STRUCTURAL CALCULATIONS FOR SUSPENDED BUS SYSTEM SEISMIC SUPPORTS SEISMIC SUPPORT GUIDELINES

Customer: PDI, 4200 Oakleys Court, Richmond, VA 23223 Date: 5/31/2017 A. PALMA e n g i n e e r i n g Tag: Seismic Restraint Suspended Bus System Supports Building Code: 2012 IBC/2013 CBC&ASCE7-10 STRUCTURAL CALCULATIONS FOR SUSPENDED BUS SYSTEM SEISMIC SUPPORTS SEISMIC SUPPORT GUIDELINES PROJECT: REVISION 0 Original Calculations Dated 05/30/17 CALCULATIONS PREPARED BY: A. PALMA ENGINEERING P.O. Box 1075, Pleasanton, CA 94566 Tel (925) 469-0417, Fax (925) 469-0462 For Office Use Only: Busrail busway bus system Unistrut - 2013cbc.xmcd C:\Users\TUNG\A Palma Engineering\PDI\150522 Busway Seismic Bracing\ Page 1

Customer: PDI, 4200 Oakleys Court, Richmond, VA 23223 Date: 5/31/2017 A. PALMA e n g i n e e r i n g Tag: Seismic Restraint Suspended Bus System Supports Building Code: 2012 IBC/2013 CBC&ASCE7-10 STRUCTURAL CALCULATIONS For Office Use Only: Busrail busway bus system Unistrut - 2013cbc.xmcd C:\Users\TUNG\A Palma Engineering\PDI\150522 Busway Seismic Bracing\ Page 2

Customer: PDI, 4200 Oakleys Court, Richmond, VA 23223 Date: 5/31/2017 A. PALMA e n g i n e e r i n g Tag: Seismic Restraint Suspended Bus System Supports Building Code: 2012 IBC/2013 CBC&ASCE7-10 DESIGN CRITERIA: Govening Code: 2012 International Building Code/2013 California Building Code (CBC) & ASCE7-10 DESCRIPTION: Substantiate suspended electrical bus system seismic load and dead weight. Members will be chosen to design at worst case load combination according to ASCE7 Chapter 2. LOADING CRITERIA: VERTICAL LOAD: L s := 5 ft Maximum tributary length of support for dead load W 250 := 7 lb ft Max. weight for 250Amp bus system W 400 := 10 lb ft Max. weight for 400Amp bus system W 800 := 20 lb ft Max. weight for 800Amp bus system SEISMIC LOAD: Seismic demand per each different project can be determined through this equation: where, z := 1 0.4 a p S DS F p := 1 2 z R + and can be simplify to this, F p h p := 0.50 S DS I p Height in structure of point of attachment of component w/ respect to the base h := 1 Average roof height of structure w/ respect to base I p := 1.0 Component importance factor a p := 2.5 Component amplification factor (ASCE7, table 13.6-1) R p := 6.0 Component response modification factor (ASCE7, table 13.6-1) S DS Spectral acceleration, short period. (Per project's structure sheet or USGS Seismic Design Maps) Let's assume seismic demand cateogorize into these three zone: F p1 := 0.50 Seismic demand at 0.50G F p2 := 0.75 Seismic demand at 0.75G F p3 := 1.00 Seismic demand at 1.00G For Office Use Only: Busrail busway bus system Unistrut - 2013cbc.xmcd C:\Users\TUNG\A Palma Engineering\PDI\150522 Busway Seismic Bracing\ Page 3

Customer: PDI, 4200 Oakleys Court, Richmond, VA 23223 Date: 5/31/2017 A. PALMA e n g i n e e r i n g Tag: Seismic Restraint Suspended Bus System Supports Building Code: 2012 IBC/2013 CBC&ASCE7-10 SEISMIC DESIGN AT 0.50G: converting Horizontal Seismic Force, F ph, in allowable yields F ph := 0.7 F p1 = 0.35 ASCE7 Sect. 13.1.7, for ASD additional Vertical Seismic Force, F pv, yields: F pv := 0.20 CHECK SEISMIC BRACE MEMBER: REACTIONS: θ := 45 deg Allowable brace ratio angle (1:1 = 45.0, 1.5:1 = 56.3, 2:1 = 63.4 ) N brt := 1 Number of brace(s) in transverse direction N brl := 1 Number of brace(s) in longitudinal direction For 250Amp & 400Amp bus system: L t1 := 40 ft Maximum tributary length of support for transverse seismic L l1 := 80 ft Maximum tributary length of support for longitudinal seismic For 800Amp bus system: L t2 := 20 ft Maximum tributary length of support for transverse seismic L l2 := 40 ft Maximum tributary length of support for longitudinal seismic Maximum brace compression in transverse direction ( ) L t1 ( ) L t2 F ph W 400 F ph W 800 F brt1 := = 198lb F N brt cos( θ) brt2 := N brt cos( θ) Maximum brace compression in longitudinal direction ( ) L l1 ( ) L l2 F ph W 400 F ph W 800 F brl1 := = 396lb F N brl cos( θ) brl2 := N brl cos( θ) = 198lb = 396lb COMPRESSION CHECK FOR SINGLE STRUT: Unistrut P1000 Member designation L u2 := 120 in Unbraced length of member P allow := 1380 lb Max. allowable load at slot face F brl2 = 396lb P allow = 1380lb Okay! CHECK STRUT NUT CONNECTION: 3/8" Dia. Strut Nut Member designation V allow := 800 lb Allowable resistance to slip N snut := 1 Number of strut nut(s) F brt2 = 198lb V allow N snut = 800 lb Okay! For Office Use Only: Busrail busway bus system Unistrut - 2013cbc.xmcd C:\Users\TUNG\A Palma Engineering\PDI\150522 Busway Seismic Bracing\ Page 4

Customer: PDI, 4200 Oakleys Court, Richmond, VA 23223 Date: 5/31/2017 A. PALMA e n g i n e e r i n g Tag: Seismic Restraint Suspended Bus System Supports Building Code: 2012 IBC/2013 CBC&ASCE7-10 CHECK HANGER ROD MEMBER: MEMBER PHYSICAL PROPERTIES: d := 0.375 in Min. all-threaded rod member size N hr := 1 Number of hanger supporting busduct CHECK FOR TENSION: T hrallow := 730 lb Allowable load per MSS SP-58 W 800 L s + W 800 L s F pv T rod := + F N brl2 sin( θ) = 400 lb T hrallow = 730lb Okay! hr CHECK FOR COMPRESSION FROM UPLIFT: P rod := W 800 L s + W 800 L s F pv F N brl2 sin( θ) = 160lb hr Using AISC requirements for maximum allowable length and maximum allowable stress: K L hr d 200 where, K := 1.0 d = 0.375 in r r hr := hr 4 200 r hr therefore, L hr := = 18.75 in (Maximum length allowed for K hanger rod subjected to compression without stiffener) Let stiffen hanger rod with 1-5/8"x12GA single channel with rod's clamp at L u3 := 13 in Thus, F e := K L u3 = 139 where, F r y := 36000 lb E := 29000000 lb A := 0.555 in 2 hr in 2 in 2 π 2 E K L u3 r hr 2 = 14885 lb in 2 K L u3 E = 139 > 4.71 = 134 (AISC Sect. 16.1, Chapt. E-3) r hr F y F cr := P n := 0.877 F e F cr A = 13054 lb in 2 = 7245lb CHECK FOR FAILURE: Ω := 1.67 Safety factor P rod = 160lb P n Ω = 4338lb Okay! For Office Use Only: Busrail busway bus system Unistrut - 2013cbc.xmcd C:\Users\TUNG\A Palma Engineering\PDI\150522 Busway Seismic Bracing\ Page 5

Customer: PDI, 4200 Oakleys Court, Richmond, VA 23223 Date: 5/31/2017 A. PALMA e n g i n e e r i n g Tag: Seismic Restraint Suspended Bus System Supports Building Code: 2012 IBC/2013 CBC&ASCE7-10 CHECK SEISMIC ANCHOR ATTACHMENT TO CONCRETE STRUCTURE: Per ASCE 13.4.2, Anchor's design force must carry 2.5 times the force in the component. conc := 2.5 Anchor design factor to concrete lrfd := 0.7 ASD to LRFD ANCHOR REACTION(S) AT SEISMIC BRACE TO STRUCTURAL LOCATION: conc T a := ( F brl2 sin ( θ ) ) = 1000 lb Seismic brace anchor tension lrfd conc V a := ( F brl2 cos ( θ ) ) = 1000 lb Seismic brace anchor shear lrfd Consider Powers Stud SD2 expansion anchor at 1/2" dia. with 3-1/4" min. effective embedment. ANCHOR REACTION(S) AT SEISMIC HANGER TO STRUCTURAL LOCATION: P o := W 800 L s + W 800 L s N hr F pv T a2 := P o + T a = 1120lb Seismic hanger anchor tension Consider Powers Stud SD2 expansion anchor at 1/2" dia. with 3-1/4" min. effective embedment. ** Refer to attached Powers Design Assist for anchor specification and concrete break-out calculations. For Office Use Only: Busrail busway bus system Unistrut - 2013cbc.xmcd C:\Users\TUNG\A Palma Engineering\PDI\150522 Busway Seismic Bracing\ Page 6