DESIGN OF COLUMNS WITH BIAXIAL BENDING Design Forces : ( ColumN C6 ) Design loads Axial force = 2100 kN fck = 20 N/mm2 Bending moment ( Mz ) = 6 kN-m fy = 415 N/mm2 Bending moment ( My ) = 5 kN-m Depth ( D ) Width ( b ) Mejor Minor Size of column used = 300 600 xu = 300 680 Cover = 40 k = 1.00 1.133333 g = 8.92 5.864134 o of Layers used along longer side = 3 C1 = 0.361 0.390151 of Layers used along shorter side = 3 Dia of Bar Nos C2 = 0.416 0.448876 Bars at corners 20 6 End Layers ( 3D/7 ) 128.57 Others 20 4 Intermidiate Layers st of 0.002 strain from N.A.= 171.43 ce bet the layers parallel to depth= 110 Asc = 3141.6 ce bet the layers parallel to width= 260 Bending about Mejor Axis : Stress Asi Distance of 1st layer from N.A. = 260 Strain at first layer = 0.003033 354.1 942.48 Distance of 2nd layer from N.A. = 150 Strain in 2nd layer = 0.00175 312.20 1256.64 Distance of third layer from N.A. = 40 Strain in 3rd layer = 0.000467 93.33256 942.48 0 0 0 0 0 0 mate Load carrying capacity ( Pu ) = 2113.8 kN imate moment of Resistance ( Muz ) = 59.8 kN-m Bending about Minor Axis : xu = 680 mm k = 1.133333 ( 3D/7 ) 257.14 mm g = 5.864134 Location of 0.002 strain from N.A.= 422.86 mm C1 = 0.390 C2 = 0.449 Stress Asi Distance of 1st layer from N.A. = 640 Strain at first layer = 0.003027 354.1 942.48 Distance of 2nd layer from N.A. = 380 Strain in 2nd layer = 0.001797 314.00 1256.64 Distance of third layer from N.A. = 120 Strain in 3rd layer = 0.000568 113.51 942.48 0 0 0 0 0 0 mate Load carrying capacity ( Pu ) = 2239.8 kN imate moment of Resistance ( Muy ) = 94.36 kN-m Biaxial Bending with axial force : Puz = 2569.6 kN Pu / Puz = 0.817 Alpha Value Alpha = 2.00 Pu/Puz Alpha 0.2 1 0.8 2 Interaction Check for Biaxial Bending : ( Muz1 / Muz ) Alpha + ( Muy1 / Muy ) Alpha <=1
C6 DESIGNDESIGN OF COLUMNS WITH BIAXIAL BENDINGDesign Forces :(
ColumN C6 ) Design loadsMejorMinor2113.792239.84PuAxial force
=2100kNfck =20N/mm259.894.36MuBending moment ( Mz ) =6kN-mfy
=415N/mm2Bending moment ( My ) =5kN-mInteraction checkDepth ( D
)Width ( b )MejorMinoraxis0.01Size of column used =300600xu
=300680Cover =40k =1.001.1333333333fe 415fe500g =8.925.8641344047No
of Layers used along longer side =3C1
=0.3610.39015110090.00144288.70.00174347.8No of Layers used along
shorter side =3Dia of BarNosC2
=0.4160.44887612690.00146290.50.00185358.7Bars at corners206End
Layers( 3D/7 )
=128.57mm0.00148292.30.00195369.7Others204Intermidiate LayersDist
of 0.002 strain from
N.A.=171.43mm0.0015294.10.00211380.50.00152295.90.00226391.3Distance
bet the layers parallel to depth=110Asc
=3141.60.00154297.70.00252402.2Distance bet the layers parallel to
width=2600.00157300.70.00277413Bending about Mejor Axis
:StressAsiDistance of 1st layer from N.A. =260Strain at first layer
=0.0030333081354.1942.480.0016303.70.00295418.5Distance of 2nd
layer from N.A. =150Strain in 2nd layer
=0.0017499854312.201256.640.00163306.70.00312423.9Distance of third
layer from N.A. =40Strain in 3rd layer
=0.000466662893.332555562942.480.00166308.50.00365429.40000.00169310.30.00417434.80000.00172312.20.00175314Ultimate
Load carrying capacity ( Pu ) =2113.79kN0.0018317.1Ultimate moment
of Resistance ( Muz ) =59.8kN-m0.00182318.40.00184319.7Bending
about Minor Axis :0.00186320.90.00188322.2xu =680mm0.0019323.5k
=1.1333333333( 3D/7 ) =257.14mm0.00192324.8g =5.8641344047Location
of 0.002 strain from N.A.=422.86mm0.00197326.6C1
=0.3900.00202328.4C2 =0.4490.00207330.20.00212332StressAsiDistance
of 1st layer from N.A. =640Strain at first layer
=0.0030270066354.1942.480.00217333.8Distance of 2nd layer from N.A.
=380Strain in 2nd layer
=0.0017972852314.001256.640.00223336.1Distance of third layer from
N.A. =120Strain in 3rd layer
=0.0005675637113.51942.480000000.00235340.1Ultimate Load carrying
capacity ( Pu ) =2239.84kN0.00241342.8Ultimate moment of Resistance
( Muy ) =94.36kN-m0.00244343.60.00247344.3Biaxial Bending with
axial force :0.0025345.10.00253345.8Puz
=2569.55kN0.002563460.00259347.3Pu / Puz =0.817Alpha
Value0.00264348.60.00269349.9Alpha
=2.00Pu/PuzAlpha0.00274351.30.210.00276351.80.820.002893530.00302354.1Interaction
Check for Biaxial Bending :0.00308354.70.00315355.3( Muz1 / Muz )
Alpha + ( Muy1 / Muy ) Alpha
