b'WOOD AS DECKING COMPONENTS(a)Resistance 450 dynamic wind loading cycles. Small-400 361 363 scale specimens (16 x 16) were Fastener Pullout Resistance, lbf St. Dev/Average325 330 subjected to the same CSA A123.21 350 310 loading protocol. Data from over300 242 250 250240 240 200 small-scale specimens and wind 250 213 207 220 236 uplift resistance from over 20 full-scale 173 200 173 mock-ups were analyzed and200 summarized below.150 Small-scale fastener pullout resistance 100 data is summarized in Fig. 2, showing the superior performance of 5/8 50 plywood. This is valid, irrespective 0 of the fastener type/sources. Even by #14 #15 #14 #15 #14 #15 averaging the three sources, the OSB pullout resistance of #14 and #15 were, 5/8" OSB 1/2" Plywood 5/8" Plywood respectively, 182 and 221 lbf., which was lower than theplywood (235 and 243 lbf.). To determine which deck (b) Ratiosis suitable for wind uplift resistance, 25 ratios of the standard deviation over the average were calculated. Data showed 19.7 over 10-per-cent variations for the OSB; 20 in the case of the #14, the variation is as 15.7 much as 20 per cent. 15 Allowablelimit = 10% Fig. 3 shows the OSB performance 12.1 11.7 12.3 11.6 when used as a decking component 10.1 10.2 9.29.2 8.3 8.2 in the system and compared with the 10 7.1 7.7 steel deck. When the EPDM and TPO membranes were mechanically 5 fastened to the OSB deck, the system 0 0 0 could not sustain even the minimum 0 50psf requirement. One out of the two #14 #15 #14 #15 #14 #15 mock-ups tested with a narrower (36) mod bit membrane sustained a 60psf 5/8" OSB 1/2" Plywood 5/8" Plywood rating, whereas with the wider (120) PVC membrane, the sustained pressure FIGURE 2: FASTENER PULLOUT RESISTANCE FROM SMALL-SCALE TESTING. was about 50-per-cent lower when the Figure 2: Fastener pullout resistance from small scale testingdecking component was substituted with steel. Another equally important noted observation during the system 5/8" OSB SD testing was failure mode. Systems that 140 had OSB deck always failed due to 120 120 fastener pullout, irrespective of the membrane type. Thus, both small-scale Sustained Pressure, psf100 and system data revealed poor perfor-mance with OSB deck, and the data 80 75 75 75 had high variability with less probability 60 63 of repeatability. Based on this, it is not 60 recommended to use OSB as a deck 40 component in commercialroof applications.20 (Pt = 50 psf)(Pt = 50 psf)Respective small-scale and system 0 NRNRdata obtained fromplywood set is Mod. Bit. EPDM TPO PVC compared with the steel deck data in Fig. 4. Both the fastener pullout and 40 ksi 100 ksi wind uplift resistance are higher with steel deck compared to wood deck. Figure 3: Comparison of OSB vs. steel deck system performance FIGURE 3: COMPARISON OF OSB VS. STEEL DECK SYSTEM PERFORMANCE.Irrespective of the membrane type,18 BCBEC ELEMENTSA BCBEC PUBLICATION'