Fine testing
Tests are continuing. Fire tests on this material were performed for the Owens-Corning Fiberglas Corporation. The test results are summarized as follows:
1 ASTM E-84 tunnel test and 'Life Safety Code' NFPA-101 surface burning characteristics:
Flame spread -5
Smoke developed -5
Fuel contributed -5
2 Standard Method of Test of Non-combustibility of Elementary Materials, ASTM E-136-65:
The material was rated 'non-combustible'. The recorded temperatures of the interior and surface thermocouples did not at any time during the test rise above the 750 degree C starting temperature of the furnace.
3 ASTM Specification E-108 and Underwriters' Laboratory Standard UL-790:
This test contained three parts: A, Intermittent Flame Exposure Test; B, Spread of Flame Test; and C, Burning Brand Test. The test deviated from the standard procedure since the roof covering was supported by a positive air pressure rather than the wooden decks described in the ASTM Standard E-108 or UL-790. Pressure varied from 25.4 mm (1 in) of water at the beginning of the test and, because of leaks, it reduced at times to 6.35 mm (.25 in) of water. Temperatures reached were from 760 degrees C for Test A and B to 1204 degrees C for Test C. The results indicated that this Teflon Coated Fiberglas air-supported roof covering will satisfactorily withstand the three methods of test in ASTM E-108 and UL-790 when tested for a Class B rating.
For a non air-supported structures these identical tests were run for a composite construction consisting of Teflon coated glass cloth and 50.8 mm (2 in) of Fiberglas flexible insulation with a white vinyl-reinforced-foil vapor barrier facing. These test results also established a Class B rating.
The straightness of the fibers in the warp direction accounts for the linear stress strain curve which mirrors the physical properties of the straight yarn. On the other hand, the fill fibers are kinked around these and must straighten and consequently kink the warp fiber before exhibiting the linear stress-strain characteristics of the base yarn. For bi-axial loading, the stress strain characteristics are non-linear,non-isotropic and vary according to previous stress history.
For fabric structures which are not cable reinforced it is necessary to introduce the elastic properties of the fabric in the structural analysis; while for cable-reinforced structures, the stiffness of the fabric is negligible compared to that of the cables, and the cable stiffness alone is used. The fabricator then accounts for the elastic properties of the fabric in patterning and fabricating the individual panels.