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DESIGN MANUAL& KEYWALL OPERATING GUIDEBNCMA 2ND EDITION - COULOMB METHODOLOGY LEVEL SURCHARGE - 250 PSF12) Pullout ResistancePullout safety factors are determined on a level by level basis. The effective lengths and calculatedpullout is determined at each level and compared to a safety factor of 1.5.q for maximum stress, bearing pressureZL e = 2.33'SG200H = 10'L e = 3.97'SG200ρ = 58.4˚L e = 5.60'L e = 6.84'SG200SG2001.75L = 7.25'B = 9.0'LEVEL BY LEVEL PULLOUT ANALYSISCheck each grid level for available pullout resistance against previously calculated tensile loads,Surcharge is not considered as a resisting force under NCMA guidelines:Pullout Resistance = (γH ov ) (2L e ) (Tan(φ)C i ) with H ov = average height of over burden.L e = (L - Height ⁄ Tan ρ)Height Grid Hov γ Le Tan34 Ci Pullout Load FS po4) 8.00' SG200 2.00 120 2.33 .674 0.90 679 353 1.923) 5.33' SG200 4.67 120 3.97 .674 0.90 2701 507 5.332) 2.67' SG200 7.33 120 5.60 .674 0.90 5980 608 9.841) 0.67' SG200 9.33 120 6.84 .674 0.90 9298 528 17.61OK - All pullout safety factors are greater than 1.5.B.7