Short column With axial loading

Note:- Editing can be allow only in yellow cells

Loads

P 120 kN Fck = 25 N/mm2

Fy = 415 N/mm2

Size of column

B = 230 mmD = 230 mm

% of Steel 0.8 %Assumed

Effective length

Ley 2000 mmLez 2500 mm

Ley / B 8.70 short column in Ley Direction

Lez / D 10.86957 short column in Lez Direction

Capacity of column

Pu = 0.4 Fck Area of concrete + 0.67 Fy Area of steel

Pu = 524.77 117.67 kN

Pu = 642.4388 kN

column is safe

Area of Steel = 423.2 mm2

For Dia of Bar = 12 mm

No. of bar required = 4 Nos.

+

Short column With Biaxial moments

Note:- Editing can be allow only in yellow cellsLoads

Pu 1600 kN Fck = 15 N/mm2Muz 120 kN-mMuy 90 kN-m Fy = 415 N/mm2

Size of column

B = 400 mmD = 600 mm

% of Steel 1.2 %Assumed

Effective length of column

Ley 4.26 m

Lez 4.26 m

Ley / B 10.65 column is short in Ley Direction

Lez / D 7.10 column is short in Lez Direction

Minimum Eccentricity

e = (Effective length of column/500 +( B or D) / 30 ) OR 2cm whichever is max

Ex 2.19 cm OR 2 Whichever is maximumEy 2.85 cm OR 2 Whichever is maximum

Moment due to minimum eccentricity

Mz 34.97 kN-m Actual mmt is maxMy 45.63 kN-m Actual mmt is max

Pu 1600 kNMuz 120.0 kN-mMuy 90.0 kN-m

Using Dia of Bar = 25 and Cover 40 mm

D

d' = 52.5

d' / D 0.088 For major Dierection. d' / B 0.131 For minor Dierection.

p/Fck = 0.08

Pu / (Fck x B x D ) 0.44

Referring chart from SP-16 Page no between 112-147

Considering d' / D , p/Fck , Pu / (Fck x B x D )

Mux1 / (Fck x B x D^2 ) = 0.09

Mux1 = 194.4 kN-m

Similarly

Muy1 / (Fck x B^2 x D) = 0.083

Mux1Muy1 = 119.52 kN-m & Muy1

Puz = 0.45 Fck Area of concrete + 0.75 Fy Area of steel

Puz = 2496.96 kN

Pu / Puz = 0.64

Alph = 2

Ratio =Mux Muy

Mux1 Muy1

Ratio = 0.948 Less than 1 hence OK.

)(α

+ )(α

≤ 0

ex

ey

B

D

My

MZ

Ultimatemoment carrying capacity of section