STRUCTURAL ANALYSIS TYPICAL ANALYSIS - POLE LOCATION, ANTENNA SIZING AND SOILS PROPERTIES REQUIRED FOR SPECIFIC ANALYSIS.

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1 STRUCTURL NLYSIS TYPICL NLYSIS - POLE LOCTION, NTENN SIZING ND SOILS PROPERTIES REQUIRED FOR SPECIFIC NLYSIS. 9.5 FOOT BOVE GRDE, 1" DI. CONCRETE NTENN POLE WITH POLE TOP '-0" DIMETER BY 5'-6" CYLINDRICL EMS NTENN, ND (1) 5 SQ FOOT LUMINIRE ND 8 FOOT RM T 0 FEET. LSO ' WIDE BY 6' HIGH BNNER CENTERED T 6 FEET. PRESTRESSED CONCRETE POLE: BP00mm DI. X 9M : 9.5 FEET BOVE GRDE. LODING PER UNIFORM BUILDING CODE, 1997 WIND LODING: 70 MPH WIND ZONE ERTHQUKE LODING: ZONE 4, ESSENTIL FCILITY PREPRED MY 6, 00 PREPRED BY: MERON POLE PRODUCTS; STEVEN J. BULL, P.E. FOR: SOUTHERN CLIFORNI EDISON 1 OF 11

2 Structural Calculations for BP-00 x 9, (1' dia. x 9.5' above grade) pole: - 70 MPH Zone, Exposure C - Per Uniform Building Code, 1997 edition - (1) ' x 5.5' pole top, 500 LB top antennas and housing - (1) 5 square foot effective area luminaire arm and 0' - (1) 1" dia by 9.5' above grade concrete pole - (1) ' wide by 6' high banner, 6' above grade. Wind Loading: (Section 1618) F : ( area) P w I w C e C q where: area EP of component P w wind pressure 1.6 PSF I w wind importance factor 1.15 (UBC, table 16-K, essential facility) C e C q height, exposure, and gust factor coefficient (UBC, table 16-G 1.06 TO 1.) pressure coefficient (UBC, table 16-H (7), round lightpole (1.4)(/) STREETLIGHT LUMINIRE ND RM: POLE: ( 1in) ( 5.5ft) I e earthquake importance factor 1.5 (UBC, table 16-K, essential facility) POLE TOP antenna assembly: ( ) ( 1) 5ft 1ft 144in 1.6 lb ( 1.15) ( 1.1) ( 1.4) ft 1.6 lb ( 1.15) ( 1.) ( 1.4) ft 15 lb 97 lb 0'-15': ( 1in) ( 15ft) 1ft 1in 1.6 lb ( 1.15) ( 1.06) ( 1.4) ft 15 lb 15'-0': ( 1in) ( 15ft) 1ft 1in 1.6 lb ( 1.15) ( 1.) ( 1.4) ft 50 lb OF 11

3 BNNER: 1 ( ) ft6ft1.6 lb ( 1.15) ( 1.) ( 1.4) ft Working Moment at Groundline Due to Wind: 449 lb M w : ( 150) ( 157.5) ( 50.5) ( 4496) lbft M w BSE SHER: 5790lbft V base : ( ) lb V base 116 lb DED LOD MOMENT ( due to luminaire and mast arm): D : [ 50lb( 8ft 1.5ft) ] ( 0lb4ft) D 595 lbft DEFLECTION CLCULTIONS (pole top) T FULL WIND: δ : P a E c I ( ) 4 w p 8E c I where: P a : ( 1) lb Where pole weight is: w p : 100 lb ft P a 1 lb L a : 9.5ft 54 in E c lb : in I pole : 7516cm 4 from computer output I pole 901 in 4 DEFLECTION CLCULTIONS (pole top) T FULL WIND (cont'd): Estimated uniform load using worst case loading scenerio w ( ) lb 4 w p p : δ 1 : 9.5ft 8E c I pole P a E c I pole w p 5 lbft -1 δ 1 1.5in OF 11

4 Find moment due to p- W top : ( 500) lb therefore W top W pole 500 lb 1 : 100lbft 9.5ft P 1 : W top δ 1 W pole δ 1 P 1 5 lbft let P 1 P equiv : P equiv δ : E c I pole δ 0.0in ( ) P wind : W top δ 1 δ W pole ( δ 1 δ ) Required Ultimate Groundline Capacity: (Section 161): D 595 lbft (dead load) L : 0lbft (live load) M w 5790lbft (wind load) P wind 56 lbft (p-delta load) U w U w : 01.D 1. M w P wind fl L r 0.5( S) 457lbft ( ) Sec 161, Eq. 1-4 Pole Groundline Capacity: - use 400 mm pole section with (8) 9 mm prestressing wires M u : ( 6tonnem) (from computer output of equivalent pole section) M u 499lbft > 457 lb ft. Therefore, OK Pole adequate for required loading. 4 OF 11

5 CHECK ERTHQUKE LODING (Section 16 - Division IV): Seismic Zone 4 Non-Building Structure (table 16-I): Z 0.4 Occupancy Category 1 Facility type (table 16-k) I 1.5 Per section Top of antenna elev. H 5' < 65' Therefore use Static Force Proceedure Table 16-P (11) (self supporting structure) Table 16-P (11) (self supporting structure) Soil Profile Type (stiff soil profile) SD Distance to known seizmic source conservative < km (Orange County - by coast - maximum) - TYPE B fault R :.9 Ω 0 :.0 Table 16-S Near Source Factor conservative (< km) Table 16-T Near Source Factor conservative ( < km) N a : 1. N v : 1.6 Table 16-Q Seismic Factor Table 16-R Seismic Factor Design Response Spectra figure 16-): C a C v : : 0.44N a 0.64N v T s : C v.5c a T s 0.7 where: T o : 0.T s T o 0.14 W pole 950 lb W top : ( 500) lb W wires : 100lb W : W pole W top W wires W 550 lb Structure Period: s pole is not a building, the period shall be calculated as follows-- See "Formuls for Stress and Strain" by Roark, Table 6 Natural Frequencies of Members, Section b1. 5 OF 11

6 let W : 900lb 9.5ft w I pole : 7516cm 4 (from computer output) I pole 901 in 4 E c : lbin : W w 98lbft -1 ( ) f.5 E c Ig.5 n :.14 wl 4 f n : ( ) and 1 T : where f n.185 therefore T 0.46 f n seconds PER SECTION Z : 0.4 I e : 1.5 EQ (0-4) V : C v I e RT V I e EQ (0-5) V max :.5C a V max R ( ) EQ (0-6) V : 0.11C a I e V I e EQ (0-7) V : 0.8ZN v V 0.1 R PER SECTION OTHER NONBUILDING STRUCTURES: EQ (4-) V : 0.56C a I e V 0.4 I e EQ (4-) V : 1.6ZN v V R THEREFORE EQ. (0-5) GOVERNS, and: V : Therefore: V : VW V 1786 lb 6 OF 11

7 Section F t h x1 : : 0lb 7.5ft as period is less than O.7 sec, 9.5 h x : ft ( ) w x1 ( ) ( h x ) ( ) ( h x1 ) V F t h x1 F x : W pole W top W wires F t (0-15) where: sec 168.4, Eq. 8-8 W top W wires F top : W pole W top W wires F t ( ) ( V F t ) h x1 ( ) ( h x ) ( ) ( h x1 ) F top 491 lb F pole : ( W pole ) h x ( W pole ) V F t ( ) ( ) h x ( F t ) ( h x1 ) W top W wires F pole 195 lb DEFLECTION CLCULTIONS (pole top) DUE TO ERTHQUKE: 0 ft w pearth : ( F pole ) 4 w pearth δ e1 : 8E c I pole ( F top F t ) E c I pole w pearth 4.9lbft -1 δ e1 0.4ft Find moment due to p- therefore ( ) δ e1 P e1 : W top W wires W pole δ e1 P e1 495 lbft let P equiv : P e1 P equiv δ e : E c I pole δ e 0.05in 7 OF 11

8 P earth : W top W wires P earth 50 lbft ( ) ( ) δ e1 δ e W pole ( δ e1 δ e ) Check Groundline Moment due to Earthquake: E h E h E v : ( F t h x1 F top h x1 F pole h x ) : 61lbft P earth E : 1.0E h E v (eq. 0-1) E 115lbft Required Ultimate Groundline Capacity: (Section 161): D 595 lbft (dead load) L : 0lbft (live load) M w 5790lbft (wind load) P wind U w U w : 01.D 1. M w P wind fl L r 0.5( S) 56 lbft 457lbft (p-delta load) ( ) Sec 161, Eq. 1-4 check groundline earthquake load U e : 1.D 1.0( E) fl Sec 161.Eq. 1-5 U e 89lbft Pole Groundline Capacity: - use 00 mm pole section with (8) 9 mm prestressing wires M u : ( 6tonnem) (from computer output of equivalent pole section) M u 499lbft > 457 lb ft. Therefore, OK Pole adequate for required loading. 8 OF 11

9 NCHOR BOLT CHECK: Description: nchor Bolt Diameter: Number Threads per inch: (4) 1.5" -6 BOLTS on 15" BC D : n : 7 1.5in Bolt Circle: BC : 15in Where: F y : 6000lbin F v : 0.F y 1. F v 1464lbin Let Ft same ratio increase as allowed in SHTO Section F t : F v F t 940lbin 0. Cross-Sectional rea of Bolt: (Equation 5-) b π in : D b 0.97in 4 n Base Shear V base 116 lb Torsional wind load moment at pole base: T : ( ) ftlb T 0lb -1 ft -1 lbft Total Horizontal Force: F h : V base F h 116 lb F h Direct Shear Stress: f v : f v 9 lbin 4 b T Torsional Shear Stress: f vt : f vt 4 lbin 4 b BC Total Shear Stress (base): f vtotb : f v f vt f vtotb 55 lbin M w Direct Tensile Stress (base): f tb : f tb 189lbin b BC Formula -- Equation 5-4 : f vtotb F v f tb F t < 1.0 THEREFORE OK OF 11

10 TOP MOUNT BOLT CHECK: Description: nchor Bolt Diameter: Number Threads per inch: (4) / on 9.45" BC D : n : in Bolt Circle: Yield Strength of Steel: Cross-Sectional rea of Bolt: (Section , eq. 5-) bt BC t : F y 9.45in : 6000lbin π in : D bt 0.in 4 n llowable Tensile Stress: (Section , eq 5-1; Table -1) F t : 0.5F y 1. F t 940lbin llowable Shear Stress (Section , eq. 5-; Table -1) F v :.F y 1. F v 15800lbin Total Horizontal Force ( earthquake crit.): F he : F top F he 491 lb F he Direct Shear Stress: f v : 4 b f v 17 lbin Torsional Shear Stress: f vt : 0lb in f vt 0lbin Total Shear Stress: f vtot : f v f vt f vtot 17 lbin ( ) ft F he.75 Direct Tensile Stress: f t : b BC t f t 1770 lbin Formula -- Equation 5-4 : f vtot F v f t F t < 1.0 THEREFORE OK 0.01 CHECK FOUNDTION REQUIREMENTS: UNIFORM BUILDING CODE, 1997: Section NON-CONSTRINED FOOTING : LOD COMBINTION PER SECTION EQ 11 FOR LLOWBLE STRESS DESIGN. M glw : D M w M glw 5790lbft M gle : D E 1.4 M gle 654lbft Thus use wind loading: 10 OF 11

11 let: P : V base P 116 lb and: Ph : M glw.4p S 1 b and: h : M glw P d h 1 Ph thus: Ph 5790lbft h : h.7 ft P 116 lb P Design :.5' sq x 5' deep, weight 4000 pounds From Section , b diagonal measurement of base. Therefore: b :.5ft1.414 and d : 5ft S 1 : ( d) 00lbft.01. S lbft - (.4P) : 0.8 ft S 1 b 4.6h d reqd : 1 1 where: h 1 5ft Required d 5' equals 5' utilized, THEREFORE O.K. CHECK FOR LTERLLY CONSTRINED CONDITIONS: Section : CHECK.5" SQ X 4' DEEP FOUNDTION d : 4ft S : 00lbft S 18 lbft - d1. d reqd 4.5P S b h 0.5.8ft < 4ft THEREFORE OK Thus, for laterally constrained conditions, a.5' square by 4' deep foundation is adequate. 11 OF 11

2/23/ WIND PRESSURE FORMULA 2. PERCENT OF ALLOWABLE STRESS 3. FATIGUE DESIGN

2/23/ WIND PRESSURE FORMULA 2. PERCENT OF ALLOWABLE STRESS 3. FATIGUE DESIGN Original Title Presented by Northwest Signal copyright 2010 Designing & Building Structural Steel Products since 1976 Primary Users Traffic Signal Strain & Mast Arm Poles Cantilever & Bridge Sign Structures