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Design Criteria Tower

STRUCTURAL ANALYSIS AND DESIGN FOR SELF SUPPORTING TOWER In compliance with the technical specification, the document describes the minimum criteria for specifying and designing of tower. I. STANDARD / REFERENCE a. TIA / EIA - 222 - STANDARD : Structural Standards for Steel Antenna Towers an d Antenna Supporting Structures. b. AISC-ASD Code ' 89 - American Institute of Steel Construction c. ACI 318-89 Code - American Concrete Institute d. Indonesian Loading Code ( PMI 1970 N.I-I8 ) II. MATERIALS SPECIFICATION a.Steel Structure - Structure Type = Self Supporting Tower - Steel Shapes & Plates = ASTM A 36 / JIS G3101 fy = 245 Mpa b.Bolt & Nut - Splice Bolts = ASTM A - 325 / JIS B1051 - Grade 8.8 fy = 560 Mpa c.Anchor Bolt - Grade of Anchor = ASTM A - 307 fy = 240 Mpa d.First Coating - Hot Dipped Galv. = ASTM A - 123 80 microns thickness e.Concrete - fc' = 19 Mpa ( 28 days ) / K-225 f.Rebars - Grade of rebars = BJTP ( dia. = 12 mm ) fy = 240 Mpa - Grade of rebars = BJTD ( dia. = 13 mm ) fy = 390 Mpa g.Welding Electrodes - Minimum Grade of Welding Electrode = AWS A5.1 E60XX. fy = 345 Mpa III. LOADINGS a.Dead Load Consist of Weight of Tower structure including antenna, ladder and appurtenances . b.Wind Load Calculated according to TIA / EIA - 222 - STANDARD : Structural Standard for Ste el Antenna Towers and Antenna Supporting Structures Maximum Wind Speed 120 Kph (3 Second Gust) and,Operational wind speed 84 Kph. Where wind force applied to each section of the structure shall be calculated fr om the equation : F = horizontal force applied to a section of the structure ( KN ) qz * GH * [ CF * AE + SCA*AA)], but not to exceed 2*qz*GH*AG

qz = Velocity pressure ( Pa ) = .613 Kz V2 for V in m/s Kz = Exposure Coefficient = [z/10]2/7 for z in meters 1.00 < Kz