C4: DESIGN OF COLUMN AS PER IS CODE

 COLUMN DESIGN

DATA:

Dimension                  =   230*230 mm

Axial load on column =   140 KN

Since the column is effectively held in position and restrained against rotation at both ends

                              Le  =  3 m

CHECK FOR MINIMUM ECCENTRICITY:

In the direction of longer span (   e_min) = (le/500) + (D/30)

 = (3/500) + (0.2/30)

 (e_min) = 0.0126 m

In the direction of shorter span    (e_min) = (le/500) + (D/30)

  = (3/500) + (0.2/30)

 (e_min) = 0.0126 m

         In the minimum eccentricity ratio < 0.05

       d’/ D  = 40/250 = 0.2

MAIN REINFORCEMENT:

  Pu/fck*b*d = (140*10³) / (20*200*200)

                      = 0.175

 Mux = Muy = (140*0.012) = 1.68 Kn

               Mu = 1.15 * √(Mux² + Muy²)

                      = 1.15 * √(1.68^2 + 1.68^2)

                Mu = 2.375 KNm

Mu/fck*b*d² = (2.375*10⁶) / (20*200*200²)

                       = 2.9625

Refer chart 46 of sp-16 (fy=415 N/mm² , d’/D=0.2)

                     p/fck = 0.06

 p = (0.06*20) = 1.2

                                                    Asc = (p*b*d) / 100

     = (1.2*200*200) / 100

                                                  Asc = 480 mm²

Provide 6 bars of 12mm dia ( Asc = 678.5mm²)

LATERAL TIES:

Tie diameter ; ϕ_t <{(1/4)*22 = 5.5mm = 6mm

                        Provide 8mm ties

Tie spacing ; s_t > { 200mm

                                 (16*12) = 200mm

                                 (48*8) = 384mm }

Providing spacing 200mm

Provide 8mm dia ties at 200mm spacing.