Loading...
HomeMy WebLinkAboutPROJECT INFORMATION: Job narrle Casfle Jobe 0915GM - SCANNED Installation company: GloMaster$igns. Installation location: 3525 W Midway Rd Ft. Pi--- Pi BY Section 3107 and 1609 of Florida Building Code 2010 applies: St. t_uCle County Chapter 29 of ASCE 7-10 (Wind Loads on Other Structures and Building Appurtances) applies: Type of structure: pylon sign Risk Category: I Ultimate design wind speed, figure C, FBC 2010, section 1609: 150 mph Wind stagnation pressure (qz) Table 1609.6.2 (1) FBC 2010 57.6 psf Design wind pressure conversion factor 0.77 Gust effect factor (G) ASCE 7-10 26.9.1 0.85 Widest part of sign face (B) 8.00 Height of sign face (s) 3.00 Overall height of sign (H) 8.00 Aspect ratio (B/s) 2.67 Clearance ratio (s/H) 0.38 Force Coefficient Cf from Figure 29.4-1, ASCE 7-10 1.4 Wind pressure (p) multiplied by design wind pressure conversion factor and Cf 52.8 psf 2. Calculate wind load and turning moments at base by the provisions of the alternate all -heights method in Section 1609.6. Wind shall be assumed to come from any horizontal direction and wind pressures shall be assumed to act normal to the surface considered. Hor Dim Vert Dim Fill Factor At p F H M (base) (ft) (ft) (so (Ibs) (ft) (ft-Ibs) 8.0 3.0 1.0 24.0 52.8 1267 6.5 8234 5.0 4.0 1.0 20.0 52.8 1056 2.0 2111 0.0 52.8 0 0 0.0 52.8 0 0 Total 44.0 2322 4.5 10345 3. Determine depth of embedment, D in feet From Table 1806.2, class 4, sandy soil, lateral bearing pressure below grade= 150 psf/ft Per 1806.3.4 Increase for poles, tabular value time 2 = 300 psf/ft Assume depth of hole (D) = 5 ft (Si) = 1500 psf - number of posts= 1 Load per post (P)= 2322 - from p. 5-81, Structural Engineering Handbook: D=((1.18`P)/(b'S1)p(1+(SQRT(1+(1.88`b'S 1 •H/P)))) assume b (ft)= 2 D (ft) = 4.1 Alternatively, Section 1807.3.2.1, Equation 18-1 A=2.34P/S1`b= 1.81 D=0.5A((1+(1+(4.36h/A))A0.5)= 4.0 feet 4. Determine required section modulus (inA3) at base max stress = (P•(H)'12)/section modulus max stress < allowable stress for outdoor signs, allowable stress < (0.66)(yield strength) steel grade A53grB yield strength 35000 psi required section > (P•(H)•12)/((0.66ys)) At base, minimum section modulus = 5.37 inA3 Use 6" SCH40 steel pipe, section modulus = 5.45 inA3 References: Structural Engineering Handbook, GaylordBGaylord editors, Fourth edition, McGraw Hill, NY 1997 ASCE 7 Florida Building Code 2007 with 2009 supplements . Mechanics of Materials, Beer and Johnston, McGraw Hill, NY 1981 ICBO Evaluation Report No. 4016 SBCCI Compliance Report No. 9368 Standard Handbook for Mechanical Engineers, T. Baumeister and L.S. Marks, editors, Seventh edition, McGraw Hill, NY 1967 John J Orlando PE 0044089 165 Old Ridge Road Macon GA 31211 (478) 784-2226 AA Na 0