SAMPLE PROJECT IN WASHINGTON DC DOCUMENT NO. CALC LOADS AND LOAD COMBINATIONS 9 PROJECT ENGINEER. Pages REVISION TITLE

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1 PROJECT DOCUMENT NO. CALC TITLE LOADS AND LOAD COMBINATIONS 9 ENGINEER REVISION Pages

2 LOADS AND LOAD COMBINATIONS 2 of 9 Table of contents 1 Basic Data References Loads Live load (L) Wind load (W) Cladding wind load on South Elevation Load combinations Factored load combinations Allowable stress design Factored load combinations - Strength design... 9

3 LOADS AND LOAD COMBINATIONS 3 of 9 1 Basic Data 1.1 References Norms and Standards [1] ASCE American Society of Civil Engineers Minimum Design Loads for Buildings and Other Structures Project documents Drawings [2] Murphy/Jahn Architects. S8.02 Typical Details and Structural Notes. 18 May 2012 [3] Murphy/Jahn Architects. A1.115 Roof Plan. 18 May 2012 [4] Murphy/Jahn Architects. A3.104 Elevation West. 18 May 2012

4 LOADS AND LOAD COMBINATIONS 4 of 9 2 Loads 2.1 Live load (L) Barrier load to curtain wall according to ASCE 7-10 clause 4.5, H L = 0.73 kn/m at 1067 mm above FFL Vertical concentrated load to maintenance walkway according to ASCE 7-10 Table 4-1, V L = 1.33 kn over an area of 0.58 m 2 BMU socket restraint load, H Lm = 1.0 kn in any direction 2.2 Wind load (W) Wind load calculation to ASCE 7-10 for components and cladding of partially enclosed building with occupancy category II on an exposure B terrain. V = 51 m/s Basic wind speed K zt = 1.00 Velocity pressure exposure coefficient K d = 0.85 Wind directionality factor h = 54.1 m K h =2.01(54.1/365.76) 2/7 = 1.16 Topographic factor [Table ] q h = = 1.57 kn/m 2 Velocity pressure [Cl ] Roof Plan 51 m 67 m 40 m 21 m 37 m

5 LOADS AND LOAD COMBINATIONS 5 of 9 Partial elevation h = 54.1 m z = 48.5 m z = 40.7 m z = 9 m

6 LOADS AND LOAD COMBINATIONS 6 of Wind load to main curtain wall A = 0.762m 3.20m = 2.44 m 2 Wind area considered (GCp) +/- = ±0.18 Internal pressure coefficient [Table ] i Positive pressure (Zone 4 & 5) z = 48.5 m K z =2.01(48.5/365.76) 2/7 = 1.13 Topographic factor [Table ] q z = = 1.53 kn/m 2 Velocity pressure [Cl ] (GCp) + = log(2.44)= External pressure coefficient [Fig ] p+ = 1.53(+0.87) 1.57(-0.18) = Cladding general pressure [Cl ] ii Non-corner negative pressure (Zone 4) (GCp) - = log(2.44) = External non-corner pressure coefficient [Fig ] p- = 1.57[-0.88 (+0.18)] = kn/m 2 Cladding general suction [Cl ] iii Corner negative pressure (Zone 5) a = max{0.1 37; 0.9} = 4.0 m Local corner zone (GCp) - = log(2.44) = External corner pressure coefficient [Fig ] p- = 1.57[-1.73 (+0.18)] = kn/m 2 Cladding corner suction [Cl ] Wind load to mechanical level A = 0.762m 2.11m = 1.61 m 2 Wind area considered (GCp) +/- = ±0.18 Internal pressure coefficient [Table ] i Positive pressure (Zone 4 & 5) z = h = 54.1 m (GCp) + = +0.9 External pressure coefficient [Fig ] p+ = 1.57[-0.9 (+0.18)] = kn/m 2 Cladding general pressure [Cl ] ii Non-corner negative pressure (Zone 4) (GCp) - = -0.9 External non-corner pressure coefficient [Fig ] p- = 1.57[-0.9 (+0.18)] = kn/m 2 Cladding general suction [Cl ] iii Corner negative pressure (Zone 5) a = max{0.1 37; 0.9} = 4.0 m Local corner zone (GCp) - = -1.8 External corner pressure coefficient [Fig ] p- = 1.57[-1.8 (+0.18)] = kn/m 2 Cladding corner suction [Cl ]

7 LOADS AND LOAD COMBINATIONS 7 of Wind load to external skin glazing (non-corner) Wind load to the non-corner area of the open-jointed point-fixed external skin glazing is calculated considering a partially enclosed building: A o > 1.1A oi A o > min{ 0.37 m 2 ; 0.01A g}; A oi/a gi 0.20 (GCp) +/- = ±0.55 Internal pressure coefficient [Table ] A = 3.05m 3.20m = 9.8 m 2 Wind area considered i Positive pressure (Zone 4 & 5) z = 40.7 m K z =2.01(40.7/365.76) 2/7 = 1.07 Topographic factor [Table ] q z = = 1.45 kn/m 2 Velocity pressure [Cl ] (GCp) + = log(9.8)= External pressure coefficient [Fig ] p+ = 1.45[+0.74 (-0.55)] = kn/m 2 Cladding general pressure [Cl ] ii Non-corner negative pressure (Zone 4) (GCp) - = log(9.8) = External non-corner pressure coefficient [Fig ] p- = 1.45[-0.80 (+0.55)] = kn/m 2 Cladding general suction [Cl ] Wind load to external skin glazing (corner) Wind load to the corner area of the open-jointed point-fixed external skin glazing is calculated considering parapet loading according to the procedures of ASCE 7-10 clause 30.9: A = 3.05m 3.20m = 9.8 m 2 Wind area considered i Corner negative pressure (Zone 5) a = max{0.1 37; 0.9} = 4.0 m Local corner zone (GCp) + = log(9.8)= External pressure coefficient [Fig ] (GCp) - = log(9.8) = External corner pressure coefficient [Fig ] p- = 1.45[-1.39 (+0.74)] = +/ kn/m 2 Cladding corner suction [Cl ]

8 LOADS AND LOAD COMBINATIONS 8 of Cladding wind load on South Elevation Wind loads for Ultimate Limit State Design* kn/m kn/m kn/m kn/m kn/m kn/m 2 +/ kn/m 2 +/ kn/m kn/m kn/m kn/m kn/m kn/m 2 Note: *Use reduction factor of 0.6 to determine wind loads for allowable stress design.

9 LOADS AND LOAD COMBINATIONS 9 of 9 3 Load combinations Load combinations for vertical cladding are in accordance with ASCE 7-10 [1]. 3.1 Factored load combinations Allowable stress design Combination Description CO100 (D) Dead load* CO101 (D) + 0.6(Wp) Dead + wind pressure loads CO102 (D) + 0.6(Ws) Dead + wind suction loads CO103 (D) + (L) Dead + imposed loads CO104 (D) (Ws) (L) Dead + wind suction + imposed loads CO104 (D) (Ws) (L) Dead + wind suction + imposed loads Note: *This includes permanent attachments and structural member selfweights. 3.2 Factored load combinations - Strength design Combination Description CO (D) Dead load* CO (D) + 1.0(Wp) Dead + wind pressure loads CO (D) + 1.0(Ws) Dead + wind suction loads CO (D) + 1.6(L) Dead + live loads CO (D) + 1.0(Ws) + 0.5(L) Dead + wind suction + live loads Note: *This includes permanent attachments and structural member selfweights.