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Page 1: BRBF

PROJECT : PAGE :

CLIENT : DESIGN BY :

JOB NO. : DATE : REVIEW BY : Seismic Design for Buckling-Restrained Braced Frames Based on AISC 360-05 & AISC 341-05

DESIGN CRITERIA1. Bracing member self shall be composed of a structural steel core & a system that restrains the steel core from buckling.

The each end of brace to gusset plate may be standard bolted connections, modified bolted connections, or true pinconnections. Selecting bracing members are based on the tested & approved manufacture's lists.

2. The lateral capacity of BRBF, selected bracing members with steel beams and columns, must also be checked by a special

3.

based on geometry and can check the gusset interface weld capacities with moment loads.

INPUT DATA & DESIGN SUMMARY

BRACE CORE AXIAL YIELD STRENGTH 150 kips, SD(from tested & approved manufacture's lists, AISC 341-05, 16.2a)

ANGLE BETWEEN BRACE & COLUMN 25 0

GUSSET DIMENSIONS 24.0 in10.1 in

COLUMN SECTION = > W12X96ORIENTATION = x-x 6.35 in

BEAM SECTION = > W16X67ORIENTATION = x-x 8.15 in

THE CONNECTION DESIGN IS ADEQUATE.( 1" Gusset Plate with 7/16" Fillet Weld, 2 leg x 24" at Column Interface, 2 leg x 11" at Beam Interface. )

ANALYSISDETERMINE REQUIRED STRENGTH OF BRACING CONNECTION (AISC 341-05, 16.3a & 16.2d)

247.1 kips, ASDWhere 1.20 , (AISC 341-05, 16.2d. May be verified by nonlinear time-history or analyses.)

1.44 , (AISC 341-05, 16.2d. May be verified by nonlinear time-history or analyses.)

1.30 , (AISC 341-05, Table I-6-1)

DETERMINE BEST FILLET WELD SIZE PER THICKNESS OF GUSSET & FLANGES (AISC 360-05 J2.2b)

w = 7/16 in0.25 in

0.5625 in [Satisfactory]

DETERMINE REQUIRED THICKNESS OF GUSSET PLATE

1 in 1 in )

DETERMINE CONNECTION INTERFACE FORCES ( AISC Manual 13th Edition, Page 13-10)12.00 in

5.07 in > 3.05 in[the original Uniform Force Method not apply]

-2.55 in0.396054.50812

4.16 in

14.38 in

24.86 in

143.0 kips

63.1 kips

12.5 ft-kips

81.0 kips

41.3 kips

-6.2 ft-kips

CHECK WELD CAPACITY AT INTERFACES (AISC 360-05 J2.4 )

10.37 ksi

4.58 ksi

2.73 ksi

13.90 ksi

7.09 ksi

7.51 ksi2.0

12.68 ksi < 21.00 ksi [Satisfactory]20.16 ksi < 21.00 ksi [Satisfactory]

loads combination of DL + LL + 2 dx/1.5 (AISC 341-05, 16.2b, 16.5b & ASCE 7-05, 12.8.6).

For the connection of gusset plate to beam and column, the interface dimensions of a and b may not satisfy the basic

relationship of the Uniform Force Method: a - b tanq = eb tanq - ec. This software can determine gusset dimensions

Pysc =

q =

2 b =2 a =

, ec =

, eb =

T = (1.1 / 1.5) b w Ry Pysc = b =w =

Ry =

> wMIN =

< wMAX =

tg = ( USE tg =

b =

a = (eb + b) tanq - ec =

K = eb tanq - ec =D = tan2q + (a / b)2 =K' = a ( tanq + a / b) =

aIdeal = (K' tanq + K (a / b)2 ) / D =

bIdeal = (aIdeal - K) / tanq =

r = [(eb + bIdeal)2 + (ec + aIdeal)2] 0.5 =

Vc = (bIdeal / r) T =

Hc = (ec / r) T =

Mc = Hc [ bIdeal - b ] =

Vb = (eb / r) T =

Hb = (aIdeal / r) T =

Mb = Vb [ aIdeal - a ] =

fVc = Vc / (4 b 0.707 w) =

fHc = Hc / (4 b 0.707 w) =

fMc = 3 Mc / (4 b2 0.707 w) =

fVb = VB / (4 a 0.707 w) =

fHb = HB / (4 a 0.707 w) =

fMb = 3 Mb / (4 a2 0.707 w) =W =

fv,c = [(fvc)2 + (fHc+ fMc)2] 0.5 = 0.6 FEXX / W =

fv,b = [(fvb)2 + (fHb + fMb)2] 0.5 = 0.6 FEXX / W =

b

a

b

a

Page 2: BRBF

PROJECT : PAGE :

CLIENT : DESIGN BY : JOB NO. : DATE : REVIEW BY :

Seismic Design for Buckling-Restrained Braced Frames Based on AISC 360-05 & AISC 341-05

INPUT DATA & DESIGN SUMMARYBEAM SECTION = > W16X67 = > A dBEAM DISTRIBUTED SERVICE LOADS D = 0.24 kips / ft 20 16.3 0.40 10.20 0.67 119

L = 0.5 kips / ft kBEAM LENGTH 26 ft 970 6.96 2.44 132 1.37

1 Yes

150 kips,ASD (AISC 341, 16.5b)

25 kips

BEAM YIELD STRESS 50 ksi

THE BEAM DESIGN IS ADEQUATE.

CHECK LOCAL BUCKLING LIMITATION (AISC 341-05 Tab. I-8-1) < = does not apply for top flange continuously braced.

7.67 < N/A [Satisfactory]Where 29000 ksi

34.33 <N/A

N/A

[Satisfactory] Where 2.0 , (AISC 341-05, Table R3-1)

1000 kips

DETERMINE MOMENT ON THE BEAM

225.03 ft-kips, ASD

DETERMINE UNBALANCED SEGMENT LENGTH ABOUT X - AND Y - AXES

26 ft

13 ft

CHECK COMPRESSION CAPACITY (AISC 360-05 E3)

370.76 kips > [Satisfactory]Where 2.0 , (AISC 341-05, Table R3-1)

K = 1.0

63.95 < 200 [Satisfactory]

2.656

69.9786 ksi (AISC 360-05 E3)

37.08 ksi (AISC 360-05 E3)

DETERMINE FLEXURAL DESIGN STRENGTH (AISC-AISC 360-05 F1)

13.00 ft

8.62 ft

26.24 ft

550.0 ft-kips

138.688 ksi

Where 2.80 G J1.00 119 11200 2.62 7300

15.64 in

tw bf tf Sx

Ix rx ry Zx

L =

TOP FLANGE CONTINUOUSLY BRACED ?BEAM AXIAL LOAD AT 2dx/1.5 STORY DRIFT P2dx =

BEAM VERT LOAD AT 2dx/1.5 STORY DRIFT V2dx =

Fy =

bf / (2tf ) = 0.3 (Es / Fy)0.5 =

Es =

h / tw =3.14(Es/Fy)0.5(1-1.54P2DWo/Py) = , for P2DWo/Py < 0.125

1.12(Es/Fy)0.5(2.33-P2DWo/Py) = , for P2DWo/Py > 0.125

Wo =

Py = FyA =

M = (D + L) L2/ 8 + V2dx L/ 4 =

Lx =

Ly =

Pn/Wo = FcrA/Wo = P2dx

Wo =

MAX(KLx/rx, KLy/ry) =

lc = (KL / r) (Fy / E)0.5 =

Fe = p2 E / (KL / r)2 =

Fcr =

Lb =

Lp = 1.76 ry (E / Fyf)0.5 =

Mp = Fy Zx =

rts =[( Iy Cw)0.5/ Sx]0.5 = Iy Cw

c =

h0 = d - tf =

20

0

0.71.95 1 1 6.76

0.7x

y x

FE Jc y S hL rr ts E JcF S h

22

20

1 0.078b b

xb

E JcC LFcrS h rtsL

rts

p

Page 3: BRBF

1.30 , (AISC 360-05 F1)Cb =

Page 4: BRBF

(cont'd)

= N/A

= = 550

= N/A

275 ft-kips

CHECK FLEXURAL CAPACITY (AISC 360-05 C2.1b)

245.71 ft-kips < 275 ft-kips

Where 2852 kips [Satisfactory]1.0 (AISC 360-05 C2.1b)1.6

1.092

CHECK INTERACTION CAPACITY (AISC 360-05 H1.1)

1.20 < 4/3 [Satisfactory]N/A

Mp ft-kips, for Lb @ [0 , Lp]

Mn MIN{Cb [Mp - (Mp - 0.75 Fy Sx) (Lb - Lp) / (Lr - Lp)] , Mp} ft-kips, for Lb @ (Lp , Lr]

MIN(Fcr Sx , Mp) ft-kips, for Lb @ (Lr , Larger)

Mn/Wo =

M = B1M = Mn/Wo =

Pe1 = p2EsIx / (KLx)2 =

Cm =a =

B1 = MAX[ Cm/(1 - a P2D/Pe1) , 1.0] =

For P2D Wo/Pn≥0.2, P2D Wo /Pn + 8 / 9 (M Wo / Mn) =

For P2D Wo/Pn<0.2, P2D Wo / (2Pn) + M Wo / Mn =

Page 5: BRBF

PROJECT : PAGE :

CLIENT : DESIGN BY : JOB NO. : DATE : REVIEW BY :

Seismic Design for Buckling-Restrained Braced Frames Based on AISC 360-05 & AISC 341-05

INPUT DATA & DESIGN SUMMARYCOLUMN SECTION = > W12X96 = > A dCOLUMN AXIAL SERVICE LOADS D = 22 kips 28.2 12.7 0.55 12.20 0.90 131

L = 29 kips k100 kips, ASD (AISC 341, 16.5b) 833 5.43 3.09 147 1.50

UNBRACED COLUMN LENGTH 14 ft

COLUMN YIELD STRESS (36 or 50) 50 ksi THE COLUMN DESIGN IS ADEQUATE.

DETERMINE DESIGN LOAD (AISC 341-05, 16.2b & 16.5b)

151 kips, ASD (Compression, Governs)

CHECK LOCAL BUCKLING LIMITATION (AISC 341-05 Tab. I-8-1)

6.78 < 7.22 [Satisfactory]Where 29000 ksi

17.64 <N/A

57.07

[Satisfactory] Where 2.0 , (AISC 341-05, Table R3-1)

1410 kips

CHECK COMPRESSION CAPACITY (AISC 360-05 E3)

568.31 kips > [Satisfactory]Where 2.0 , (AISC 341-05, Table R3-1)

K = 1.0

54.29 < 200 [Satisfactory]

2.254 (AISC 360-05 E2-4, Pg 6-47)

97.0943 ksi (AISC 360-05 E3)

40.31 ksi (AISC 360-05 E3)

tw bf tf Sx

Ix rx ry Zx

COL AXIAL LOAD AT 2dx/1.5 STORY DRIFT P2dx =L =

Fy =

P = D + L + P2dx =

bf / (2tf ) = 0.3 (Es / Fy)0.5 =

Es =

h / tw =3.14(Es/Fy)0.5(1-1.54PWo/Py) = , for PWo/Py < 0.125

1.12(Es/Fy)0.5(2.33-PWo/Py) = , for PWo/Py > 0.125

Wo =

Py = FyA =

Pn/Wo = FcrA/Wo = P

Wo =

MAX(KLx/rx, KLy/ry) =

lc = (KL / r) (Fy / E)0.5 =

Fe = p2 E / (KL / r)2 =

Fcr =