FIGURE 1: TYPICAL BRB DESIGN PROCESS FLOWCHART FOR EQUIVELENT LATERAL FORCE

METHOD, IBC

EOR Sends

BRB MFR

BRB MFR sends EOR

YES

NO

START

Calc. V using R, Ie & Ta.

Did member

sizes change?

Lay out braces. 30%/70% C/T

brace ratio does not apply

Proceed with design documents. Send

manufacturer final info for

coordination.

Assume brace Stiffness

(K=1.5 AscE/L)

Size beam / column sizes

and brace core areas

Distribute lateral forces

Approximate brace and

connection design

Approximate brace lengths

Calc. brace stiffness/

stiffness factors KF

Calculate brace over-

strength factors ωωωω and βωβωβωβω.

Calc. actual bldg period T

and refine base shear V.

Redistribute lateral forces.

NOTE:

DESIGN ENGINEER PROCESS NOTED IN BLUE,

BRB MANUFACTURER PROCESS NOTED IN TAN.

END

1. Rec. Fy range for core material.

2. Brace stiffnesses/KF factors.

3. Over-strength factors ωωωω / βωβωβωβω.

4. MFR may make design

recommendations.

1. Bay sizes / brace configuration

2. Approx. beam/column sizes

3. Approx. brace cap. / areas.

4. R/Cd, I, ρ ρ ρ ρ, and assumed Fy-min value

and stiffness factor KF.

5. Code forces Pu and bldg drifts.

Confirm project braces do

not exceed tested

assemblies.