DESIGN OF T BEAM

1.0 DETAILSFloor finish = 150 Kg/m2Live load = 1000 Kg/m2M20 concrete and Fe415 steel are used

Depth of slab = 175 mm Span of beam = 6.98 m

Depth of beam, D = 700 mm

Width of beam, b = 300 mm

Spacing of beams = 5.88 m

Clear cover = 45mm 2.0 LOAD ON THE BEAMDead load of slab = 0.175 * 25 = 4.375 KN/m2Total dead load = dead load of slab + floor finish = 4.375 + 1.5 = 5.875 KN/m2Dead load from slab on beam = 5.875 * 5.88 = 34.55 KN/mRibs and finishes = (0.3 * 0.525 * 25) + 5% = 4.137 KN/mTotal deal load on beam = 34.55 + 4.137 = 38.69 KN/m

Total live load = 10 * 5.88 = 58.80 KN/m3.0 DESIGN MOMENTTotal factored load = 1.5 * (38.69 + 58.8) = 146.24 KN/m

Moment at mid-span = 1/12 * 146.24 * 6.982 = 577.5 KN-mMoment at end support = 1/10 * 146.24 * 6.982 = 693 KN-m4.0 CALCULATION OF EFFECTIVE WIDTH AND EFFECTIVE DEPTHThe effective width of the flange is taken as the least value of the following.

(b)

c/c distance of beam = 5.88 m

Therefore the effective flange width (bf) = 2.513 m

Effective depth (d) = 700 (45 + 12.5) = 642.5 mm (25 mm rods and 45 mm cover)5.0 DETERMINATION OF THE NEUTRAL AXIS DEPTH FOR MAXIMUM MOMENT

The neutral axis of the T-beam lies within the flange of the beam.6.0 DETERMINATION OF MAIN STEEL REINFORCEMENTTable 2, SP16 is used to calculate the reinforcement.6.1 At Mid-Span

%of steel, pt = 0.161

Provide 6 - 25 mm rods. (As = 2945.24 mm2 > 2599.51 mm2)6.2 At Supports

%of steel, pt = 0.193

Provide 4 25 mm rods and 4 20 mm rods. (As = 3220.14 mm2 > 3116.18 mm2)7.0 SHEAR REINFORCEMENT

7.1 At Supports

Assuming 8 mm, 2-legged stirrups,

Provide 8 mm , 2-legged stirrups @ 60 mm c/c for a distance of 1.74 m from both the supports.7.2 At Mid-Span

Provide 8 mm , 2-legged stirrups at 300 mm c/c for a length of 3.49 m after a distance of 1.74 m from the supports.