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LAG SCREW ANALYSIS <br />Loads <br />Wind Pressures qz = -39.90 psf <br />Solar Panel Load QD = 3 psf <br />Panel Length l = 6.825 ft <br />Panel Width b 3.3833 ft <br />Attachment Spacing s = 4 ft <br />Portrait <br />Tributary Area At = 13.65 ft2 <br />Wind Load P W = qz * At = -545 lbs <br />Dead Load P D = Q D * At = 40.95 lbs <br />Uplift Pa = 0.6 P D + 0.6 Pw = -302 lbs <br />Landscape <br />Tributary Area At = b * s = 6.7667 ft2 <br />Wind Load P W = qz * At = -270 lbs <br />Dead Load P D = Q D * At = 20.3 lbs <br />Uplift Pa = 0.6 P D + 0.6 Pw = -150 lbs <br />Lag Screw 5/16" x 5" <br />Specific Gravity of Lumber SG = 0.50 (Douglas Fir-Larch) <br />Diameter of Lag Screw D = 5/16 in <br />Withdraw Design /in 1800*SG 3/2 *D 3/4 = 266 lbs/in <br />Depth of Embedment lp = 2.50 in <br />Total Nominal Withdrawal Value W = W * l p = 665 lbs <br />Load Duration Factor CD = 1.6 <br />Withdrawal Design Value W' = W * C D = 1064 lbs <br />Demand Capacity Ratio DCR = Pa / W' = 0.28 < 1 OK <br />4410 W Celeste St <br />12/23/21