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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: PHAM RESIDENCE <br />2305 HUCKLEBERRY ROAD, SANTA ANA, CA 92706 <br />Rafter Loads: <br />Solar system dead load = 1194 lbs / 64 lag bolts total = 18.7 lbs at each lag bolt <br />Existing roof dead load = 20 psf <br />Snow load = 0 psf <br />Roof live load = 20 psf <br />Wind load = 65.7 lbs, 337.8 lbs <br />Rafter span = 11.0 ft <br />Load Combinations That Apply: <br />#1: D + Lr or S = 20 psf + 18.7 lbs at each lag bolt + 20.0 psf <br />#2: D + 0.75(0.6W) + 0.75(Lr or S) = 20 psf + 18.7 lbs at each lag bolt) + (0.75 (0.6) 65.7 lbs at each lag bolt) + <br />(0.75 ( 20 psf)) <br />#3: 0.6D + 0.6W = 0.6 ( 20 psf + 18.7 lbs at each lag bolt) - (0.6) 337.8 lbs at each lag bolt <br />Calculated Maximum Bending Moment: <br />#1: 605.0 ft/lbs + 51.3 ft/lbs = 656.3 ft/lbs <br />[( 40 psf) ( 11 ft^2)] / 8 = 605.0 ft/lbs <br />[( 18.65 lbs) ( 11.0 ft)] / 4 = 51.3 ft/lbs <br />#2: 302.5 ft/lbs + 51.3 ft/lbs + 81.3 ft/lbs + 226.9 ft/lbs = 662.0 ft/lbs <br />[( 20 psf) ( 11 ft^2)] / 8 = 302.5 ft/lbs <br />[( 18.65 lbs) ( 11.0 ft)] / 4 = 51.3 ft/lbs <br />65.7 lbs) ( 11 ft)] / 4 = 81.3 ft/lbs <br />0.75 [( 20 psf) ( 11 ft^2)] / 8 = 226.9 ft/lbs <br />#3: 181.5 ft/lbs + 30.8 ft/lbs - 557.4 ft/lbs = -345.1 ft/lbs <br />0.6 [( 20 psf) ( 11 ft^2)] / 8 = 181.5 ft/lbs <br />0.6 [( 18.65 lbs) ( 11.0 ft)] / 4 = 30.8 ft/lbs <br />0.6 [( 337.8 lbs) ( 11 ft)] / 4 = 557.4 ft/lbs <br />Section Required: 662.0 ft/lbs (12) (0.7) / 1518 psi = 3.7 cu in <br />Section Provided: 1.5 ( 5.5 ^2) / 6 = 7.6 cu in <br />7.6 cu in > 3.7 cu in, OK <br />Calculated Deflection: <br />[5( 40 psf / 12) ( 132 in^4)] / [384 (1200000) ( 20.8 )] = 0.53 in <br />Allowable Deflection: 132 in / 240 = 0.55 in <br />0.55 in > 0.53 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 3/22/2022 Page 2