Seismic Brace Axial Forces Calc & Design Cases Summary
Right Brace Section Properties & Member Data
Brace sect HSS6.875X0.500
Grade
= A500 Gr.C Round
Fy
= 46.0
[ksi]
Ratio of expected Fy to specified min Fy
Ry
= 1.30
AISC 341-16 Table A3.1
Ag
= 9.360
[in2]
ry
= 2.272
[in]
E
= 29000
[ksi]
Brace member length & effective length factor K
L
= 144.0
[in]
K
= 1.00
Right Brace Seismic Design Force in Tension
Brace expected yield strength in tension
Pet
= Ry Fy Ag
= 559.7
[kips]
AISC 341-16 F2.6c (1)
Right Brace seismic design force in tension
Ps_t
= Pet
= -559.7
[kips]
AISC 341-16 F2.6c (1)
Right Brace Seismic Design Force in Compression
Member length L & effective length factor K
L
= 144.0
[in]
K
= 1.00
Member radius of gyration & elastic modulus
r
= 2.272
[in]
E
= 29000
[ksi]
Member slenderness ratio
KL/r
= K x L / r
= 63.37
Elastic buckling stress
Fe
= 71.27
[ksi]
AISC 15th Eq E3-4
when
KL/r
≤ 4.71 (
E/Ry Fy
)
0.5 = 103.72
AISC 15th E3
Critical stress
Fcr
= 0.658 ( Ry Fy / Fe ) Ry Fy
= 42.09
[ksi]
AISC 15th Eq E3-2
Brace expected yield strength in compression
Pec
= min ( Ry Fy Ag , 1.14 Fcr Ag )
= 449.1
[kips]
AISC 341-16 F2.3
Brace force in compression
Pc
= from user input in load section
= 0.0
[kips]
Right Brace seismic design force in compression
Ps_ci
= Pec
= 449.1
[kips]
AISC 341-16 F2.6c (2)
Right Brace seismic design force in compression - post-buckling
Ps_cii
= 0.3 x Pec
= 134.7
[kips]
AISC 341-16 F2.3 (ii)
Left Brace Section Properties & Member Data
Brace sect HSS6.875X0.500
Grade
= A500 Gr.C Round
Fy
= 46.0
[ksi]
Ratio of expected Fy to specified min Fy
Ry
= 1.30
AISC 341-16 Table A3.1
Ag
= 9.360
[in2]
ry
= 2.272
[in]
E
= 29000
[ksi]
Brace member length & effective length factor K
L
= 144.0
[in]
K
= 1.00
Left Brace Seismic Design Force in Tension
Brace expected yield strength in tension
Pet
= Ry Fy Ag
= 559.7
[kips]
AISC 341-16 F2.6c (1)
Left Brace seismic design force in tension
Ps_t
= Pet
= -559.7
[kips]
AISC 341-16 F2.6c (1)
Left Brace Seismic Design Force in Compression
Member length L & effective length factor K
L
= 144.0
[in]
K
= 1.00
Member radius of gyration & elastic modulus
r
= 2.272
[in]
E
= 29000
[ksi]
Member slenderness ratio
KL/r
= K x L / r
= 63.37
Elastic buckling stress
Fe
= 71.27
[ksi]
AISC 15th Eq E3-4
when
KL/r
≤ 4.71 (
E/Ry Fy
)
0.5 = 103.72
AISC 15th E3
Critical stress
Fcr
= 0.658 ( Ry Fy / Fe ) Ry Fy
= 42.09
[ksi]
AISC 15th Eq E3-2
Brace expected yield strength in compression
Pec
= min ( Ry Fy Ag , 1.14 Fcr Ag )
= 449.1
[kips]
AISC 341-16 F2.3
Brace force in compression
Pc
= from user input in load section
= 0.0
[kips]
Left Brace seismic design force in compression
Ps_ci
= Pec
= 449.1
[kips]
AISC 341-16 F2.6c (2)
Left Brace seismic design force in compression - post-buckling
Ps_cii
= 0.3 x Pec
= 134.7
[kips]
AISC 341-16 F2.3 (ii)
Brace Axial Force Design Cases Summary
Refer
to AISC 341-16 F2.3(i), LC1 & LC2 are the load cases in which
all braces are assumed to resist forces corresponding to their expected
strength in tension Ps_t or in compression Ps_ci
F2.3(ii), LC3 & LC4 are the load cases in which all braces are assumed to resist forces corresponding to their
expected strength in tension Ps_t and all braces in compression are assumed to resist their expected
compressive post-buckling strength Ps_cii
LC1 Right Brace Ps_t =-559.7 kips (T) Left Brace Ps_ci =449.1 kips (C)
AISC 341-16 F2.3(i)
LC2 Right Brace Ps_ci =449.1 kips (C) Left Brace Ps_t =-559.7 kips (T)
LC3 Right Brace Ps_t =-559.7 kips (T) Left Brace Ps_cii =134.7 kips (C) post-buckling
AISC 341-16 F2.3(ii)
LC4 Right Brace Ps_cii =134.7 kips (C) Left Brace Ps_t =-559.7 kips (T) post-buckling