[0001] The present disclosure relates to structural cables used in the construction industry. It is applicable, in particular, to stay cables used for supporting, stiffening or stabilizing structures.

[0002] Stay cables are widely used to support suspended structures such as bridge decks or roofs. They can also be used to stabilize erected structures such as towers or masts.

[0003] A typical structure of a stay cable includes a bundle of tendons, for example wires or strands, housed in a collective plastic sheath. The sheath protects the metallic tendons of the bundle and provides a smooth appearance of the stay cable.

[0004] In certain cases, the sheath is in the form of an integral tube which extends between the two anchoring points of the stay cable. The tendons are threaded, usually one by one or small groups by small groups, into the sheath before anchoring them at both ends. An integral tube is continuous, which provide multiple advantages in terms of mechanical tensile, compression capacity, air or water tightness, or aerodynamic profile.

[0005] In other cases, the sheath is made of segments following each other along the cable. Each segment can be made of several sectors assembled around the bundle of tendons (see, e.g., US patent 5,479,671).

[0006] It is sometimes necessary or desirable to replace the sheath of a stay cable, for example because the existing sheath is damaged or for aesthetic reasons. The sheath can be replaced by disassembling the cable. However, this is tedious and lengthy. It also involves risks due to the loss of the contribution of the stay cable to the stability of the structure, which may require the deployment of a temporary consolidation structure.

[0007] An object of the present disclosure is to address the above need in a simpler way.

[0008] The present disclosure proposes a method of arranging a sheath on a stay cable having a bundle of tendons tensioned between anchoring points. The method comprises: assembling first and second sheath elements around the bundle of tendons such that longitudinal edges of the first and second sheath elements face each other; and welding the first and second sheath elements together along the longitudinal edges thereof to form a first sheath segment surrounding the bundle of tendons.

[0009] With such a method, the sheath of a stay cable can be replaced (or an original sheath can be installed) while the tendons remain (are already) anchored at their ends. [0010] Embodiments of the method further comprise: moving the first sheath segment along the bundle of tendons to clear a working space for forming a second sheath segment around the bundle of tendons; assembling third and fourth sheath elements around the bundle of tendons in the working space such that longitudinal edges of the third and fourth sheath elements face each other; and welding the third and fourth sheath elements together along the longitudinal edges thereof to form the second sheath segment.

[0011] In such an embodiment, the first and second sheath segments may be welded together along their transversal edges which face each other.

[0012] Embodiments of the method further comprise, prior to assembling the first and second sheath elements: providing a duct portion having a desired cross-section; cutting the duct portion longitudinally to obtain the first and second sheath elements; and maintaining shapes of the first and second sheath elements in accordance with the desired cross-section to ensure that the first sheath segment will have the desired cross-section after welding the first and second sheath elements together.

[0013] Maintaining the shapes of the first and second sheath elements may be performed using a clamping system comprising at least one first brace in contact with an inner face of the first sheath element and at least one second brace in contact with an inner face of the second sheath element. The first and second braces may be maintained in contact with the inner faces of the first and second sheath elements when the first and second sheath elements are welded together along their longitudinal edges.

[0014] In some embodiments, the clamping system comprises, optionally in combination with the above mentioned first and second braces, at least one third brace in contact with an outer face of the first sheath element and at least one fourth brace in contact with an outer face of the second sheath element. The third and fourth braces may be maintained in contact with the outer faces of the first and second sheath elements when the first and second sheath elements are welded together along their longitudinal edges.

[0015] After welding the first and second sheath elements together along their longitudinal edges, the following may also be performed: separating the first, second, third and fourth braces from the first sheath segment; moving the first sheath segment along the bundle of tendons toward a previously formed sheath segment; bringing the first and second braces again in contact with the sheath segment to provide alignment with the previously formed sheath segment; and welding the first sheath segment to the previously formed sheath segment along transversal edges thereof.

[0016] The present document further discloses a device for arranging a sheath on a stay cable having a bundle of tendons tensioned between anchoring points. The device comprises: a support part for positioning first and second sheath elements around the bundle of tendons such that longitudinal edges of the first and second sheath elements face each other; and a longitudinal welding tool for welding the first and second sheath elements along the longitudinal edges thereof to form a first sheath segment surrounding the bundle of tendons.

[0017] The support part may include a clamping system comprising at least one first brace adapted to be in contact with an inner face of the first sheath element and at least one second brace adapted to be in contact with an inner face of the second sheath element. It may comprise, optionally in combination with the first and second braces, at least one third brace adapted to be in contact with an outer face of the first sheath element and at least one fourth brace adapted to be in contact with an outer face of the second sheath element. Additionally, the clamping system may comprise clips disposed at axial ends of the first, second, third and fourth braces for maintaining the first sheath element between the first and third braces and the second sheath element between the second and fourth braces. The clips may be associated with a device for adjusting a thickness of a gap formed within the clamping system between outer contours of the first and second braces and inner surfaces of the third and fourth braces.

[0018] A gap, in a typical range of 5 mm to 40 mm, may be formed between the first and second braces when the first and second braces are in contact with the inner faces of the first and second sheath elements.

[0019] In embodiments of the device, the support part further comprises first and second collars to be disposed around the bundle of tendons, and support bars extending longitudinally between the first and the second collars.

[0020] The support bars may be arranged as a first pair of support bars on one side of the bundle of tendons and a second pair of support bars on an opposite side of the bundle of tendons, each pair of support bars having a first support leg for supporting the first brace and a second support leg for supporting the second brace. The support part may further comprise actuators controllable to change a distance between the first and second support bars of each pair of support bars. Such actuators may be mounted on at least one of the first and second collars.

[0021] In embodiments of the device, the longitudinal welding tool comprises a pair of heating plates introduced in gaps formed on both sides of the stay cable between the longitudinal edges of the sheath elements positioned around the bundle of tendons.

[0022] A transversal welding tool may also be provided for welding the first sheath segment to a previously formed sheath segment along transversal edges thereof around the bundle of tendons. The transversal welding tool may comprise a pair of heating plates inserted in a space formed between the transversal edges of the first sheath segment and the previously formed sheath segment.

[0023] Other features and advantages of the method and the device disclosed herein will become apparent from the following description of non-limiting embodiments, with reference to the appended drawings, in which:

Figure 1 is a schematic view of stay cable;

Figure 2A is a side view of a duct portion in a preparation station of a device as disclosed herein;

Figure 2B is a cross-sectional view corresponding to figure 2A;

Figures 3A and 3B are views corresponding to Figs. 2A-B after the duct portion is cut at the preparation station;

Figure 4 is a side view of elements of a support part that belong to an assembly station, arranged around a bundle of tendons;

Figure 5 is a side view of the support part with sheath elements;

Figure 6 is a cross-sectional view corresponding to figure 5, along plane VI shown in figure 5;

Figures 7, 8 and 9 are cross-sectional views similar to figure 6, illustrating different steps of a method according to the present disclosure;

Figure 10 is a side view of the support part, with sheath segments arranged around the bundle of tendons; and

Figure 11 is a side view similar to Fig. 10, at a later stage of a method according to the present disclosure.

[0024] Figure 1 shows a stay cable 10 configured to take up efforts applied to a structure 12 to which it is anchored. To that end, it extends between two parts 14, 16 of a construction work. The first part 14 is for instance at a higher position than the second part 16. For example, the first part 14 belongs to the structure 12, such as a tower, while the second part 16 belongs to a foundation to stabilize the structure. Alternatively, the first part 14 may belong to a pylon, while the second part 16 belongs to some structure suspended from the pylon, e.g., a bridge deck.

[0025] The construction work typically includes a number of stay cables 10, only one of them being shown in figure 1.

[0026] The stay cable 10 comprises a load-bearing part 18 which comprises a bundle of tendons 20 disposed parallel to each other (see figures 6-9). The bundled tendons may be strands of a similar type as used to pre-stress concrete structures. They are for instance made of steel. Each strand may optionally be protected by a substance such as grease or wax and/or individually contained in a respective plastic sheath. The stay cable 10 may have a length of up to several hundred meters. The bundle 20 may include a few tens of tendons.

[0027] The tendons of the bundle 20 are anchored at both ends of the bundle at two anchoring points 22, 24. In the example shown, a first anchoring device is mounted on the first part 14 of the construction work at an upper anchoring point 22, while a second anchoring device is mounted on the second part 16 of the construction work at a lower anchoring point 24. Between the two anchoring points 22, 24, the bundle of tendons follows a catenary curve due to the weight of the cable and the tensile force maintained by the anchoring devices.

[0028] Referring to figure 1, in addition to the load-bearing part 18, the cable 10 includes a sheath 26 within which the bundle 20 is received. The sheath 26 forms a protective structure for the bundle.

[0029] In the example illustrated in figure 1, the first end of the sheath 26 bears on a guide tube through which the bundle of tendons passes near the lower anchoring point 24, while the second end of the sheath 26 penetrates into another tube disposed on the first part 14 of the construction work, through which the upper end of the bundle of tendons passes to reach the upper anchoring point 22.

[0030] In the non-limiting example shown in the figures, the sheath 26 has a circular cross-section. It is typically made of high-density polyethylene (HDPE). The bundle of tendons may be compacted as illustrated in figures 6-9.

[0031] In circumstances where the sheath 26 needs to be replaced, it is proposed to do so by keeping the tendons under tension, i.e., without separating their anchored ends from the construction work at the anchoring points 22, 24. First, the existing sheath 26 is removed, for example by cutting it and taking the pieces off the cable 10. Then, a method is used for arranging a new sheath on the stay cable while the tendons remain tensioned. [0032] The method may be applied starting from a duct having a cross-section that matches the desired cross-section of the new sheath to be installed on the stay cable 10, e.g., a circular crosssection with a diameter in a range of 10 to 80 cm. The duct is cut into duct portions 21 (figures 2A-B) having a hollow cylindrical shape and a length L in a typical range of 1 to 12 m, for example 2 to 6 m.

[0033] The duct from which the duct portions 21 are cut may have a pattern of protrusions or dimples (not shown) configured to increase the resistance and stability to the combined effects of rain and wind. Such protrusions may conventionally take the form of helical ribs formed on the outer surface 29 of the duct.

[0034] The duct portion 21 is cut longitudinally to obtain a pair of semi-cylindrical sheath elements 33, 34 that extend along the longitudinal axis X shown in figures 2A-B and 3A-B. For example, the first and second sheath elements 33, 34 may be symmetrical with respect to each other, according to a plane of symmetry passing through the longitudinal axis X (plane X-Y in figures 3A-B). Each sheath element 33, 34 has an outer face 37 corresponding to the outer surface 29 of the duct portion 21, an inner face 38 corresponding to the inner surface 28 of the duct portion 21, two longitudinal edges 35 and two transversal edges 36. The longitudinal edges 35 are linear and extend along the lines where the duct portion 21 is cut to obtain the sheath elements 33, 34. The transversal edges 36 correspond to the axial ends of the duct portion 21 and extend in the Y-Z plane shown in figures 3A-B.

[0035] The division of the duct segment into sheath elements, as well as any additional preparation of the sheath elements, is performed with a preparation station shown in figures 2A-B, which may be installed on the bridge deck when the construction work is a cable-stayed bridge.

[0036] An assembly station installed on the stay cable 10 is then used to form a sheath segment around the bundle of tendons 20 by joining the first and second sheath elements 33, 34 together along their longitudinal edges 35. Such sheath segment will have the desired cross-section which was that of the duct from which the sheath elements 33, 34 were cut. Successive sheath segments thus formed may then be butt-welded at their transversal edges 36 and pushed along the bundle of tendons 20.

[0037] The device for arranging a new sheath on the stay cable 10 provides a solution to arrange at least a portion of a sheath on the stay cable of a construction work already built. The device comprises the above-mentioned preparation and assembly stations. It includes a support part 50. It also includes, at the assembly station, a longitudinal welding tool 70 and a transversal welding tool 80.

[0038] The support part 50 is used to position and assemble the sheath elements 33, 34 around the bundle of tendons 20. The support part 50 comprises a clamping system 51. It also comprises collars 52a-c and support bars 54 which belong to the assembly station.

[0039] The clamping system 51 is used to maintain the desired cross-section of the assembly of the sheath elements 33, 34 when the sheath elements are handled and eventually welded together. When longitudinally cutting the duct portion 21, some relaxation of the plastic material may cause a change of the cross-sectional shape of the first and second sheath elements 33, 34. In particular, the distance between the longitudinal edges 35 may become smaller or larger than the diameter of the desired circular cross-section of the sheath, depending on the stress distribution within the duct. The clamping system 51 holds the sheath elements 33, 34 to prevent such undesirable deformation.

[0040] In the case of the preparation station illustrated in figures 2A-B and 3A-B, the clamping system 51 comprises first and second braces 55, 56 adapted to be in contact with the inner surface 28 of the duct portion 21. The braces 55, 56 have a semi-cylindrical outer contour that matches the inner diameter of the sheath duct portion 21. As shown in figures 2A-B, there is a gap 58 between the first and second braces 55-56. The gap 58 extends along the diameter plan X-Y indicated by a dotted line in figures 2A-B. At the time of dividing the duct portion into the sheath elements 33, 34, a cutting tool penetrates the gap 58. The gap 58 will also be used for insertion of the longitudinal welding tool 70 at the time of welding the sheath elements 33, 34 together, as described in greater detail below. The gap 58 may be in a range of 5 mm to 40 mm, for example 20 mm.

[0041] To better hold the sheath elements 33, 34 when the duct portion 21 is cut and thereafter, the clamping system 51 may also comprise third and fourth braces 59, 60 adapted to be in contact with the outer surface 29 of the duct portion 21. The braces 59, 60 have a semi-cylindrical inner surface that matches the outer diameter of the sheath duct portion 21. As shown in figures 2A-B, the gap 58 along the diameter plan X-Y indicated by a dotted line also extends between the third and fourth braces 59, 60, to leave room for penetration of the cutting tool.

[0042] Once the duct portion 21 is cut, the braces 55, 56 are in contact with the inner faces 38 of the sheath elements 33, 34, respectively, while the braces 59, 60 are in contact with the outer face 37 of the sheath elements 33, 34, respectively. Such contacts will be maintained when the sheath elements 33, 34 are welded together along their longitudinal edges 35.

[0043] According to an example, the first and second braces 55, 56 may be convex plates extending along the longitudinal axis X. Those plates may extend over substantially the full length of the sheath elements 33, 34. According to another example, the first braces 55 in contact with the inner faces 38 of the first sheath elements 33 are plural and spaced along the longitudinal direction X, as well as the second braces 56 in contact with the inner faces 38 of the second sheath elements 34. In such a configuration, the braces 55, 56 are connected to each other, for example by longitudinal coupling rods.

[0044] The first and second braces 55, 56 are adapted to cooperate with the support bars 54 described further below. [0045] According to an example, the third and fourth braces 59, 60 may be concave plates extending according to the longitudinal axis X. Those plates may extend over substantially the full length of the sheath elements 33, 34. According to another example, the third braces 59 in contact with the outer faces 37 of the first sheath elements 33 are plural and spaced along the longitudinal direction X, as well as the fourth braces 60 in contact with the outer faces 37 of the second sheath elements 34. In such a configuration, the braces 59, 60 are connected to each other, for example by longitudinal coupling rods.

[0046] As illustrated in figures 2A-B and 3A-B, the clamping system 51 may also comprise longitudinal guides 63 on both sides of the duct portion 21 where a cut is to be made. Each longitudinal guide is in the form of a pair of rails 63 attached to the third and fourth braces 59, 60, respectively, next to their longitudinal edges 57, in order to guide the cutting tool when dividing the duct portion 21 into the sheath elements 33, 34.

[0047] The collars 52a-c shown in figure 4 are arranged around the bundle of tendons 20. There are three collars 52a-c shown in the example of assembly station. In certain cases, two collars only may be sufficient. More than three collars may also be arranged around the bundle of tendons 20 without departing from the scope of the disclosure.

[0048] Each collar 52a-c is connected to the bundle of tendons 20. It may have a hinge and a locking system to be easily placed on or removed from the bundle of tendons 20. The collar may be completed with cushions 61, illustrated in figures 6-9, to firmly bear on the tendons 20. The cushions 61 are inserted between the inner face of the collar and the periphery of the bundle of tendons 20. It may be for example inflatable or made of wood or plastic, or from pieces of metallic strands. The external diameter of the collars 52b-c is smaller than the internal diameter of the sheath segment formed by assembling two sheath elements 33, 34. In that way, the sheath segment may slide upwards along the bundle of tendons 20. The first (lowermost) collar 52a may have an external diameter smaller or larger than the internal diameter of the sheath segment. The first collar 52a may support a jack system 64, hydraulic or pneumatic or electromagnetic, in order to move the sheath segment longitudinally towards the third (uppermost) collar 52c, as described in greater detail below.

[0049] The first and the second collars 52a, 52b are spaced by a distance DI at least equal to the length L of the sheath elements 33, 34. The interval between the first and the second collars 52a, 52b defines a working space 90 for assembling a sheath segment. The second and the third collars 52b, 52c are spaced at a distance D2 smaller than the distance DI. The distance D2 may be in a range of 25% to 75% of the length L of the sheath elements 33, 34.

[0050] The support bars 54 are mounted on the collars 52a-c of the support part 50. In the example shown in figures 6-9, the support bars 54 are arranged as two pairs on both sides of the tendons 20, diametrically opposed from each other. The support bars 54 provide longitudinal alignment of the collars 52a-c. The collars 52a-c have slots which extend between the two support bars 54 of each pair to allow an adjustment of the spacing between those two support bars 54. Actuators 62 shown schematically in figures 6-9 are provided to adjust that spacing, within a stroke in a range of +/- 40 mm for example, preferably +/- 20 mm. The actuator 62 may be hydraulic to be able to provide an easy pressure control for the longitudinal welding step. The actuators 62 may for example be housed in the first collar 52a, and optionally duplicated in the second collar 52b.

[0051] As shown in figures 6-9, protrusions 100 are formed on the inner face of the convex plates forming the first and second braces 55, 56 of the clamping system 51. The protrusions 100 extend longitudinally and include longitudinal grooves 101 adapted to bear on the support bars 54 while allowing a sliding movement along the stay cable.

[0052] Figures 5-6 show two sheath elements 33, 34 brought with the clamping system 51 around the bundle of tendons 20 in the working space 90 of the assembly station. The sheath elements are assembled and positioned by the cooperation of the support bars 54 with the grooves 101.

[0053] The clamping system 51 may further comprise clips (not shown) to be disposed at the axial ends of the braces 55, 56, 59, 60. Those clips are used to maintain the thickness of the annular gap formed within the clamping system 51 by applying a radial force, illustrated by the arrows A in figures 6 and 8, between the first and third braces 55, 59 and between the second and fourth braces 56, 60. An adjustment of the gap thickness may be provided by means of screws cooperating with the clips. Those screws provide a capability of radial displacement in a range of +/- 2 mm, for example, which may be useful to perfectly align the longitudinal edges 35 of the sheath elements 33, 34 before the welding step.

[0054] Once the sheath elements 33, 34 have been cut at the preparation station (figures 2A-B and 3A-B), maintained in the clamping system 51 and assembled at the assembly station (figures 5-6), positional adjustments are performed using the screws associated with the clips and the actuators 62 to check whether the longitudinal edges 35 of the two sheath elements 33, 34 face each other with a proper alignment, as illustrated in figure 7. If not, the screws can be again manipulated to improve the alignment. Optionally, the collars 52a-b may be additionally fitted with lateral actuators (not shown) to provide relative movement of the sheath elements 33, 34 (from left to right or vice-versa in the representation of figures 6-7).

[0055] At that time, the actuators 62 are again used to move the sheath elements 33, 34 away from each other, to obtain, between their longitudinal edges 35, a distance sufficient for introduction of the longitudinal welding tool 70.

[0056] The longitudinal welding tool 70 includes two heating plates that are introduced in the gaps formed on both sides of the stay cable between the sheath elements 33, 34 (figure 8). The heating plates 70 are brought to a temperature T suitable for locally melting the plastic material of the sheath elements at their longitudinal edges 35. After the introduction of the heating plates 70, the actuators 62 are again used to bring the longitudinal edges 35 of the sheath elements 33, 34 into contact with the heating plates and apply a pressure Pl for a time tl at the contacts between the edges 35 and the plates 70. Thereafter, the sheath elements 33, 34 are separated to remove the heating plates 70, and brought again in contact along their molten longitudinal edges 35. The actuators 62 are again used to apply a pressure P2 for a time t2. The parameters T, Pl, P2, tl and t2 are not specific to the present application and can be determined in a conventional manner by those skilled in mirror-welding processes.

[0057] This process of longitudinally welding the sheath elements 33, 34 yields, around the bundle of tendons 20, a sheath segment 31 whose geometrical configuration is quite similar to that of the original duct portion 21 (figure 9).

[0058] The clips can then be removed, and the braces 55, 56, 59, 60 separated from the sheath segment 31. At that time, the third and fourth braces 59, 60 may be removed from the assembly station, while the first and second braces 55, 56 may be kept for the subsequent steps, as shown in figure 9. Separation of the first and second braces 55, 56 is performed by means of the actuators 62 to leave a clearance between the inner surface 28 of the sheath segment 31 and the contour of the first and second braces 55-56. The sheath segment 31 can then be caused to slide upward along the stay cable.

[0059] If the newly formed sheath segment 31 is not the first one being assembled on the cable 10, it will then be joined to a previously formed sheath segment 31’ (figures 10-11) using a transversal welding tool 80. The transversal welding tool 80 is used to provide a butt-weld between the formed sheath segments 31, 31’, the jack system 64 applying pressures P3 and P4 for this butt-welding. In an embodiment, the joining is performed, for example, according to the following steps S1-S6:

[0060] SI: The shape of the lower end of the previously formed sheath segment 31’ is constrained to be in accordance with the desired circular cross-section of the sheath using a pneumatic cushion or radial hydraulic jacks (not shown) inserted between uppermost collar 52c and the lower end of the inner face of the sheath segment 31’. Optionally, an outer collar 74’ may be additionally used to apply an inward radial pressure to the bottom part of the outer face of the sheath segment 31’, as indicated by the arrows F’ in figure 10.

[0061] S2: The newly formed sheath segment 31 is pushed upwardly around the second collar 52b towards the third collar 52c. The sheath segment 31 is thus brought to the position shown in figure 10 where its upper transversal edge 36 is at the level of the third collar 52c, next to the lower transversal edge 36’ of the previously formed sheath segment 31’. The final part of the movement of the sheath segment 31 may be guided using a rail mechanism 75 adjacent to the third collar 52c.

[0062] S3: The shape of the newly formed sheath segment 31 is constrained to be in accordance with the desired circular cross-section of the sheath by the first and second braces 55, 56 which are pressed against the inner face 38 of the sheath segment 31 by controlling the actuators 62. Optionally, an outer collar 74 may be additionally used to apply an inward radial pressure to the bottom part of the outer face 37 of the sheath segment 31, as indicated by the arrows F in figure 10.

[0063] S4: The alignment of the transversal edges 36, 36’ of the sheath segments 31, 31’ is checked and, if needed, adjustments are made using one or more of the above-mentioned pneumatic cushion or radial hydraulic jacks, actuators 62 and collars 74, 74’.

[0064] S5: The sheath segment 31 is slightly moved down using the jack system 64 to leave space, e.g. of the order of 30 mm, for insertion of the transversal welding tool 80 illustrated in figure 11. The transversal welding tool may be a welding mirror consisting of a pair of semi-annular heating plates 80 introduced around the bundle of tendons 20 between the sheath segments, and heated to the temperature T suitable for locally melting the plastic material of the sheath segments 31, 31’ at their transversal edges 36, 36’.

[0065] S6: After introduction of the hot plates 80, the jack system 64 is controlled to bring the transversal edges 36, 36’ of the sheath segments 31, 31’ into contact with the plates 80 and apply a pressure P3 for a time t3 at the contacts between the transversal edges 36, 36’ and the plates 80. Thereafter, the jack system 64 is controlled to separate the sheath segments 31, 31’ in order to remove the heating plates 80, and to bring them again in contact along their molten transversal edges 36, 36’. The jack system 64 is then used to apply a pressure P4 for a time t4. The parameters T, P3, P4, t3 and t4 are not specific to the present application and can be determined in a conventional manner by those skilled in mirror-welding processes.

[0066] The sheath segments 31, 31’ can then be pushed upwardly to clear the working space 90 and thus allow assembly of a further sheath segment according to the same process as described above.

[0067] The above operations are repeated until the full length of the sheath is fabricated. If the existing sheath 26 has to be replaced on only part of its length, the remaining part of the existing sheath 26 forms the above-mentioned “previously formed sheath segment’’ 31’ when the first sheath segment 31 assembled from sheath elements 33, 34 is joined thereto.

[0068] It will be appreciated that the embodiments described above are illustrative of the invention disclosed herein and that various modifications can be made without departing from the scope as defined in the appended claims.