Building methods

1. A method of building a portal frame structure, the method including the steps of:

(a) fabricating a first generally longitudinal, non-steel wall sub-structure of the portal frame structure with a first cable retainer attached to, or forming part of, the first wall sub-structure and that extends along a substantial portion of a longitudinal length of the first sub-structure;

(b) fabricating a second generally longitudinal, non-steel wall sub-structure of the portal frame structure with a second cable retainer attached to, or forming part of, the second wall sub-structure and that extends along a substantial portion of a longitudinal length of the second sub-structure;

(c) fabricating a generally longitudinal, non-steel centre span sub-structure of the portal frame structure with a third cable retainer attached to, or forming part of, the centre span sub-structure and that extends along a substantial portion of a longitudinal length of the centre span sub-structure;

(d) assembling the sub-structures first wall, second wall and centre span into the portal frame structure in an assembled configuration;

(e) inserting first, second and third cables into the first, second and third cable retainers respectively;

(f) after step (d), applying a tensile force to the first, second and third cables, relative to the first, second and third cable retainers respectively; and

(g) after step (f), bonding the first, second and third cables to the first, second and third cable retainers respectively,

wherein the first, second and third cable retainers are in the form of tubular members which follow a respective tensile line of resistance the first, second and third sub-structures are subjected to when loaded during intended use, at least a portion of at least one of the first, second and third cable retainers being coupled to and positioned outwardly beyond an external boundary surface of the respective sub-structure when in the assembled configuration, and wherein the first wall, second wall and centre span sub-structures do not substantially change shape or change positioning from the assembled configuration when tensile force is applied to the first, second and third cables in step (f), and at least one of the respective tensile lines of resistance is non-linear such that at least one of the first, second and third cable retainers follows a non-linear path.

2. A method of building a portal frame structure, the method including the steps of:

(a) fabricating a first generally longitudinal, non-steel wall sub-structure of the portal frame structure with a first cable retainer attached to, or forming part of, the first sub-structure and that extends along a substantial portion of a longitudinal length of the first sub-structure;

(b) fabricating a second generally longitudinal, non-steel wall sub-structure of the portal frame structure with a second cable retainer attached to, or forming part of, the second sub-structure and that extends along a substantial portion of a longitudinal length of the second sub-structure;

(c) fabricating a third generally longitudinal, non-steel centre span sub-structure of the portal frame structure with a third cable retainer attached to, or forming part of, the third sub-structure and that extends along a substantial portion of a longitudinal length of the third sub-structure;

(d) inserting first, second and third cables into the first, second and third cable retainer retainers respectively;

(e) after step (d), applying a tensile force to the first, second and third cables, relative to the first, second and third cable retainers respectively;

(f) after step (e), bonding the first, second and third cables to the first, second and third cable retainers respectively; and

(g) assembling the first wall sub-structure, the second wall sub-structure and the third centre span sub-structure into the portal frame structure,

wherein the first, second and third cable retainers are in the form of tubular members which follow a respective tensile line of resistance the first, second and third sub-structures are subjected to when loaded during intended use, at least a portion of at least one of the first, second and third cable retainers being coupled to and positioned outwardly beyond an external boundary surface of the respective sub-structure when in an assembled configuration, and wherein the first wall, second wall and centre span sub-structures do not substantially change shape when tensile force is applied to the first, second and third cables in step (e), and at least one of the respective tensile lines of resistance is non-linear such that at least one of the first, second and third cable retainers follows a non-linear path.

3. A method of strengthening, or reducing deflection of, a built portal frame structure in an assembled configuration comprising a first generally longitudinal, non-steel wall sub-structure, a second generally longitudinal, non-steel wall sub-structure and a third generally longitudinal, non-steel centre span sub-structure, the method including the steps of:

(a) attaching first, second and third cable retainers to the first, second and third sub-structures of the portal frame structure respectively, with the first, second and third cable retainers extending along a substantial portion of a longitudinal length of the first, second and third sub-structures respectively;

(b) inserting first, second and third cables into the first, second and third cable retainer retainers respectively;

(c) applying a tensile force to the first, second and third cables, relative to the first, second and third cable retainers respectively; and

(d) after step (c), bonding the first, second and third cables to the first, second and third cable retainers respectively,

wherein the first, second and third cable retainers are in the form of tubular members which follow a respective tensile line of resistance the first, second and third sub-structures are subjected to when loaded during intended use, at least a portion of at least one of the first, second and third cable retainers being coupled to and positioned outwardly beyond an external boundary surface of the built portal frame structure when in the assembled configuration, and wherein the first wall, second wall and centre span sub-structures do not substantially change shape or change positioning from the assembled configuration when tensile force is applied to the first, second and third cables in step (c), and at least one of the respective tensile lines of resistance is non-linear such that at least one of the first, second and third cable retainers follows a non-linear path.

4. The method as claimed in claim 1 , wherein the method includes inserting at least two cables into one or more of the first, second and third cable retainers.

5. The method as claimed in claim 1 , wherein the tensile force is applied to the cable by jacking.

6. The method as claimed in claim 1 , wherein the sub-structures are produced from I or T section beams or from tubular truss assemblies.

7. The method as claimed in claim 1 , wherein the sub-structures are in the form of I or T section beams having at least one web and at least one flange, and the respective cable retainer retainers are attached to the web of the respective beam.

8. The method as claimed in claim 7 , wherein the cables pass through the flange of the respective beam.

9. The method as claimed claim 1 , wherein the sub-structures are truss assemblies and the cable retainer retainers are each a tubular member integral with the respective truss assemblies.

10. The method as claimed in claim 1 , wherein the cable retainer retainers are attached to their respective sub-structures external the boundaries of their respective sub-structures.

11. The method as claimed in claim 1 , wherein the non-steel sub-structures include any one of: aluminum and other alloys; carbon fibre; plastics; ceramics; timber; or glass.

12. The method of claim 1 , wherein the portal frame structure has at least a 50% reduction in deflection when under load compared to a portal frame structure which does not include cables following tensile lines of resistance.

13. The method of claim 1 , wherein at least one of the first and second cable retainers extends at an angle relative to a longitudinal axis of the respective first and second sub-structures.

14. The method of claim 2 , wherein the portal frame structure has at least a 50% reduction in deflection when under load compared to a portal frame structure which does not include cables following tensile lines of resistance.

15. The method of claim 2 , wherein at least one of the first and second cable retainers extends at an angle relative to a longitudinal axis of the respective first and second sub-structures.

16. The method of claim 3 , wherein the portal frame structure has at least a 50% reduction in deflection when under load compared to a portal frame structure which does not include cables following tensile lines of resistance.

17. The method of claim 3 , wherein at least one of the first and second cable retainers extends at an angle relative to a longitudinal axis of the respective first and second sub-structures.