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CALCULATIONS FOR FREESTANDING SIGNS <br /> QQ).. <br /> -Footing Design for Freestanding Signs and Flagpoles <br /> Structure Dimensions & Loading <br /> Design wind pressure: P= 24.7 psf <br /> Overturning Safety Factor: Q= 1.5 ...FBc 1807.2.3 <br /> Sign area 1: A1= 3.2 sq ft ...tributary area 1 for each footer(e.g.sign) <br /> Height of applied force above grade: h1= 3.2 ft ...height of area 1 centroid <br /> Sign area 2: A2 = 0.0 sq ft ...tributary area 2 for each footer(e.g.post) <br /> Height of applied force above grade: h2 = 0.0 ft ...height of area 2 centroid <br /> Overturning Moment: Mn= P*(A1*h1+A2*h2) <br /> Mn = 0.3 kip-ft <br /> Round Footing Diameter: B= 1.5 ft <br /> Footing depth: d = 2.67 ft Soil cover: ds= 0 ft <br /> Superstructure weight: Dr= 200 lb <br /> Soil cover weight: Ds= 0 lb =100pcf*n*B^2/4*ds <br /> Footing weight: Df= 708 lb ...=150pcf*n*B^2/4*d <br /> Total weight: D= 908 lb ...=Dr+Ds+Df <br /> Soil Strength ...FBc Tables 1806.2,1819.6 <br /> Soil class: 4.Sand,silty sand,silty gravel <br /> Lateral bearing strength: Plat= 150 psf/ft <br /> Vertical bearing strength: Pbrg= 2000 psf <br /> Check Lateral Soil Bearing Pressures (Empirical Method) ...FBc Sect 1807.3.2.1 <br /> Unconstrained (No rigid floor or pavement at ground surface) <br /> Allowable lateral soil bearing pressure at 1/3 depth: <br /> S1= 2*Plat * (d+ds)/3 <br /> S1= 267 psf <br /> Total applied lateral load: Ptot= 0.08 kips <br /> Equiv ht of applied load: heq = 3.20 ft <br /> As= 2.34*Ptot/(S1*B) <br /> As= 0.5 ft <br /> dreq= As/2 * [ 1+d(1+4.36*heq/As)] <br /> dreq= 1.53 ft dreq<d OK <br /> Page 3 <br />