STRUCTURAL CALCULATIONS Chapter 5 examples …

1 CompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATECS12 Ver CALCULATIONSFORC hapter 5 examples20' eave height using MWFRS all heights procedure20' eave height using MWFRS <60' procedureGuide to Wind Load Provisions of ASCE 7-10 CompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED Search Code:ASCE 7 - 10 Occupancy:Occupancy Group =BBusiness Risk Category & Importance Factors:Risk Category =IIWind factor = factor = factor = Type of Construction:Fire Rating:Roof = hrFloor = hr Building Geometry:Roof angle ( ) / degBuilding length (L) ftLeast width (B) ftMean Roof Ht (h) ftParapet ht above ftMinimum parapet ht ft Live Loads: Roof0 to 200 sf: 20 psf200 to 600 sf: 24 - , but not less than 12 psfover 600 sf: 12 psfFloor:Typical Floor50 psfPartitions15 psfLobbies & first floor corridors100 psfCompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATE Wind Loads.

2 ASCE 7- 10 Ultimate Wind Speed115 mphNominal W ind mphRisk Category IIExposure CategoryCEnclosure BuildingInternal pressure+ (Kd) case case of roof GableTopographic Factor (Kzt)TopographyFlatHill Height (H) ftHalf Hill Length (Lh) ftActual H/Lh = H/Lh = Lh = ftFrom top of crest: x = ftBldg up/down wind?downwindH/Lh= = = = = = Mean Roof Ht:Kzt = (1+K1K2K3)^2 = Effect FactorFlexible structure if natural frequency < 1 Hz (T > 1 second).h = ftHowever, if building h/B < 4 then probably rigid structure (rule of thumb).B = fth/B = structure /z ( ) = ftG = Using rigid structure defaultRigid StructureFlexible or Dynamically Sensitive Structure = Frequency ( 1) = Hz =500 ftDamping ratio ( ) =0zmin =15 ft/b = = = , gv = = = ftN1= = = = = ftG = = = = = = TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATEE nclosure ClassificationTest for Enclosed Building: A building that does not qualify as open or partially for Open Building:All walls are at least 80% for Partially Enclosed > 4' or sfAoi / Agi NOBuilding is sfPartially EnclosedConditions to qualify as Partially Enclosed Building.

3 Must satisfy all of the following: Ao Ao > smaller of 4' or Ag Aoi / Agi :Ao = the total area of openings in a wall that receives positive external = the gross area of that wall in which Ao is = the sum of the areas of openings in the building envelope (walls and roof) not including = the sum of the gross surface areas of the building envelope (walls and roof) not including Factor for large volume partially enclosed buildings (Ri) :If the partially enclosed building contains a single room that is unpartitioned , the internal pressure coefficient may be multiplied by the reduction factor area of all wall & roof openings (Aog):0 sfUnpartitioned internal volume (Vi) :0 cfRi = adjustment to constant (caution - see code) :Altitude = 0 feetAverage Air Density = lbm/ft3 Constant = TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATEWind Loads - MWFRS all h (Enclosed/partially enclosed only)Kh (case 2) = = ftGCpi =+ pressure (qh) = psfridge ht = ftG = Angle ( ) = degL = ftqi = qhRoof tributary area - (h/2)*L:4588 sfB = ft(h/2)*B:3670 sfUltimate Wind Surface Pressures (psf)Wind Normal to RidgeWind Parallel to Ridge B/L = = = = +qiGCpiw/-qhGCpiDist.

4 *CpqhGCpw/ +qiGCpiw/ -qhGCpiWindward Wall (WW) table table belowLeeward Wall (LW) Wall (SW) Roof (LR) in windward roofWindward Roof neg press. to h/2* Roof pos press. to h* h to 2h* > 2h* *Horizontal distance from windward edgeWindward Wall Pressures at "z" (psf)Combined WW + LWWindward WallNormalParallelzKzKztqzGCpw/+qiGCpiw/ -qhGCpito Ridgeto Ridge0 to 15' 513 223 831 029 = :See figure in ASCE7 for the application of full and partial loading of the above wind pressures. There are 4 different loading (psf) psf (GCpn = + )Leeward psf (GCpn = )Windward roof overhangs ( add to windward roof pressure) psf (upward)CompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATEWind Loads - MWFRS h 60' (Low-rise Buildings) Enclosed/partially enclosed onlyKz = Kh (case 1) = Strip (a) = ftBase pressure (qh) = psfEnd Zone (2a) = ftGCpi = + 2 length = ftWind Pressure Coefficients CASE ACASE BSurfaceGCpfw/-GCpiw/+GCpiGCpfw/-GCpiw/+ Wind Surface Pressures (psf) parapet = psf (GCpn = + )Windward roof Leeward parapet = psf (GCpn = )overhangs = psf (upward)

5 Add to windward roof pressureHorizontal MWFRS Simple Diaphragm Pressures (psf)Transverse direction (normal to L)Interior Zone: Wall psfRoof psf **End Zone: Wall psfRoof psf **Longitudinal direction (parallel to L)Interior Zone: Wall psfEnd Zone: Wall psf** NOTE: Total horiz force shall not be less than that determined by neglecting roof forces (except for MWFRS moment frames).The code requires the MWFRS be designed for a min ultimateforce of 16 psf multiplied by the wall area plus an 8 psf forceapplied to the vertical projection of the roof. = degCompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATEL ocation of MWFRS Wind Pressure ZonesNOTE: Torsional loads are 25% of zones 1 - 6.

6 See code for loading 7 -99 and ASCE 7-10 (& later)NOTE: Torsional loads are 25% of zones 1 - 4. See code for loading 7 -02 and ASCE 7-05 CompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATEU ltimate Wind Pressures Wind Loads - Components & Cladding : h <= 60' Kh (case 1) = = ftBase pressure (qh) = psfa = ftMinimum parapet ht = ftGCpi =+ Angle ( ) = degType of roof = GableRoof GCp +/- GCpiSurface Pressure (psf)User inputArea10 sf50 sf100 sf10 sf50 sf100 sf208 sf500 sfNegative Zone Zone Zone All Zone Zone pressures in the table above assume an internal pressure coefficient (Gcpi) of soffit pressure equals adjacent wall pressure reduced by internal pressure of psfParapetqp = psfSurface Pressure (psf)User inputSolid Parapet Pressure 10 sf100 sf500 sf40 sfCASE A = pressure towards building (pos)CASE A : Interior zone: B = pressure away from bldg (neg) Corner zone.

7 B : Interior zone: zone: +/- GCpiSurface Pressure (psf)User inputArea10 sf100 sf500 sf10 sf100 sf500 sf15 sf208 sfNegative Zone Zone Zone 4 & TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED BYDATEU ltimate Wind Pressures Location of C&C Wind Pressure ZonesRoofs w/ 10 Walls h 60' Gable, Sawtooth andand all walls& alt design h<90'Multispan Gable 7 degrees &Monoslope roofsh > 60'Monoslope 3 degrees3 < 10 h 60' & alt design h<90'h 60' & alt design h<90'Monoslope roofs Multispan Gable & Hip 7 < 27 10 < 30 Gable 7 < 45 h 60' & alt design h<90'Sawtooth 10 < 45 h 60' & alt design h<90'Stepped roofs 3 h 60'& alt design h<90'h 60 & alt design h90 CompanyJOB TITLEC hapter 5 examplesAddressCity.

8 StateJOB BYDATECHECKED BYDATE Roof Design LoadsItemsDescriptionMultiplepsf (max)psf (min)RoofingMetal, copper, or tin Roof deck, , 22 roof joists & Glass roof board perx acoustical & ElecMech. & Dead Load this DL instead Load Load Wind (zone 2 - 100sf) LoadingD + Lr + ( *W + Lr) *D + *W + Lr + + + + Live Load ReductionRoof / deg0 to 200 sf: psf200 to 600 sf: 24 - , but not less than 12 psfover 600 sf: psf300 psf400 psf500 psfUser Input: 450 psfCompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED SUMMARYCode:ASCE 7 - 10 Live Loads:Roof0 to 200 sf: 20 psf200 to 600 sf: 24 - , but not less than 12 psover 600 sf: 12 psfTypical Floor50 psfPartitions15 psfLobbies & first floor corridors100 psfDead psfWind Design Data.

9 Ultimate Design Wind Speed115 mphNominal Design Wind CategoryIIMean Roof Ht (h) ftExposure CategoryCEnclosure BuildingInternal pressure Coef+ (Kd) Snow Loads:Design Uniform Roof Snow load= psfFlat Roof Snow LoadPf = psfBalanced Snow LoadPs = psfGround Snow LoadPg = psfImportance FactorI = Exposure FactoCe = Factor Ct = Factor Cs = Design Data:Risk Category =IIImportance FactorI = spectral response accelerationSs = = Class=DSpectral Response CoefSds = = Design Category=DBasic STRUCTURAL System= Building Frame SystemsSeismic Resisting System= Steel ordinary concentrically braced frameDesign Base Shear V = Response CoefCs = Modification FactorR = Procedure= Equivalent Lateral-Force AnalysisCompanyJOB TITLEC hapter 5 examplesAddressCity, StateJOB BYDATECHECKED SUMMARY- continuedComponent and cladding ultimate wind pressuresRoof Surface Pressure (psf) Area10 sf50 sf100 sfNegative Zone Zone Zone All Zone Zone soffit pressure equals adjacent wall pressure reduced by internal pressure of psfParapetSolid Parapet Pressure (psf)

10 Area10 sf100 sf500 sfCASE A: Interior zone zone B: Interior zone zone Pressure (psf)Area10 sf100 sf500 sfNegative Zone Zone Zone 4 &