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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: LE RESIDENCE <br />1006 S. AUSTIN STREET UNIT #2, SANTA ANA, CA 92704 <br />Rafter Loads: <br />Solar system dead load = 292 lbs / 8 lag bolts total = 36.5 lbs at each lag bolt <br />Existing roof dead load = 13 psf <br />Snow load = 0 psf <br />Roof live load = 20 psf <br />Wind load = 114.2 lbs, 587.5 lbs <br />Rafter span = 11.5 ft <br />Load Combinations That Apply: <br />#1: D + Lr or S = 13 psf + 36.5 lbs at each lag bolt + 20.0 psf <br />#2: D + 0.75(0.6W) + 0.75(Lr or S) = 13 psf + 36.5 lbs at each lag bolt) + (0.75 (0.6) 114.2 lbs at each lag bolt) + <br />(0.75 ( 20 psf)) <br />#3: 0.6D + 0.6W = 0.6 ( 13 psf + 36.5 lbs at each lag bolt) - (0.6) 587.5 lbs at each lag bolt <br />Calculated Maximum Bending Moment: <br />#1: 545.5 ft/lbs + 104.9 ft/lbs = 650.5 ft/lbs <br />[( 33 psf) ( 11.5 ft^2)] / 8 = 545.5 ft/lbs <br />[( 36.5 lbs) ( 11.5 ft)] / 4 = 104.9 ft/lbs <br />#2: 214.9 ft/lbs + 104.9 ft/lbs + 147.8 ft/lbs + 248.0 ft/lbs = 715.6 ft/lbs <br />[( 13 psf) ( 11.5 ft^2)] / 8 = 214.9 ft/lbs <br />[( 36.5 lbs) ( 11.5 ft)] / 4 = 104.9 ft/lbs <br />114.2 lbs) ( 11.5 ft)] / 4 = 147.8 ft/lbs <br />0.75 [( 20 psf) ( 11.5 ft^2)] / 8 = 248.0 ft/lbs <br />#3: 128.9 ft/lbs + 63.0 ft/lbs - 1013.5 ft/lbs = -821.6 ft/lbs <br />0.6 [( 13 psf) ( 11.5 ft^2)] / 8 = 128.9 ft/lbs <br />0.6 [( 36.5 lbs) ( 11.5 ft)] / 4 = 62.96 ft/lbs <br />0.6 [( 587.5 lbs) ( 11.5 ft)] / 4 = 1013.5 ft/lbs <br />Section Required: 821.6 ft/lbs (12) (0.7) / 1518 psi = 4.5 cu in <br />Section Provided: 1.5 ( 5.5 ^2) / 6 = 7.6 cu in <br />7.6 cu in > 4.5 cu in, OK <br />Calculated Deflection: <br />[5( 33 psf / 12) ( 138 in^4)] / [384 (1200000) ( 20.8 )] = 0.52 in <br />Allowable Deflection: 138 in / 240 = 0.58 in <br />0.58 in > 0.52 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 7/26/2022 Page 2 <br />1006 S Austin St <br />Unit 208/12/22