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HomeMy WebLinkAboutPylon CALCSDESIGN CALCULATIONS FOR 7-ELEVEN #38944 Sign E: Pylon Sign Indrio Rd & Kings Hwy – Ft Pierce Index: Pg 1 Cover Pg 2 Wind Loads Pg 3 Footing Design Pg 4 Primary Support(s) Pg 5 Cast-In Anchors Bolts PE # 67382 Easy Seals Cert Auth # 31124 Engineer's signature and seal valid for pages 1 through 5 Mar 17 2020 Christian Langley GENERAL NOTES: 1.Design is in accordance with the Florida Building Code 6th Edition (2017) for use within and outside the High Velocity Hurricane Zone (HVHZ). 2.Wind loads have been calculated per the requirements of ASCE 7-10 as shown herein, except where noted otherwise. 3.These engineering calculations pertain only to the structural integrity of those systems, components, and/or other construction explicitly specified herein and/or in accompanying engineering drawings. The existing host structure (if any) is assumed to be in good condition, capable of supporting the loaded system. No warranty, either expressed or implied, is contained herein. 4.System components shall be as noted herein. All references to named components and installation shall conform to manufacturer's or industry specifications as summarized herein. 5.Where site conditions deviate from those noted herein, revisions may be required or a separate site-specific engineering evaluation performed. 6.Aluminum components in contact with steel or embedded in concrete shall be protected as prescribed in the 2015 Aluminum Design Manual, Part 1-A. Steel components in contact with, but not encased in, concrete shall be coated, painted, or otherwise protected against corrosion. 7.Engineer seal affixed hereto validates structural design as shown only. Use of this specification by contractor, et. Al, indemnifies and saves harmless this engineer for all costs & damages including legal fees & apellate fees resulting from deviation from this design. 1200 N Federal Hwy, #200 Boca Raton, FL 33432 Easy Seals .com Page 1 CALCULATIONS FOR FREESTANDING SIGNS ASCE 7-10 Design Wind Loads FREESTANDING SOLID SIGNS (ELEVATED) Building Specs V =150 mph Basic wind speed Risk Category 1 Structure Exposure C ASD Load Combo Coeff:0.6 Calculations α =9.5 3-sec gust speed power law exponent Kd =0.85 Directionality factor zg =900'Nominal ht. of atmos. boundary layer Kzt =1.0 Topographic factor G =0.85 Cf =1.85 Force Coefficient …Width / Height ratio = 0.2 to 10 SIGN HEIGHT DESIGN WIND PRESSURES Kh = Kzqz 15 ft ± 39.2 psf 0.85 24.9 18 ft ± 40.7 psf 0.88 25.9 20 ft ± 41.7 psf 0.90 26.5 30 ft ± 45.4 psf 0.98 28.9 35 ft ± 46.9 psf 1.01 29.8 40 ft ± 48.2 psf 1.04 30.7 45 ft ± 49.4 psf 1.07 31.4 50 ft ± 50.5 psf 1.09 32.1 55 ft ± 51.5 psf 1.12 32.8 60 ft ± 52.5 psf 1.14 33.4 70 ft ± 54.2 psf 1.17 34.5 80 ft ± 55.8 psf 1.21 35.5 90 ft ± 57.2 psf 1.24 36.4 100 ft ± 58.5 psf 1.27 37.2 110 ft ± 59.6 psf 1.29 37.9 120 ft ± 60.8 psf 1.32 38.6 130 ft ± 61.8 psf 1.34 39.3 140 ft ± 62.8 psf 1.36 39.9 150 ft ± 63.7 psf 1.38 40.5 175 ft ± 65.8 psf 1.42 41.8 200 ft ± 67.6 psf 1.46 43.0 250 ft ± 70.9 psf 1.53 45.1 150 mph - Exp ''C'' Elevated Signs W/Ht Ratio = 0.2 to 2.0 Page 2 CALCULATIONS FOR FREESTANDING SIGNS Footing Design for Freestanding Signs and Flagpoles Structure Dimensions & Loading Design wind pressure:P =45.4 psf Overturning Safety Factor:Ω =1.5 … FBC 1807.2.3 Sign area 1:A1 =49.6 sq ft … tributary area 1 for each footer (e.g. sign) Height of applied force above grade:h1 =13.0 ft … height of area 1 centroid Sign area 2:A2 =13.4 sq ft … tributary area 2 for each footer (e.g. post) Height of applied force above grade:h2 =10.0 ft … height of area 2 centroid Overturning Moment:Mn =P*(A1*h1+A2*h2) Mn =35.3 kip-ft Round Footing Diameter:B =3 ft Footing depth:d =7.83 ft Soil cover:ds =0 ft Superstructure weight:Dr =200 lb Soil cover weight:Ds =0 lb … = 100pcf*π*B^2/4*ds Footing weight:Df =8302 lb … = 150pcf*π*B^2/4*d Total weight:D =8502 lb … = Dr + Ds + Df Soil Strength …FBC Tables 1806.2, 1819.6 Soil class: Lateral bearing strength:Plat =150 psf/ft Vertical bearing strength:Pbrg =2000 psf Check Lateral Soil Bearing Pressures (Empirical Method)…FBC Sect 1807.3.2.1 Unconstrained (No rigid floor or pavement at ground surface) Allowable lateral soil bearing pressure at 1/3 depth: S1 =2*Plat * (d+ds)/3 S1 =783 psf Total applied lateral load:Ptot =2.86 kips Equiv ht of applied load:heq =12.36 ft As =2.34*Ptot/(S1*B) As =2.8 ft dreq =As/2 * [ 1 + √(1+4.36*heq/As) ] dreq =7.78 ft dreq < d OK 4. Sand, silty sand, silty gravel Page 3 CALCULATIONS FOR FREESTANDING SIGNS Hollow Structural Rectangular Tubing in Bending Allowable Stress Design per 2010 AISC Spec for Structural Steel Buildings Material Properties Yield Stress, A500 Grd B Steel:Fy =46 ksi Safety Factor =1.67 Per Section B3.4 Modulus of Elasticity:E =29000 ksi Member Properties Flange:b =8 in Moment of Inertia:Ix =72.7 in4 Flange Thickness:tf =1/4"= 0.233''Section Modulus:S =18.2 in3 Web:d =8 in Deflection Limit:Defl =L / 80 Web Thickness:tw =1/4"= 0.233''End Supports:Cantilever Design wind pressure:P =45.4 psf Sign area:A1 =63.0 sq ft … tributary area for each post (e.g. sign+post) Eccentricity of applied force:e1 =12.4 ft … distance to area centroid (weighted avg h1,h2) Unbraced Length:Lc =12.4 ft Check for Limiting Width-Thickness Ratios (Compact/Noncompact, per Table B4.1) Flanges Webs b/t =32.4 = (b-2*t2)/t1 d/t =32.4 = (d-2*t1)/t2 1.12*√(E/Fy) =28.1 Flange Compact Limit 2.42*√(E/Fy) =60.8 Web Compact Limit 1.40*√(E/Fy) =35.2 Flange NonCompact Limit 5.70*√(E/Fy) =143.1 Web NonCompact Limit Flanges are noncompact Webs are compact (1): Yielding Limit State This criteria applies to all members, compact and noncompact Mn =Fy*S Mallow = Mn / 1.67 Mn =836.1 kip-in Mallow = 500.7 kip-in Check Member Bending Allowable Moment:Mn =500.7 kip-in Minimum of Mallow values above Moment in member:Mmax =P*A1*e1 Mmax =423.9 kip-in Mmax < Mn …OK Check Member Deflection: Allowable Deflection:∆allow =1.85 in L / 80 Deflection in member:∆max =P*(A*e^3) / (3*E*I) ∆max =1.47 in ∆max < ∆allow …OK Page 4 CALCULATIONS FOR FREESTANDING SIGNS Cast-in-Place Concrete Anchor Bolts ACI 318-11, Appendix "D" Required Strength: Wind pressure:W =45.4 psf Tributary area:A =63.0 sqft Dead load:D =0 lb Load eccentricity:e =12.4 ft ASCE 7-10, 2.3.2: U =(1.2)D + (1.0)W Mu =58.88 kip-ft … = [(1.2)D+(1.0)W]*A*e Anchor & Concrete Specs:Concrete:f'c =2500 psi Anchor bolt size:1-1/4"da =1.25 in nt =7 threads/in Anchor material:futa =74 ksi Embedment:hef =30 in Edge distance:ED =12 in Qty anchors in group:Q =2 anchors Anchor group offset:a =12 in Anchor Strength:Steel:φs =0.75 Tension:U ≤0.75 φ Nn φc =0.70 Steel Strength: Ase =π/4*(da-0.9743/nt)²Nsa =Ase*futa Ase =0.97 in²Nsa =71.7 kips φs*Nsa =53.8 kips Concrete Breakout: Anc =[ED+s+1.5*hef]*[ED+1.5*hef]Anco =9*hef^2 Anc =3249 in²Anco =8100 in² Nb =kc*λ*√f'c*hef^1.5 Ψc =1.0 Nb =197.2 kips Cast-in anchors:Ψcp =1.0 Ψed = 0.7 + 0.3*ED/(1.5*hef)Ψed =0.78 kc =24 …cast-in anchors No eccentricity between anchors:Ψec =1.0 λ =1.0 … normal weight concrete Concrete breakout strength:Ncb =(Anc/Anco)*Ψc*Ψcp*Ψed*Ψec*Nb Ncb =61.7 kips φc*Ncb =43.2 kips Concrete Pullout: Head diameter: dh =3 in Np =8*Abrg*f'c Abrg =7.1 in² Np =141.4 kips Cracked Concrete:Ψc,p =1.0 Concrete pullout strength:Npn =Ψc.p*Np Npn =141.4 kips φc*Npn =99.0 kips Concrete Blowout: Headed Stud / Bolt:Nsb =160*ED*√Abrg*λ*√f'c Concrete blowout strength:Nsb =255.2 kips φc*Nsb =178.7 kips Critical Anchor Strength: φNn =min(φs*Nsa,φc*Ncb,φc*Npn,φc*Nsb)φNn =43.2 kips φMn =Q*φNn*a φMn =86.4 kip-ft Mu ≤0.75 φ Mn 64.8 kip-ft OK SAE Grade 2 / A307 Conc, no suppl reinf: Cracked Concrete: Headed Stud / Bolt: 58.88 kip-ft < Page 5