to D2, each pre-strand itself consisting in a yarn that has been previously twisted about itself with a twist T1 in the direction D1, wherein at least half of the N times M yarns consist of elementary monofilaments of aromatic polyamide or aromatic copolyamide.

The present invention concerns a radial tire (1) for a heavy civil-engineering vehicle, and aims to increase the resistance to repeated impact of its crown reinforcement (3), when driving over stones, while maintaining good resistance to attacks. The tire (1) comprises a protective reinforcement (5) comprising at least one protective layer (51, 52) comprising elastic metal reinforcers, and a working reinforcement (6) comprising two working layers (61, 62) comprising non-extensible metal reinforcers, the elastic metal reinforcers of the radially innermost protective layer (51) have a elastic modulus in extension of at least 100 GPa and a diameter D of at least 3 mm, and are distributed axially at an axial pitch P at least 1.2 times the diameter D.

A pneumatic tire having a carcass and a belt reinforcing structure wherein the belt reinforcing structure is a composite belt structure having at least one radially inner spiral layer and at least one zigzag belt reinforcing structure located radially outward of said spiral layer. The zigzag belt width is preferably wider than the spiral layer. The spiral layer and at least one of the zigzag belts reinforcing structures is preferably formed of a merged cord of aramid and nylon.

A pneumatic tire having a carcass and a belt reinforcing structure wherein the belt reinforcing structure is a composite belt structure having at least one radially inner spiral layer and at least one zigzag belt reinforcing structure located radially outward of said spiral layer. The zigzag belt width is preferably wider than the spiral layer. The spiral layer and at least one of the zigzag belts reinforcing structures is preferably formed of a merged cord of aramid and nylon.

A tire includes a tread and a crown reinforcement arranged radially internal to the tread. The crown reinforcement includes a protective reinforcement and a working reinforcement. The protective reinforcement includes a protective ply that exhibits a force at break greater than or equal to 1300 daN.Math.cm.sup.1. The protective ply includes protective reinforcing elements, each of which exhibits a force at break greater than or equal to 3000 N. The working reinforcement is arranged radially internal to the protective reinforcement and includes a working ply. The working ply includes working reinforcing elements, each of which includes a working cord formed of at least a strand that includes an external layer of unsaturated threads.

The invention relates to a rubberized reinforcing ply (1) for articles consisting of an elastomeric material, preferably for vehicle tires, wherein the reinforcing ply (1) has a multiplicity of textile strengthening members (2) which are arranged parallel to and spaced apart from one another, wherein each textile strengthening member (2) is composed of at least one twisted multifilament yarn, and wherein the textile strengthening member (2) is not composed of the material rayon. The reinforcing ply (1) satisfies the following condition: (D.sup.2/E.sub.0) in mm corresponds to a value in a range from 0.22 mm to 0.38 mm, and the reinforcing ply (1) has a strength of >10 kN/dm, where D is the diameter of the textile strengthening member (2) in mm and lies in a range from 0.38 mm to 0.52 mm, and where E.sub.0=100/epdm.

A two-layer multi-strand cord (60) has a modulus EC such that 50 GPaEC160 GPa. The cord comprises: (a) an internal layer (CI) of the cord made up of J>1 internal strands (TI) wound in a helix having a modulus EI, each internal strand (TI) comprising: an internal layer (C1) made up of Q1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1), and (b) an external layer (CE) of the cord made up of L>1 external strands (TE) wound around the internal layer (CI) of the cord, each external strand (TE) comprising: an internal layer (C1) made up of Q1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1).