Title My Final year Project Water Civil Engineering Beam (Structure) Air Conditioning 1.4 MB 52
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=159.6N/mm
2

LIMITING MOMENT:

Mu lim = 0.138 fck bd
2

= 0.138 x 25 x 1000 x (560)
2

= 1081KN-m

Mulim >Mu

Hence it is Under reinforced section

MAIN STEEL REINFORCEMENT AND SPACING:

Mu=0.87 fy Ast d[1-(Ast fy/bd fck)]

Astreq=6662.40mm
2

Spacing =110mm

Provide 32dia @110mm c/c

(Ast)pro = (1000 x ast)/spacing

= 7307.63 mm
2

(pt) req= 100 x Ast req bd

1.1>1.2

Hence it is safe

DISTRIBUTION REINFORCEMENT:

Ast min = 0.12 x bd

= (0.12/100) bd

= 720mm
2

Spacing =270mm

Provide 16mm dia @ 270mmc/c

CHECK FOR DEFLECTION:

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fs =0.58 x fy x Ast req/ Ast pro

= (0.58 x 415 x 6717)/7307.6

=221N/mm
2

pst (assumed )=1.2%

M.F=0.95

Depth d= span/(20 x M.F)

= 10600/(20 x 1.2)

=555mm< d (assumed)

Hence it is safe

CHECK FOR SHEAR:

Vuc =(Tc x bd ) x k

fck = 25 KN/mm
2

p st = 100 x Ast pro/ bd

= 0.53%

Tc = 0.61 N/mm
2

Vuc = 0.61 x 1000 x 560 x 0.95

= 324.52 KN

Vuc>Vu

Hence it is safe

BEAM DESIGN

DATA:

fck = 25 N/mm
2

fy = 415 N/mm
2