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STRUCTURAL ANALYSIS FOR NEW PHOTOVOLTAIC SOLAR SYSTEM <br />NOTE: <br />THESE CALCULATIONS ARE BASED ON INFORMATION AND MEASUREMENTS PROVIDED BY THE CONTRACTOR FROM <br />HIS SITE INSPECTION. <br />3 Analysis of Existing Rafter Capacity:PV SOLAR ARRAY: KNUTH RESIDENCE <br />1006 N. LOWELL STREET, SANTA ANA, CA 92703 <br />Rafter Loads: <br />Solar system dead load = 759 lbs / 20 lag bolts total = 37.9 lbs at each lag bolt <br />Existing roof dead load = 12 psf <br />Snow load = 0 psf <br />Roof live load = 20 psf <br />Wind load = 118.8 lbs, 611.0 lbs <br />Rafter span = 7.5 ft <br />Load Combinations That Apply: <br />#1: D + Lr or S = 12 psf + 37.9 lbs at each lag bolt + 20.0 psf <br />#2: D + 0.75(0.6W) + 0.75(Lr or S) = 12 psf + 37.9 lbs at each lag bolt) + (0.75 (0.6) 118.8 lbs at each lag bolt) + <br />(0.75 ( 20 psf)) <br />#3: 0.6D + 0.6W = 0.6 ( 12 psf + 37.9 lbs at each lag bolt) - (0.6) 611.0 lbs at each lag bolt <br />Calculated Maximum Bending Moment: <br />#1: 225.0 ft/lbs + 71.1 ft/lbs = 296.1 ft/lbs <br />[( 32 psf) ( 7.5 ft^2)] / 8 = 225.0 ft/lbs <br />[( 37.93 lbs) ( 7.5 ft)] / 4 = 71.1 ft/lbs <br />#2: 84.4 ft/lbs + 71.1 ft/lbs + 100.2 ft/lbs + 105.5 ft/lbs = 361.2 ft/lbs <br />[( 12 psf) ( 7.5 ft^2)] / 8 = 84.4 ft/lbs <br />[( 37.93 lbs) ( 7.5 ft)] / 4 = 71.1 ft/lbs <br />118.8 lbs) ( 7.5 ft)] / 4 = 100.2 ft/lbs <br />0.75 [( 20 psf) ( 7.5 ft^2)] / 8 = 105.5 ft/lbs <br />#3: 50.6 ft/lbs + 42.7 ft/lbs - 687.4 ft/lbs = -594.1 ft/lbs <br />0.6 [( 12 psf) ( 7.5 ft^2)] / 8 = 50.6 ft/lbs <br />0.6 [( 37.93 lbs) ( 7.5 ft)] / 4 = 42.7 ft/lbs <br />0.6 [( 611.0 lbs) ( 7.5 ft)] / 4 = 687.4 ft/lbs <br />Section Required: 594.1 ft/lbs (12) (0.7) / 1518 psi = 3.3 cu in <br />Section Provided: 1.75 ( 3.75 ^2) / 6 = 4.1 cu in <br />4.1 cu in > 3.3 cu in, OK <br />Calculated Deflection: <br />[5( 32 psf / 12) ( 90 in^4)] / [384 (1200000) ( 7.7 )] = 0.25 in <br />Allowable Deflection: 90 in / 240 = 0.38 in <br />0.38 in > 0.25 in, OK <br />NOTICE: VISION CIVIL ENGINEERING: JENNIFER KEMME, PE <br />ANY CHANGES TO OR USES OF THESE DOCUMENTS 12273 11TH STREET, YUCAIPA, CA 92399 <br />WITHOUT THE WRITTEN CONSENT OF VISION 909.754.8300, JENKEMME@VISIONCE.COM <br />CIVIL ENGINEERING IS STRICTLY PROHIBITED. RCE 73054, EXP 12/31/22 <br />0.75 [(0.6)( <br />Prepared by JENNIFER KEMME 7/3/2022 Page 2 <br />1006 N Lowell <br />Street08/11/22