2001 ASD Supplements - unprotected PDF - American Wood Council

SW-28APPENDICESBased upon the sheathing panel layout as shown, thediaphragm is Case 1 for the N-S direction and Case 3 forthe E-W direction. The shear capacities for wind loadingper Table 3.1A and seismic load per Table 3.1B (in parentheses)are:PanelGradeRatedSheathingCommonNailMin.Penetrationin Framing(in.)Min.PanelThickness(in.)Min.FramingMemberWidth(in.)8d 1-3/8 15/32 2 380x.93Blocked Diaphragm(lb./ft.)Nail SpacingBoundary/Other EdgesUnblockedDiaphragm(lb./ft.)6/6 4/6 2.5/4 2/3 Case 1 Case 2∼6(270) 505 (360) 740 (530) 840 (600) 335 (240) 250x.93 x.93 x .93 x .93 x .93 x .93 x .93 x .93 x .93 x .93Shear Capacities for Hem-Fir Framing Members: 353 (251) 470 (335) 688 (493) 781 (558) 311 (223) 233 (167)Note that the table values are only valid for framing members (including blocking) with specific gravity greater than 0.49. For framing members withspecific gravity greater than or equal to 0.42 but less than 0.49 such as Hem-fir (specific gravity = 0.43), a factor of (1-(0.50 - 0.43)) = 0.93 must beapplied to the table values.(180)x .93• N-S Direction: (Wind)Below is the shear distribution along the length of the building. Plotting the shear distribution aids in optimizing thenailing (and blocking) along the length of the diaphragm. For a Case 1 unblocked diaphragm, the maximum shearcapacity for wind is 311 plf. As 311 plf is greater than 280 plf, blocking is not required for wind in this direction.APA – The Engineered Wood Association