Improvements in the Deformation Resistance of Timber Frame Partitions

Abstract

A partition for a building structure comprises a support frame and a plasterboard affixed to the support frame. The support frame comprises a plurality of elongate timber members. The plasterboard comprises a gypsum matrix having fibres embedded therein in an amount of at least 1 wt % relative to the gypsum, as well as a polymeric additive that is present in an amount of at least 1 wt % relative to the gypsum.

Claims

1. A partition for a building structure, the partition comprising a support frame and at least one plasterboard affixed to the support frame, wherein: the support frame comprises a plurality of elongate timber members; and the plasterboard comprises a gypsum matrix having fibres embedded therein in an amount of at least 1 wt % relative to the gypsum, the gypsum matrix further comprising a polymeric additive that is present in an amount of at least 1 wt % relative to the gypsum.

2. The partition of claim 1, wherein the fibres are present in an amount of at least 3 wt % relative to the gypsum.

3. The partition of claim 1, wherein the polymeric additive is present in an amount of at least 3 wt % relative to the gypsum.

4. The partition of claim 3, wherein the polymeric additive is present in an amount of at least 5 wt % relative to the gypsum.

5. The partition of claim 1, wherein the fibres are present in an amount of about 3 wt % relative to the gypsum and the polymeric additive is present in an amount of about 5 wt % relative to the gypsum.

6. The partition of claim 1, wherein the plasterboard has a backing lamina attached to one of the faces thereof.

7. The partition of claim 6, wherein the backing lamina has a thickness greater than 1 mm.

8. The partition of claim 6, wherein the backing lamina is a fibreglass lamina.

9. The partition of claim 1, wherein the fibres are glass fibres.

10. The partition of claim 9, wherein the fibres have an average length less than 12 mm.

11. The partition of claim 10, wherein the fibres have an average length less than 10 mm.

12. The partition claim 1, wherein the polymeric additive is a starch.

13. The partition of claim 1, wherein the polymeric additive is polyvinyl acetate.

14. The partition of claim 1, having a racking stiffness, measured in accordance with British standard BS EN 594:1996, that is greater than 1500 N/m.

15. The partition of claim 14, wherein the racking stiffness is greater than 2000 N/m.

16. A partition for a building structure, the partition comprising a support frame and at least one plasterboard affixed to the support frame, wherein: the support frame comprises a plurality of elongate timber members; and the plasterboard comprises a set uncalcined gypsum plaster matrix having fibres embedded therein in an amount of at least 1 wt % relative to the set uncalcined gypsum plaster matrix, the set uncalcined gypsum plaster matrix further comprising a polymeric additive that is present in an amount of at least 1 wt % relative to the set uncalcined gypsum plaster matrix.

17. The partition of claim 16, wherein the fibres are present in an amount of about 3 wt % relative to the gypsum and the polymeric additive is present in an amount of about 5 wt % relative to the gypsum.

18. The partition of claim 16, wherein the fibres have an average length less than 12 mm.

19. The partition of claim 16, wherein the polymeric additive is at least one of starch and polyvinyl acetate.

20. The partition of claim 16, wherein the plasterboard has a racking stiffness, measured in accordance with British standard BS EN 594:1996, that is greater than 1500 N/m.

Description

DETAILED DESCRIPTION

[0018] The invention will now be described by way of example with reference to the following Figures in which:

[0019] FIG. 1 shows a schematic elevation view of a test apparatus for measuring racking resistance.

TESTING RACKING RESISTANCE OF BOARDS

[0020] Racking resistance was measured in accordance with British standard BS EN 594:1996.

[0021] Referring to FIG. 1, a 2400 mm high×2400 mm long test specimen 10 was constructed and placed within the test rig. The test specimen comprised a frame consisting of 90 mm×38 mm cross-section timber top and bottom rails, and 90 mm×38 mm cross-section timber studs extending therebetween at 600 mm intervals. A head binder 12 was rigidly attached to the top and bottom rails. The test specimen was bolted into the test rig by means of bolts 13 inserted through the bottom rail of the frame.

[0022] Plasterboard sheathing 14 was fixed to the frame in a single layer below the head binder. The boards were screw fixed with 41 mm British Gypsum drywall timber screws at 300 mm intervals around the perimeter of the boards.

[0023] In a first loading step, a downward vertical pre-load F.sub.v was applied to the test specimen at the positions of the studs. This load was subsequently removed. In a second loading step, a racking load F was applied horizontally to the top of the test specimen onto a metal plate 16 attached to the top rail of the panel and the head binder. The deformation d of the board was measured as the displacement at transducer A minus the displacement at transducer B.

[0024] The racking stiffness is calculated as the ratio of racking load F to the deformation d of the board.

EXAMPLES

Example 1

[0025] A plasterboard having a gypsum core containing the following additional components: [0026] 3 wt % 6 mm glass fibre [0027] 6 wt % starch (a mixture of Amidon MB065X from Roquette and Coatmaster K57 ethylated starch from Grain Processing Corporation) [0028] a water-resistant additives: silicone oil and cement [0029] biocide: sodium omadine

[0030] The board has a thickness of 12.5 mm and a weight of 12.3 kg/m.sup.2.

[0031] The board has a liner provided by a pre-coated glass mat having a weight of 360 g/m.sup.2 and a mineral coating.

Example 2

[0032] A plasterboard having a gypsum core containing the following additional components: [0033] 3wt % of 12 mm glass fibre [0034] 3wt % starch (a mixture of Amidon MB065X from Roquette and Coatmaster K57 ethylated starch from Grain Processing Corporation)

[0035] The plasterboard has a paper liner on both sides of the board, the liner having a weight of 240 g/m.sup.2, and additionally a backing lamina provided by a 1.5 mm fibre glass sheet. The total thickness of the composite board (including the gypsum board and the backing lamina) is 15 mm. The total weight of the composite board is 15.6 kg/m.sup.2.

Example 3

[0036] A plasterboard having a gypsum core containing the following additional components: [0037] 3 wt % of 6mm glass fibre; and [0038] 5 wt % starch (Merifilm starch from Tate & Lyle).

[0039] The plasterboard has a paper liner on each side of the board. The weight of the paper liner is 190 g/m.sup.2 on the side of the board facing away from the support frame and 180 g/m.sup.2 on the side of the board facing towards the support frame. It is 12.5 mm thick product with a weight of approx. 12 kg/m.sup.2.

Comparative Example 1

[0040] A plasterboard having a gypsum core containing the following additional components: [0041] 0.5 wt % of 12 mm glass fibres

[0042] The board has a liner provided by a pre-coated glass mat. The weight of the board is 11 kg/m.sup.2.

[0043] Results

TABLE-US-00001 Mean racking Mean racking Example stiffness strength Failure mode 1 2426 N/mm 8726 N 2 studs detached from rail 2 3108 N/mm 14044 N  3 studs detached from rail 3 3652 N/mm 9989 N 2 studs detached from rail Comparative 1122 N/mm 4666 N Screws pulled through example 1 board