Reinforcing

1. A reinforcing bar comprising a shaft extending along a portion of the length of the bar and a termination extending along an end portion of the bar, the termination incorporating an engagement face incorporating locking formations thereon arranged to interfit with a complementary shaped termination to form an interlock arranged to accommodate axial loading, the locking formations comprising a plurality of spaced apart upstands extending transversely across the engagement face, and a plurality of recesses disposed between adjacent ones of the upstands, wherein, in use the upstands and recesses interfit with upstands and recesses disposed on the complementary shaped termination, wherein to facilitate proper mating of the terminations in forming an interlock an end upstand adjacent a terminal end of the bar is wider than the other upstands and an innermost recess is wider than the other recesses to receive an upstand of the shape of the end upstand.

2. The reinforcing bar according to claim 1 , wherein each upstand has a side wall extending between a bridging portion of the upstand, and a base portion of an adjacent recess.

3. The reinforcing bar according to claim 2 , wherein each side wall incorporates a bearing surface which is arranged to engage the complementary shaped termination in the interlock.

4. The reinforcing bar according to claim 3 , wherein each side wall includes a first transition region formed above the bearing surface and forms the intersection between the bearing surface and the bridging portion; and a second transition region extends from the bearing surface to the base portion, the side walls are configured so that the bearing surfaces of the upstands form the regions of contact in the interlock to accommodate loading applied in the longitudinal direction with no points of contact formed at the transition regions.

5. A termination for a reinforcing bar, the termination having a body extending in a longitudinal direction between opposite first and second ends, and an engagement face formed on the body, in use the first end is joined to an end of a reinforcing bar, and the engagement face incorporates locking formations thereon arranged to interfit with a complementary shaped termination to form an interlock arranged to accommodate loading applied in the longitudinal direction, the locking formations comprising a plurality of spaced apart upstands extending transversely across the engagement face, and a plurality of recesses disposed between adjacent ones of the upstands, wherein, in use, the upstands and recesses interfit with upstands and recesses disposed on the complementary shaped termination, wherein to facilitate proper mating of the terminations in forming an interlock an end upstand adjacent a terminal end of the bar is wider than the other upstands and an innermost recess is wider than the other recesses to receive an upstands of the shape of the end upstand.

6. The termination for a reinforcing bar according to claim 5 , wherein the termination is formed as a metal casting.

7. The termination for a reinforcing bar according to claim 5 , wherein the termination is shaped to form part of a reinforcing coupling and arranged to form an interlock with a complementary termination of identical shape to said termination.

8. The termination for a reinforcing bar according to claim 5 , wherein the locking formations are shaped so that the reaction force at the interlock under axial loading does not induce separation of the terminations.

9. The termination for a reinforcing bar according to claim 5 , wherein each upstand has a side wall extending between a bridging portion of the upstand, and a base portion of an adjacent recess.

10. The termination for a reinforcing bar according to claim 9 , wherein each side wall incorporates a bearing surface which is arranged to engage the complementary shaped termination in the interlock.

11. The termination for a reinforcing bar, the termination having a body extending in a longitudinal direction between opposite first and second ends, and a lateral engagement face formed on the body, in use the first end is joined to an end of a reinforcing bar, and the engagement face incorporates locking formations thereon arranged to interfit with a complementary shaped termination to form an interlock arranged to accommodate loading applied in the longitudinal direction,

wherein the locking formations comprise one or more upstands extending transversely across the engagement face and at least one recess disposed adjacent to at least one of the upstands, wherein, in use, the at least one upstand and the at least one recess interfit with at least one upstand and at least one recess disposed on the complementary shaped termination,

wherein each upstand has a side wall extending between a bridging portion of the upstand, and abase portion of an adjacent recess,

wherein each side wall incorporates a bearing surface which is arranged to engage the complementary shaped termination in the interlock,

wherein each side wall includes a first transition region formed above the bearing surface and forms the intersection between the bearing surface and the bridging portion; and a second transition region extends from the bearing surface to the base portion, the side walls are configured so that the bearing surfaces of the upstands form the regions of contact in the interlock to accommodate loading applied in the longitudinal direction with no points of contact formed at the transition regions.

12. Reinforcing comprising: a reinforcing bar extending along a portion of the length of the reinforcing; and a termination extending along an end portion of the reinforcing, the termination having a body extending in a longitudinal direction between opposite first and second ends, and a lateral engagement face formed on the body, the engagement face incorporates locking formations thereon arranged to interfit with a complementary shaped termination to form an interlock arranged to accommodate loading applied in the longitudinal direction, and wherein the termination is permanently bonded to the reinforcing bar,

wherein the locking formations comprise one or more upstands extending a the upstands,

wherein, in use, the at least one upstand and the at least one recess interfit with at least one upstand and at least one recess disposed on the complementary shaped termination,

wherein each upstand has a side wall extending between a bridging portion of the upstand, and a base portion of an adjacent recess and wherein each side wall incorporates a bearing surface which is arranged to engage the complementary shaped termination in the interlock and wherein each side wall includes a first transition region formed above the bearing surface and forms the intersection between the bearing surface and the bridging portion; and a second transition region extends from the bearing surface to the base portion, the side walls are configured so that the bearing surfaces of the upstands form the regions of contact in the interlock to accommodate loading applied in the longitudinal direction with no points of contact formed at the transition regions.

13. The reinforcing according to claim 12 , wherein the first end of the termination is permanently bonded to an end of the reinforcing bar so that the termination and the reinforcing bar are joined in end to end relation.

14. The reinforcing according to claim 12 , wherein a reference axis of the termination that extends between the first and second ends is aligned with an axis of the reinforcing bar.

15. The reinforcing according to claim 12 , wherein the termination is friction welded to the shaft.

16. The reinforcing according to claim 12 , wherein a first said upstand is wider in the longitudinal direction than a second said upstand.

17. A coupling for interconnecting first and second reinforcing bars, the coupling comprising:

first and second reinforcing bars, each reinforcing bar comprising a shaft extending along a portion of the length of the bar and a termination extending along an end portion of the bar, the termination incorporating an engagement face incorporating locking formations thereon arranged to interfit with a complementary shaped termination to form an interlock arranged to accommodate axial loading, the locking formations comprising a plurality of spaced apart upstands extending transversely across the engagement face, and a plurality of recesses disposed between adjacent ones of the upstands, wherein, in use, the upstands and recesses interfit with upstands and recesses disposed on the complementary shaped termination, wherein to facilitate proper mating of the terminations in forming an interlock an end upstand adjacent a terminal end of the bar is wider than the other upstands and an innermost recess is wider than the other recess to receive an upstand of the shape of the end upstand,

the engagement faces of the terminations of the first and second reinforcing bars being in opposing abutting relation with the locking formations of those terminations interfitting to form an interlock, and

a retaining device disposed around the interlock to retain the engagement faces in the opposing abutting relation to one another.

18. The coupling according to claim 17 , wherein the interlock extends along an axis and the locking formations are shaped so that the interlocks accommodate loading in the direction of that axis without inducing loading on the retaining device.

19. The coupling according to claim 17 , wherein the retaining device is in the form of a sleeve.

20. The coupling according to claim 17 , wherein the terminations of the first and second reinforcing bars are of identical shape.

21. The reinforcing bar according to claim 1 , wherein the bearing surfaces extend at an angle of within 10° of the perpendicular to the direction of interlock axis and more preferably within 5° of the perpendicular.

22. The reinforcing bar according to claim 1 , wherein the upstands are stepped downwardly along the engagement face towards the terminal end of the bar.